CHAPTER 3 SHELL AND TUBE HEAT EXCHANGER

20 CHAPTER 3 SHELL AND TUBE HEAT EXCHANGER 3.1 INTRODUCTION A Shell and Tube Heat Exchanger is usually used for higher pressure applications, which consists of a series of tubes, through which one of the fluids runs. The second fluid flows over the tubes to be heated or cooled. The set of tubes is called tube bundle, and may be composed of several types of tubes, differing in shape and design: plain, longitudinally finned, etc. Extensive research work have been done in the past, design and construction of shell and tube heat exchanger by Anantharaman (1997), design of shell and tube heat exchangers when the fouling depends on local temperature and velocity by David Butterworth (2002), changing different parameters to increase shell and tube heat exchanger performance by Lunsford (1998), studies on performance characteristics of variable area heat exchangers by Narayanan (1998), visualization and determination of local heat transfer coefficients in shell and tube heat exchangers, the effect of leakage on pressure drop and local heat transfer by Huadong Li and Volker Kott Ke (1998), determination of convective heat transfer and friction losses in helically enhanced tubes for both Newtonian and non-newtonian fluids by Rozzi and Massini (2007), developing mathematical models for the estimation of hot and cold fluid outlet temperatures as a function of flow rates and inlet temperatures for a shell and tube heat exchanger by Mandavgane (2006). But not much details are available in literature regarding performance analysis with miscible and immiscible systems in the tube side flow. Hence efforts

21 have been made to study the performance of shell and tube heat exchanger with miscible and immiscible systems. In this part of the thesis a shell and tube heat exchanger having dimensions, 150 mm inner shell diameter, 615 mm length and 32 tubes with square pitch was taken for the experimental studies. The experimental studies involved in the determination of outlet temperature of both cold and hot fluid for various flow rates. The Water-Water System, Kerosene-Water System, Toluene-Water System, Acetic acid-water System and Ethylene Glycol- Water System 9%, 10%, 20% and 25% composition on volume basis were used to determine the performance of shell and tube heat exchanger i.e. Overall Heat Transfer Coefficient (U 0 ), Effectiveness (ε), Shell Efficiency (η S ) and Tube Efficiency (η T ). These experimental data were used to develop NN using general regression. Further, these networks were tested with a set of testing data and then the simulated results were compared with the actual results of the testing data. 3.2 EXPERIMENTAL STUDIES The shell and tube heat exchanger under this study is made of mild steel and consists of outside shell diameter of 0.15 m and 32 inner tubes of outer diameter 0.0125 m with square pitch arrangement. Four baffles with 0.1 m baffle spacing are used. The experiments are carried out with 1-1 pass with both parallel and counter flow patterns with cold fluid (miscible and immiscible systems) in shell side and hot fluid (water) in tube side. The centrifugal pump of 0.5HP, water softener, rotameter and storage vessel of 100 liter capacity is installed for carrying out the experiment. The schematic diagram of 1-1 shell and tube heat exchanger is shown in Figure 3.1.

22 Shell outlet Tube outlet Tube inlet Shell inlet Figure 3.1 Schematic Diagram of 1-1 Shell and Tube Heat Exchanger The schematic diagram of the experimental set up of shell and tube heat exchanger with all accessories is shown in Figure 3.2. At the start of the experiment exchanger was washed with water. The stored cold fluid was pressurized to the tube side of the equipment using a centrifugal pump. The flow control was achieved by a Rotameter connected between the pump and the heat exchanger. Before switching on the heater ensure that the tank is filled with water. A control valve controls the flow of hot fluid to the tube. 3 2 4 5 7 1 6 12 8 10 9 6 11 1 Shell and Tube Heat Exchanger, 2 Hot Water Tank, 3 Level Indicator, 4 Drain, 5 Hot Liquid Inlet, 6 Cold Liquid Tank, 7 Hot Liquid Outlet, 8 Cold Liquid Outlet, 9 Rotameter, 10 Pump, 11 Collecting Tank Figure 3.2 Schematic Diagram of Experimental Setup of Shell and Tube Heat Exchanger

23 The overhead tank was first filled with water and the heater was switched on and heated till temperature reaches 90 o C (T 1 ). The inlet of cold fluid was also noted and then the cold fluid valve was opened. The pump was started and the required water flow rate of the cold fluid was fixed using Rotameter. The hot fluid inlet valve was opened till the steady state has been reached. The flow rate of the hot fluid, the outlet temperature of the hot fluid (T 2 ) and cold fluid (t 2 ) was measured. The flow rate of the cold fluid was changed and new steady state reached. The above procedure was repeated for the all set of readings. The experimental set up of 1-1 shell and tube heat exchanger is shown in Figure 3.3. Figure 3.3 Experimental Setup of Shell and Tube Heat Exchanger 3.3 EXPERIMENTAL DATA FOR PARALLEL FLOW The experimental data for parallel flow shell and tube heat exchanger for Water-Water system, Immiscible and Miscible Systems are shown in the Tables 3.1 to 3.5 (The model calculation for 9% Ethylene Glycol Water system is given in Appendix 1).

Table 3.1 Water-Water System Temperature Cold Fluid (Water) Mass Flow Rate Reynolds Number Hot Fluid (Water) Nusselt Number Temperature Mass Flow Reynolds Number Nusselt Number Shell Heat Transfer Coefficient Tube Overall Capacity Rate Ratio No. of Transfer Units Effectiveness Efficiency K kg/s K kg/s W/m 2 K W/m 2 K W/m 2 K % % % t 1 t 2 m c N Re N Nu T 1 T 2 m h N Re N Nu h o h i U o R c NTU ε η S η T 300.1 318.1 0.0331 240.69 13.42 363.1 336.1 0.0568 492.66 5.28 484.60 282.25 143.16 0.580 0.99 49.79 28.57 42.85 300.1 313.1 0.0663 458.15 18.79 363.1 334.1 0.0568 486.45 6.38 674.98 340.69 177.00 0.860 0.71 41.58 20.63 46.03 300.1 312.1 0.0994 680.36 24.01 363.1 332.1 0.0568 480.21 6.24 861.30 333.04 184.75 0.573 0.74 42.61 19.04 49.20 300.1 311.1 0.1326 898.03 25.82 363.1 331.1 0.0569 477.09 6.26 925.24 333.91 187.87 0.430 0.75 43.02 17.46 50.79 300.1 310.1 0.1658 1111.99 29.38 363.1 330.1 0.0569 473.96 6.12 1051.37 326.21 189.37 0.344 0.76 43.20 15.87 52.38 300.1 307.1 0.1999 1293.01 33.22 363.1 329.1 0.0569 470.82 6.17 1184.46 328.82 194.41 0.286 0.78 43.85 11.11 53.96 300.1 303.1 0.2324 1446.71 35.53 363.1 325.1 0.0570 458.30 6.26 1260.38 332.40 197.93 0.245 0.79 44.27 4.76 60.31 Shell Tube 24

Table 3.2 Kerosene-Water (Immiscible) System Temperature Cold Fluid (Kerosene) Hot Fluid (Water) Heat Transfer Coefficient Mass Reynolds Nusselt Mass Reynolds Nusselt Shell Tube Flow Temperature Overall Number Number Flow Number Number Rate Capacity Rate Ratio No. of Transfer Units Effectiveness Efficiency K kg/s K kg/s W/m 2 K W/m 2 K W/m 2 K % % % t 1 t 2 m c N Re N Nu T 1 T 2 m h N Re N Nu h o h i U o R c NTU ε η S η T 9% Kerosene Water System 300.1 333.1 0.0045 41.454 5.477 363.1 343.1 0.0125 115.35 3.25 186.71 174.22 74.88 0.337 4.0437 80.17 52.38 31.74 300.1 333.1 0.0059 55.272 6.26 363.1 339.1 0.0125 112.63 3.148 213.38 168.43 77.34 0.449 3.1324 75.80 52.38 38.09 300.1 332.1 0.0074 68.481 6.91 363.1 336.1 0.0125 110.62 3.171 235.29 169.35 80.30 0.561 2.6014 72.23 50.79 42.85 300.1 330.1 0.0088 80.73 7.59 363.1 334.1 0.0125 109.29 3.186 257.93 169.98 82.97 0.673 2.2393 69.12 47.61 46.03 300.1 323.1 0.0103 88.317 8.095 363.1 327.1 0.0126 104.61 3.106 273.37 165.06 82.98 0.785 1.9179 65.72 36.50 57.14 300.1 321.1 0.0118 99.043 8.477 363.1 326.1 0.0126 103.94 3.114 285.74 165.38 84.19 0.897 1.7021 62.99 33.33 58.73 300.1 319.1 0.0133 109.31 8.865 363.1 325.1 0.0126 103.28 3.122 298.23 165.70 85.34 0.990 1.5486 60.76 30.15 60.31 10% Kerosene Water System 300.1 331.1 0.0037 34.783 5.032 363.1 336.1 0.0169 149.11 3.567 169.77 190.52 75.30 0.210 4.8277 82.84 49.20 42.85 300.1 329.1 0.0052 47.586 5.857 363.1 335.1 0.0169 148.21 3.575 197.26 190.87 80.34 0.293 3.6970 78.71 46.03 44.44 300.1 329.1 0.0067 61.012 6.647 363.1 334.1 0.0169 147.32 3.452 223.91 184.14 82.78 0.375 2.9711 74.81 46.03 46.03 300.1 327.1 0.0082 73.09 7.172 363.1 332.1 0.0169 145.50 3.468 241.09 184.83 85.20 0.458 2.5059 71.47 42.85 49.20 300.1 323.1 0.0090 77.355 7.595 363.1 327.1 0.0169 141.01 3.376 254.32 179.42 85.29 0.503 2.2830 69.54 36.50 57.14 300.1 319.1 0.0105 86.69 8.029 363.1 326.1 0.0169 140.10 3.385 267.82 179.76 86.86 0.585 1.9961 66.62 30.15 58.73 300.1 317.1 0.0119 97.01 8.58 363.1 324.1 0.0170 138.32 3.402 285.66 180.46 88.87 0.668 1.7893 64.14 26.98 61.90 20% Kerosene Water System 300.1 336.1 0.0032 34.763 4.8548 363.1 343.1 0.0194 178.80 3.77 150.51 202.09 73.20 0.151 5.6822 85.03 57.14 31.74 300.1 337.1 0.0057 61.712 6.2 363.1 340.1 0.0194 175.67 3.665 192.39 196.15 80.64 0.266 3.5569 78.05 58.73 36.50 300.1 329.1 0.0065 65.413 6.518 363.1 335.1 0.0194 170.43 3.708 200.89 197.94 82.49 0.302 3.1998 76.18 46.03 44.44 300.1 327.1 0.0082 80.946 7.4995 363.1 331.1 0.0195 166.30 3.6104 230.71 192.30 85.74 0.380 2.6392 72.52 42.85 50.79 300.1 327.1 0.0090 88.656 7.812 363.1 329.1 0.0195 164.21 3.6285 240.33 193.03 87.22 0.416 2.4513 71.05 42.85 53.96 300.1 325.1 0.0106 102.195 8.179 363.1 327.1 0.0195 162.16 3.646 251.17 193.77 88.80 0.489 2.1257 68.00 39.68 57.14 300.1 324.1 0.0115 110.01 8.5234 363.1 327.1 0.0195 162.16 3.646 261.47 193.77 90.05 0.531 1.9842 66.42 38.09 57.14 25% Kerosene Water System 300.1 336.1 0.0042 47.657 5.5566 363.1 338.1 0.0204 182.71 3.813 164.25 203.896 76.62 0.182 4.6894 82.42 57.14 39.68 300.1 335.1 0.0051 57.277 6.0265 363.1 337.1 0.0204 181.59 3.822 177.99 204.26 79.55 0.220 4.0166 80.06 55.55 41.26 300.1 334.1 0.0060 66.741 6.498 363.1 337.1 0.0204 181.59 3.822 191.80 204.26 82.20 0.259 3.5318 77.93 53.96 41.26 300.1 334.1 0.0068 75.252 6.8 363.1 336.1 0.0205 180.49 3.8315 200.72 204.63 83.87 0.292 3.1958 76.16 53.96 42.85 300.1 333.1 0.0077 84.454 7.277 363.1 335.1 0.0205 179.41 3.7079 214.61 197.94 84.71 0.331 2.8509 74.03 52.38 44.44 300.1 331.1 0.0086 92.692 7.63 363.1 333.1 0.0205 177.23 3.726 224.62 198.68 86.40 0.369 2.6038 72.25 49.20 47.61 300.1 329.1 0.0094 99.227 7.987 363.1 332.1 0.0205 176.14 3.735 234.73 199.05 87.95 0.402 2.4324 70.86 46.03 49.20 Shell Tube 25

Table 3.3 Toluene-Water (Immiscible) System Temperature Cold Fluid (Toluene) Hot Fluid (Water) Heat Transfer Coefficient Mass Flow Reynolds Nusselt Temperature Mass Reynolds Nusselt Shell Tube Overall Number Number Flow Number Number Rate Capacity Rate Ratio No. of Transfer Units Effectiveness Efficiency K kg/s K kg/s W/m 2 K W/m 2 K W/m 2 K % % % t 1 t 2 m c N Re N Nu T 1 T 2 m h N Re N Nu h o h i U o R c NTU ε η S η T 9% Toluene Water System 300.1 323.1 0.0044 35.19 5.25 363.1 330.1 0.0150 124.99 3.35 177.31 178.39 76.22 0.282 4.11 80.43 36.50 52.38 300.1 323.1 0.0059 46.93 6.07 363.1 328.1 0.0150 123.33 3.36 205.02 179.08 81.10 0.376 3.28 76.64 36.50 55.55 300.1 322.1 0.0074 58.12 6.76 363.1 327.1 0.0150 122.51 3.37 227.74 179.42 84.52 0.470 2.73 73.22 34.92 57.14 300.1 321.1 0.0089 69.11 7.28 363.1 326.1 0.0150 121.68 3.38 245.00 179.76 86.89 0.564 2.34 70.08 33.33 58.73 300.1 319.1 0.0104 79.14 7.99 363.1 324.1 0.0150 120.03 3.40 268.59 180.46 89.90 0.658 2.07 67.50 30.15 61.90 300.1 315.1 0.0119 87.09 8.45 363.1 320.1 0.0150 116.75 3.29 282.57 174.59 89.53 0.752 1.80 64.39 23.80 68.25 300.1 312.1 0.0135 95.18 8.88 363.1 316.1 0.0150 113.50 3.33 296.10 175.96 91.30 0.846 1.63 62.09 19.04 74.60 10% Toluene Water System 300.1 325.1 0.0038 30.45 4.89 363.1 331.1 0.0156 130.85 3.47 163.98 189.42 75.06 0.228 4.81 82.78 39.68 50.79 300.1 323.1 0.0053 41.66 5.74 363.1 329.1 0.0156 129.14 3.49 192.24 189.19 80.64 0.318 3.70 78.76 36.50 53.96 300.1 322.1 0.0067 52.92 6.42 363.1 327.1 0.0156 127.42 3.51 214.73 189.00 84.52 0.408 3.03 75.19 34.92 57.14 300.1 321.1 0.0082 63.97 6.94 363.1 326.1 0.0156 126.56 3.51 231.81 188.82 87.14 0.497 2.56 71.92 33.33 58.73 300.1 320.1 0.0091 69.62 7.30 363.1 325.1 0.0156 125.70 3.39 243.45 188.79 86.80 0.546 2.32 69.90 31.74 60.31 300.1 317.1 0.0106 78.81 7.88 363.1 323.1 0.0156 123.99 3.40 261.97 188.58 89.25 0.636 2.05 67.21 26.98 63.49 300.1 312.1 0.0121 85.74 8.37 363.1 319.1 0.0156 120.58 3.44 276.54 188.31 91.33 0.726 1.83 64.75 19.04 69.84 20% Toluene Water System 300.1 327.1 0.0033 28.08 4.85 363.1 334.1 0.0169 145.03 3.58 148.92 198.82 72.84 0.173 5.66 84.98 42.85 46.03 300.1 326.1 0.0058 49.00 6.17 363.1 332.1 0.0169 143.17 3.60 189.08 198.42 81.45 0.305 3.59 78.24 41.26 49.20 300.1 326.1 0.0069 55.68 6.49 363.1 331.1 0.0169 142.24 3.60 199.03 198.45 83.32 0.346 3.23 76.40 41.26 50.79 300.1 324.1 0.0084 68.96 7.19 363.1 329.1 0.0169 140.37 3.62 219.96 198.22 86.97 0.437 2.68 72.83 38.09 53.96 300.1 322.1 0.0092 74.22 7.57 363.1 327.1 0.0169 138.50 3.64 231.04 197.82 88.84 0.478 2.49 71.42 34.92 57.14 300.1 319.1 0.0108 84.85 8.14 363.1 324.1 0.0170 135.70 3.53 247.85 197.29 89.52 0.561 2.14 68.19 30.15 61.90 300.1 315.1 0.0118 88.92 8.42 363.1 321.1 0.0170 132.92 3.56 255.32 197.03 90.79 0.610 2.00 66.67 23.80 66.66 25% Toluene Water System 300.1 345.1 0.0043 43.14 5.52 363.1 354.1 0.0184 178.34 3.55 163.53 202.20 76.26 0.201 4.69 82.42 71.42 14.28 300.1 344.1 0.0052 51.89 6.00 363.1 352.1 0.0184 176.47 3.57 177.54 202.26 79.30 0.243 4.02 80.09 69.84 17.46 300.1 342.1 0.0062 60.04 6.50 363.1 351.1 0.0184 175.53 3.58 192.03 201.84 82.13 0.286 3.54 78.00 66.66 19.04 300.1 341.1 0.0070 67.18 6.83 363.1 349.1 0.0184 173.63 3.59 201.62 201.75 83.98 0.322 3.21 76.27 65.07 22.22 300.1 333.1 0.0079 71.35 7.31 363.1 347.1 0.0184 171.72 3.61 214.58 201.63 86.30 0.365 2.91 74.45 52.38 25.39 300.1 328.1 0.0088 76.45 7.74 363.1 338.1 0.0185 162.88 3.55 226.47 201.2 87.13 0.407 2.63 72.47 44.44 39.68 300.1 323.1 0.0097 79.86 8.03 363.1 329.1 0.0185 153.73 3.62 233.85 201.02 89.06 0.443 2.46 72.24 36.50 53.96 Shell Tube 26

Table 3.4 Acetic acid-water (Miscible) System Temperature Cold Fluid ( Acetic Acid) Hot Fluid (Water) Heat Transfer Coefficient Mass Reynolds Nusselt Mass Reynolds Nusselt Shell Tube Flow Temperature Overall Number Number Flow Number Number Rate Capacity Rate Ratio No. of Transfer Units Effectiveness Efficiency K kg/s K kg/s W/m 2 K W/m 2 K W/m 2 K % % % t 1 t 2 m c N Re N Nu T 1 T 2 m h N Re N Nu h o h i U o R c NTU ε η S η T 9% Acetic Acid Water System 300.1 330.1 0.0045 35.42 5.26 363.1 342.1 0.0125 113.03 3.25 179.87 174.52 75.79 0.345 3.99 79.96 47.61 33.33 300.1 328.1 0.0060 46.38 6.13 363.1 339.1 0.0125 111.01 3.27 209.00 175.45 80.77 0.460 3.18 76.13 44.44 38.09 300.1 327.1 0.0076 57.45 6.65 363.1 336.1 0.0125 108.97 3.17 226.50 169.35 81.53 0.575 2.57 72.02 42.85 42.85 300.1 323.1 0.0091 66.49 7.41 363.1 333.1 0.0125 106.91 3.19 251.56 170.29 84.85 0.691 2.23 69.05 36.50 47.61 300.1 321.1 0.0106 76.19 7.80 363.1 332.1 0.0125 106.29 3.20 264.24 170.61 86.35 0.806 1.94 66.05 33.33 49.20 300.1 321.1 0.0121 87.08 8.48 363.1 332.1 0.0125 106.21 3.20 287.22 170.61 88.67 0.921 1.74 63.61 33.33 49.20 300.1 316.1 0.0137 93.64 8.97 363.1 329.1 0.0125 104.14 3.08 302.23 164.43 87.89 0.964 1.59 61.48 25.39 53.96 10% Acetic Acid Water System 300.1 326.1 0.0038 28.84 4.85 363.1 336.1 0.0169 146.88 3.43 163.74 183.46 74.66 0.216 4.65 82.31 41.26 42.85 300.1 325.1 0.0053 39.81 5.03 363.1 334.1 0.0169 145.03 3.45 169.80 184.14 76.03 0.301 3.40 77.28 39.68 46.03 300.1 324.1 0.0069 50.59 6.39 363.1 332.1 0.0169 143.17 3.46 215.59 184.83 84.20 0.386 2.93 74.60 38.09 49.20 300.1 322.1 0.0084 60.62 7.12 363.1 331.1 0.0169 142.24 3.47 239.42 185.18 87.71 0.471 2.50 71.49 34.92 50.79 300.1 321.1 0.0092 65.99 7.48 363.1 329.1 0.0169 140.37 3.35 251.41 178.73 87.38 0.517 2.27 69.46 33.33 53.96 300.1 320.1 0.0108 76.14 7.85 363.1 326.1 0.0169 137.57 3.38 263.45 179.76 89.11 0.602 1.99 66.57 31.74 58.73 300.1 318.1 0.0123 85.34 8.59 363.1 325.1 0.0169 136.63 3.39 287.69 180.11 91.83 0.687 1.79 64.26 28.57 60.31 20% Acetic Acid Water System 300.1 330.1 0.0034 25.46 6.44 363.1 339.1 0.0194 172.08 3.67 200.92 196.50 84.63 0.159 6.21 86.13 47.61 38.09 300.1 327.1 0.0061 43.63 5.99 363.1 337.1 0.0194 169.97 3.69 186.41 197.21 82.10 0.281 3.42 77.39 42.85 41.26 300.1 326.1 0.0069 49.15 6.52 363.1 336.1 0.0194 168.91 3.69 202.87 197.57 85.22 0.319 3.12 75.76 41.26 42.85 300.1 324.1 0.0087 60.87 7.26 363.1 335.1 0.0194 167.85 3.70 225.26 197.94 89.03 0.403 2.59 72.15 38.09 44.44 300.1 322.1 0.0095 65.55 7.48 363.1 334.1 0.0194 166.78 3.71 231.65 198.31 90.10 0.444 2.39 70.53 34.92 46.03 300.1 321.1 0.0112 76.31 8.02 363.1 334.1 0.0194 166.78 3.71 248.36 198.31 92.52 0.518 2.09 67.67 33.33 46.03 300.1 318.1 0.0122 80.87 8.45 363.1 332.1 0.0195 164.64 3.60 260.82 191.94 92.40 0.563 1.92 65.79 28.57 49.20 25% Acetic Acid Water System 300.1 342.1 0.0045 36.92 5.43 363.1 351.1 0.0204 194.01 3.70 163.72 199.44 77.80 0.195 4.44 81.64 66.66 19.04 300.1 341.1 0.0055 44.30 5.95 363.1 348.1 0.0204 190.86 3.73 179.14 200.41 81.31 0.237 3.83 79.31 65.07 23.80 300.1 336.1 0.0065 49.51 6.56 363.1 347.1 0.0204 189.80 3.73 196.88 200.74 84.85 0.278 3.40 77.28 57.14 25.39 300.1 335.1 0.0073 55.30 6.75 363.1 345.1 0.0204 187.67 3.62 202.49 194.46 84.43 0.314 3.00 75.01 55.55 28.57 300.1 332.1 0.0083 60.85 7.16 363.1 342.1 0.0204 184.43 3.64 214.32 195.46 86.67 0.355 2.72 73.12 50.79 33.33 300.1 330.1 0.0093 66.71 7.38 363.1 338.1 0.0204 180.03 3.68 220.54 196.86 88.01 0.396 2.47 71.21 47.61 39.68 300.1 342.1 0.0045 71.40 7.78 363.1 351.1 0.0204 176.68 3.70 163.72 199.44 77.80 0.432 2.32 69.90 44.44 44.44 Shell Tube 27

Table 3.5 Ethylene Glycol-Water (Miscible) System Temperature Cold Fluid (Ethylene Glycol) Hot Fluid (Water) Heat Transfer Coefficient Mass Reynolds Nusselt Mass Reynolds Nusselt Shell Tube Flow Temperature Overall Number Number Flow Number Number Rate Capacity Rate Ratio No. of Transfer Units Effectiveness Efficiency K kg/s K kg/s W/m 2 K W/m 2 K W/m 2 K % % % t 1 t 2 m c N Re N Nu T 1 T 2 m h N Re N Nu h o h i U o R c NTU ε η S η T 9% Ethylene Glycol Water System 300.1 325.1 0.0045 16.50 4.89 363.1 334.1 0.0125 107.59 3.18 168.65 169.98 72.71 0.350 3.77 79.03 39.68 46.03 300.1 324.1 0.0061 21.74 5.55 363.1 332.1 0.0125 106.21 3.20 191.27 170.61 76.78 0.467 2.98 74.91 38.09 49.20 300.1 322.1 0.0076 26.51 6.25 363.1 330.1 0.0125 104.83 3.08 214.84 164.12 78.50 0.584 2.44 70.94 34.92 52.38 300.1 319.1 0.0091 30.55 6.56 363.1 328.1 0.0125 103.44 3.09 224.83 164.75 79.98 0.700 2.07 67.45 30.15 55.55 300.1 317.1 0.0107 34.60 7.07 363.1 326.1 0.0126 102.06 3.11 241.87 165.38 82.23 0.817 1.82 64.61 26.98 58.73 300.1 316.1 0.0122 38.93 7.56 363.1 324.1 0.0126 100.68 3.12 258.15 166.02 84.24 0.934 1.63 62.06 25.39 61.90 300.1 313.1 0.0138 41.69 7.92 363.1 321.1 0.0126 98.613 3.15 269.57 166.99 85.73 0.951 1.55 60.85 20.63 66.66 10% Ethylene Glycol Water System 300.1 325.1 0.0038 15.10 4.54 363.1 349.1 0.0168 158.54 3.46 157.59 186.28 73.90 0.220 4.53 81.94 60.31 22.22 300.1 324.1 0.0054 20.81 5.39 363.1 348.1 0.0168 157.67 3.47 186.79 186.59 79.82 0.306 3.51 77.87 58.73 23.80 300.1 322.1 0.0069 26.42 6.04 363.1 346.1 0.0168 155.92 3.48 208.94 187.20 83.76 0.393 2.87 74.22 57.14 26.98 300.1 319.1 0.0084 31.30 6.52 363.1 344.1 0.0168 154.14 3.37 225.21 180.88 84.57 0.479 2.38 70.43 52.38 30.15 300.1 317.1 0.0093 33.71 6.78 363.1 340.1 0.0169 150.54 3.40 233.74 182.14 86.10 0.526 2.20 68.82 49.20 36.50 300.1 316.1 0.0108 37.25 7.35 363.1 337.1 0.0169 147.80 3.42 251.97 183.13 88.74 0.613 1.95 66.14 41.26 41.26 300.1 313.1 0.0123 42.03 7.59 363.1 334.1 0.0169 145.03 3.45 260.21 184.14 90.04 0.699 1.73 63.46 39.68 46.03 20% Ethylene Glycol Water System 300.1 338.1 0.0035 8.74 4.10 363.1 350.1 0.0193 183.31 3.71 133.24 199.76 70.22 0.165 4.98 83.29 60.31 20.63 300.1 336.1 0.0061 15.07 5.35 363.1 349.1 0.0193 182.32 3.72 173.49 200.08 80.06 0.291 3.22 76.35 57.14 22.22 300.1 335.1 0.0070 16.95 5.61 363.1 347.1 0.0194 180.31 3.73 181.90 200.74 81.94 0.331 2.90 74.41 55.55 25.39 300.1 330.1 0.0088 20.31 6.21 363.1 343.1 0.0194 176.24 3.64 200.53 195.13 84.24 0.417 2.37 70.34 47.61 31.74 300.1 327.1 0.0097 21.55 6.54 363.1 341.1 0.0194 174.17 3.65 210.43 195.81 86.11 0.456 2.21 68.88 42.85 34.92 300.1 326.1 0.0114 25.01 7.07 363.1 337.1 0.0194 169.97 3.69 227.35 197.21 89.17 0.535 1.95 66.13 41.26 41.26 300.1 323.1 0.0123 26.17 7.42 363.1 334.1 0.0194 166.78 3.71 237.99 198.31 91.05 0.581 1.83 64.72 36.50 46.03 25% Ethylene Glycol Water System 300.1 345.1 0.0046 10.79 4.71 363.1 355.1 0.0203 198.15 3.80 148.54 205.05 75.14 0.204 4.11 80.43 71.42 12.69 300.1 344.1 0.0056 12.88 4.98 363.1 354.1 0.0203 197.12 3.81 157.08 205.36 77.32 0.247 3.49 77.72 69.84 14.28 300.1 343.1 0.0066 14.92 5.51 363.1 352.1 0.0203 195.05 3.70 173.53 199.13 79.88 0.291 3.06 75.42 68.25 17.46 300.1 342.1 0.0074 16.60 5.79 363.1 349.1 0.0204 191.92 3.72 182.17 200.08 81.86 0.328 2.78 73.60 66.66 22.22 300.1 340.1 0.0084 18.32 6.09 363.1 347.1 0.0204 189.80 3.73 191.52 200.74 83.84 0.371 2.52 71.61 63.49 25.39 300.1 339.1 0.0094 20.22 6.37 363.1 344.1 0.0204 186.59 3.76 200.19 201.75 85.69 0.414 2.30 69.77 61.90 30.15 300.1 338.1 0.0103 21.78 6.66 363.1 342.1 0.0204 184.43 3.64 208.88 195.46 85.76 0.451 2.12 67.95 60.31 33.33 Shell Tube 28

29 3.4 EXPERIMENTAL DATA FOR COUNTER CURRENT FLOW The experimental data for counter current flow shell and tube heat exchanger for Water-Water system, Immiscible and Miscible Systems are shown in the Tables 3.6 to 3.10. 3.5 RESULTS AND DISCUSSION In this part of the thesis, the performance characteristics of shell and tube heat exchanger for parallel flow and counter current flow i.e. Overall Heat Transfer Coefficient in terms of Nusselt number for cold and hot fluid, Effectiveness, Efficiency for cold fluid side and hot fluid side related with respect to Reynolds number of the cold fluid are illustrated from Figures 3.4 to 3.53. 3.5.1 Effect of Flow Rate of the Cold Fluid In the Figures 3.4 to 3.8 and Figures 3.24 to 3.28, Nusslet number (Cold) versus Reynolds number (Cold) are plotted which shows that heat transfer coefficients increases with increase in the mass flow rate of cold fliud. This is because increase in flowrate of cold fluid increases the Reynolds number and Nusselt number which inturn increases the individual heat transfer coefficients for hot fluid. The increase in these heat transfer coefficients will increase the overall heat transfer coefficient. In the Figures 3.9 to 3.13 and Figures 3.34 to 3.38, Nusselt number of the hot fluid versus Reynolds number of the cold fluid are plotted, which shows that the Nusselt number of the hot fluid decreases diminutively with the increase in Reynolds number of the cold fluid except for miscible liquids in counter current flow pattern.

Table 3.6 Water-Water System Temperature Cold Fluid (Water) Mass Flow Rate Reynolds Number Nusselt Number Hot Fluid (Water) Temperature Mass Flow Reynolds Number Nusselt Number Shell Heat Transfer Coefficient Tube Overall Capacity Rate Ratio No. of Transfer Units Effectiveness Efficiency K kg/s K kg/s W/m 2 K W/m 2 K W/m 2 K % % % t 1 t 2 m c N Re N Nu T 1 T 2 m h N Re N Nu h o h i U o R c NTU ε η S η T 300.1 323.1 0.0330 240.47 13.50 363.1 329.1 0.0569 493.71 5.23 487.83 285.08 153.85 0.580 0.66 40.06 36.51 53.97 300.1 318.1 0.0662 457.76 18.49 363.1 327.1 0.0569 487.48 5.27 664.07 281.52 166.37 0.859 0.67 40.13 28.67 57.14 300.1 313.1 0.0994 680.25 22.20 363.1 326.1 0.0569 481.08 5.28 796.38 281.89 173.77 0.574 0.69 41.09 20.64 58.73 300.1 312.1 0.1326 897.88 26.03 363.1 323.1 0.0570 478.23 5.28 932.70 281.67 179.39 0.431 0.72 41.85 19.05 63.49 300.1 310.1 0.1658 1111.20 29.34 363.1 321.1 0.0570 475.22 5.28 1049.95 281.29 183.12 0.345 0.73 42.34 15.87 66.67 300.1 309.1 0.1990 1292.60 33.03 363.1 320.1 0.0570 472.07 5.28 1177.83 281.02 186.51 0.288 0.74 42.79 14.29 68.25 300.1 308.1 0.2322 1445.62 34.98 363.1 318.1 0.0571 459.23 5.28 1241.09 280.64 187.82 0.247 0.75 42.96 12.70 71.43 Shell Tube 30

Table 3.7 Kerosene-Water (Immiscible) System Temperature Cold Fluid (Kerosene) Hot fluid (Water) Heat transfer coefficient Mass Mass Reynolds Nusselt Reynolds Nusselt Shell Tube Flow Temperature Flow Overall Number Number Number Number rate rate Capacity Rate Ratio No. of Transfer Units Effectiveness Efficiency K kg/s K kg/s W/m 2 K W/m 2 K W/m 2 K % % % t 1 t 2 m c N Re N Nu T 1 T 2 m h N Re N Nu h o h i U o R c NTU ε η S η T 9% Kerosene Water System 300.1 329.1 0.00444 38.92 5.36 363.1 352.1 0.01250 118.77 3.193 182.09 171.89 78.09 0.338 4.21 82.24 46.0 17.5 300.1 327.1 0.00593 51.13 6.02 363.1 350.1 0.01251 117.12 3.196 204.37 171.93 81.93 0.451 3.31 76.83 42.9 20.6 300.1 325.1 0.00741 62.48 6.71 363.1 347.1 0.01252 115.54 3.198 227.29 171.75 85.33 0.563 2.76 73.41 39.7 25.4 300.1 323.1 0.00890 73.38 7.40 363.1 340.1 0.01255 111.07 3.211 250.20 171.88 88.41 0.675 2.38 70.44 36.5 36.5 300.1 321.1 0.01039 83.77 7.79 363.1 339.1 0.01256 109.52 3.212 262.63 171.85 89.90 0.788 2.07 67.5 33.3 38.1 300.1 320.1 0.01187 94.90 8.47 363.1 338.1 0.01256 108.18 3.212 285.51 171.65 93.37 0.9 1.88 65.36 31.8 39.7 300.1 319.1 0.01336 105.4 8.83 363.1 334.1 0.01257 104.45 3.212 297.18 171.35 93.45 0.987 1.67 62.66 30.2 46.0 10% Kerosene Water System 300.1 320.1 0.00377 30.24 4.88 363.1 335.1 0.01694 145.77 3.548 163.02 189.42 78.25 0.211 5.00 83.36 31.8 44.4 300.1 319.1 0.00525 41.83 5.71 363.1 333.1 0.01695 144.00 3.548 190.64 189.20 84.04 0.294 3.86 79.43 30.2 47.6 300.1 318.1 0.00676 53.26 6.38 363.1 331.1 0.01697 143.91 3.548 212.62 189.00 88.00 0.376 3.15 75.92 28.6 50.8 300.1 316.1 0.00822 63.23 6.94 363.1 330.1 0.01697 142.15 3.547 230.79 188.83 90.91 0.459 2.66 72.75 25.4 52.4 300.1 315.1 0.00903 68.53 7.30 363.1 329.1 0.01698 142.19 3.548 242.73 188.80 92.70 0.504 2.47 71.25 23.8 54.0 300.1 314.1 0.01051 78.74 7.66 363.1 327.1 0.01699 138.63 3.548 254.47 188.58 94.30 0.587 2.16 68.4 22.2 57.1 300.1 312.1 0.01200 85.83 8.14 363.1 326.1 0.01699 135.43 3.548 277.61 188.31 97.21 0.671 1.95 66.1 19.1 58.7 20% Kerosene Water System 300.1 332.1 0.00327 32.83 4.88 363.1 343.1 0.01944 171.85 3.709 150.98 198.83 77.16 0.152 6.00 85.71 50.8 31.8 300.1 330.1 0.00576 56.49 6.14 363.1 337.1 0.01947 169.81 3.713 189.46 198.43 86.01 0.266 3.80 79.17 47.6 41.3 300.1 328.1 0.00655 63.27 6.50 363.1 335.1 0.01949 167.62 3.717 200.17 198.45 88.15 0.303 3.40 77.27 44.4 44.4 300.1 325.1 0.00826 77.31 6.88 363.1 333.1 0.01950 165.49 3.717 211.34 198.22 90.20 0.381 2.80 73.68 39.7 47.6 300.1 323.1 0.00905 82.89 7.56 363.1 330.1 0.01952 163.46 3.716 231.91 197.83 93.63 0.417 2.60 72.22 36.5 52.4 300.1 322.1 0.01063 96.99 8.23 363.1 326.1 0.01954 157.45 3.714 252.16 197.30 96.61 0.489 2.30 69.7 34.9 58.7 300.1 318.1 0.01156 100.6 8.66 363.1 322.1 0.01956 155.66 3.718 264.23 197.04 98.25 0.531 2.20 68.75 28.9 65.1 25% Kerosene Water System 300.1 332.1 0.00426 46.80 5.51 363.1 346.1 0.02044 183.27 3.766 162.62 202.21 80.77 0.183 4.94 83.17 50.8 27.0 300.1 330.1 0.00517 55.46 6.01 363.1 342.1 0.02047 180.95 3.775 176.92 202.26 84.15 0.221 4.24 80.94 47.6 33.3 300.1 329.1 0.00608 64.64 6.33 363.1 337.1 0.02050 178.75 3.776 186.26 201.84 86.12 0.259 3.69 78.72 46.0 41.3 300.1 327.1 0.00686 71.90 6.97 363.1 334.1 0.02052 176.50 3.781 204.69 201.76 89.84 0.293 3.42 77.38 42.9 46.0 300.1 323.1 0.00777 77.82 7.23 363.1 333.1 0.02052 174.20 3.781 211.46 201.64 91.09 0.331 3.06 75.39 36.5 47.6 300.1 320.1 0.00869 83.86 7.47 363.1 330.1 0.02054 172.07 3.780 217.95 201.24 92.17 0.369 2.77 73.52 31.8 52.4 300.1 316.1 0.00947 87.83 7.91 363.1 328.1 0.02055 169.93 3.780 229.77 201.02 94.16 0.403 2.60 72.24 25.4 55.6 Shell Tube 31

Table 3.8 Toluene-Water (Immiscible) System Temperature Cold Fluid (Toluene) Hot Fluid (Water) Heat Transfer Coefficient Mass Mass Reynolds Nusselt Reynolds Nusselt Shell Tube Flow Temperature Flow Overall Number Number Number Number rate rate Capacity Rate Ratio No. of Transfer Units Effectiveness Efficiency K kg/s K kg/s W/m 2 K W/m 2 K W/m 2 K % % % t 1 t 2 m c N Re N Nu T 1 T 2 m h N Re N Nu h o h i U o R c NTU ε η S η T 9% Toluene Water System 300.1 325.1 0.0044 35.11 5.36 363.1 336.1 0.0149 124.76 3.43 180.90 182.71 80.55 0.283 4.34 81.29 39.68 42.86 300.1 323.1 0.0059 46.86 5.88 363.1 332.1 0.0151 123.18 3.41 198.31 181.63 83.54 0.377 3.37 77.16 36.51 49.21 300.1 322.1 0.0074 58.07 6.90 363.1 329.1 0.0150 122.44 3.40 232.63 181.23 88.96 0.471 2.87 74.21 34.92 53.97 300.1 320.1 0.0089 69.06 7.26 363.1 328.1 0.0150 121.61 3.40 244.61 181.05 90.60 0.565 2.44 70.94 31.75 55.56 300.1 318.1 0.0104 79.15 7.64 363.1 327.1 0.0150 119.93 3.41 256.66 181.02 92.19 0.659 2.12 68.04 28.57 57.14 300.1 317.1 0.0119 86.46 8.39 363.1 325.1 0.0150 116.58 3.41 280.52 180.60 94.96 0.753 1.91 65.75 26.98 60.32 300.1 314.1 0.0134 95.08 8.83 363.1 323.1 0.0150 113.27 3.42 294.55 180.62 96.52 0.848 1.73 63.40 22.22 63.49 10% Toluene Water System 300.1 323.1 0.0038 30.43 4.89 363.1 337.1 0.0155 130.61 3.45 163.99 184.19 77.34 0.211 5.00 83.36 31.75 44.44 300.1 320.1 0.0053 41.66 5.76 363.1 336.1 0.0155 128.86 3.46 192.85 184.20 83.21 0.294 3.86 79.43 30.16 47.62 300.1 319.1 0.0068 52.95 6.28 363.1 334.1 0.0155 127.15 3.46 209.90 184.10 86.21 0.376 3.15 75.92 28.57 50.79 300.1 316.1 0.0083 64.03 7.01 363.1 331.1 0.0156 126.37 3.46 234.02 183.81 89.49 0.459 2.66 72.75 25.4 52.38 300.1 314.1 0.0091 69.69 7.24 363.1 328.1 0.0156 125.59 3.45 241.44 183.44 90.90 0.504 2.47 71.25 23.81 53.97 300.1 313.1 0.0106 78.86 7.78 363.1 327.1 0.0156 123.84 3.45 258.55 183.41 93.21 0.587 2.16 68.40 22.22 57.14 300.1 312.1 0.0121 85.72 8.17 363.1 325.1 0.0156 120.37 3.46 269.97 183.20 94.58 0.671 1.95 66.10 19.05 58.73 20% Toluene Water System 300.1 332.1 0.0032 27.46 4.92 363.1 343.1 0.0194 166.31 3.72 150.98 198.82 77.16 0.152 6.00 85.71 50.79 31.75 300.1 330.1 0.0057 47.94 6.18 363.1 337.1 0.0194 164.39 3.72 189.46 198.42 86.00 0.266 3.80 79.17 47.62 41.27 300.1 328.1 0.0065 54.52 6.53 363.1 335.1 0.0194 163.37 3.72 200.17 198.45 88.15 0.303 3.40 77.27 44.44 44.44 300.1 325.1 0.0082 67.54 6.91 363.1 333.1 0.0194 161.23 3.72 211.34 198.22 90.19 0.381 2.80 73.68 39.68 47.62 300.1 323.1 0.0090 72.68 7.59 363.1 330.1 0.0195 159.13 3.72 231.91 197.82 93.63 0.417 2.60 72.22 36.51 52.38 300.1 322.1 0.0106 83.07 8.28 363.1 326.1 0.0195 155.96 3.71 252.16 197.29 96.61 0.489 2.30 69.70 34.92 58.73 300.1 318.1 0.0115 87.06 8.71 363.1 322.1 0.0195 152.81 3.72 264.23 197.03 98.25 0.531 2.20 68.75 28.86 65.08 25% Toluene Water System 300.1 332.1 0.0042 42.16 5.49 363.1 346.1 0.0204 197.63 3.75 162.62 202.20 80.76 0.183 4.94 83.17 50.79 26.98 300.1 330.1 0.0051 50.76 5.98 363.1 342.1 0.0204 195.69 3.75 176.92 202.26 84.15 0.221 4.24 80.94 47.62 33.33 300.1 329.1 0.0060 58.75 6.30 363.1 337.1 0.0204 194.88 3.75 186.26 201.84 86.11 0.259 3.69 78.72 46.03 41.27 300.1 327.1 0.0068 65.75 6.93 363.1 334.1 0.0207 192.83 3.75 204.69 201.75 89.83 0.293 3.42 77.38 42.86 46.03 300.1 323.1 0.0077 69.71 7.20 363.1 333.1 0.0205 190.64 3.75 211.46 201.63 91.08 0.331 3.06 75.39 36.51 47.62 300.1 320.1 0.0086 74.71 7.45 363.1 330.1 0.0205 180.47 3.76 217.95 201.24 92.16 0.369 2.77 73.52 31.75 52.38 300.1 316.1 0.0094 77.95 7.89 363.1 328.1 0.0205 169.97 3.77 229.76 201.02 94.15 0.403 2.60 72.24 25.40 55.56 Shell Tube 32

Table 3.9 Acetic acid-water (Miscible) System Temperature Cold Fluid (Acetic Acid ) Hot Fluid (Water) Heat Transfer Coefficient Mass Mass Reynolds Nusselt Reynolds Nusselt Shell Tube Flow Temperature Flow Overall Number Number number Number rate Rate Capacity Rate Ratio No. of Transfer Units Effectiveness Efficiency K kg/s K kg/s W/m 2 K W/m 2 K W/m 2 K % % % t 1 t 2 m c N Re N Nu T 1 T 2 m h N Re N Nu h o h i U o R c NTU ε η S η T 9%Acetic Acid Water System 300.1 318.1 0.0333 259.42 6.50 363.1 344.1 0.0271 244.21 8.59 222.07 460.25 126.16 0.862 1.05 53.00 28.57 30.15 300.1 315.1 0.0501 382.42 6.50 363.1 343.1 0.0271 239.63 10.82 221.99 578.96 133.68 0.574 1.12 58.50 23.80 31.74 300.1 313.1 0.0669 505.64 6.52 363.1 342.1 0.0271 235.08 13.74 221.96 734.42 140.64 0.430 1.17 63.00 20.63 33.33 300.1 312.1 0.0836 609.36 6.52 363.1 310.6 0.0271 230.50 14.37 221.87 766.64 141.64 0.344 1.20 66.00 19.04 35.38 300.1 311.1 0.1004 717.99 6.54 363.1 339.1 0.0271 229.11 15.89 221.76 847.22 144.09 0.287 1.22 65.30 17.46 38.09 300.1 309.1 0.1172 838.62 6.54 363.1 338.1 0.0271 229.11 17.26 221.67 920.64 146.19 0.245 1.22 67.50 14.28 39.68 300.1 307.1 0.1340 914.94 6.55 363.1 337.1 0.0271 224.51 17.89 221.58 952.57 146.84 0.215 1.23 68.20 11.11 41.26 10%Acetic Acid Water System 300.1 317.1 0.0334 249.49 16.45 363.1 346.1 0.0312 271.16 8.09 233.11 432.25 127.87 0.940 0.98 50.80 26.98 26.98 300.1 314.1 0.0502 371.22 16.50 363.1 344.1 0.0312 267.74 10.10 233.01 539.38 135.86 0.708 0.98 53.00 22.22 30.15 300.1 312.1 0.0671 490.91 16.54 363.1 343.1 0.0313 264.23 11.59 232.92 618.15 140.84 0.530 1.02 56.00 19.04 31.74 300.1 310.6 0.0839 602.76 16.58 363.1 342.1 0.0313 262.52 13.67 232.85 728.60 145.34 0.425 1.05 61.00 16.66 33.33 300.1 309.6 0.1008 717.29 16.07 363.1 341.1 0.0313 259.00 15.00 232.80 798.44 147.92 0.354 1.07 63.00 15.07 34.92 300.1 308.6 0.1176 829.27 16.36 363.1 340.1 0.0313 253.68 15.95 232.70 847.46 149.47 0.303 1.08 64.00 13.49 36.50 300.1 308.1 0.1345 931.27 16.12 363.1 339.6 0.0313 251.89 16.65 232.69 884.30 150.60 0.265 1.09 66.00 12.69 37.30 20%Acetic Acid Water System 300.1 317.1 0.0335 246.77 15.50 363.1 343.1 0.0142 125.56 7.57 178.95 405.09 104.38 0.520 1.66 73.00 26.98 31.74 300.1 315.1 0.0504 360.38 15.56 363.1 342.1 0.0142 123.94 9.14 178.90 488.95 109.17 0.346 1.74 78.00 23.80 33.33 300.1 312.1 0.0673 476.81 15.59 363.1 340.1 0.0142 123.22 10.41 178.78 556.57 112.10 0.260 1.79 80.00 19.04 36.50 300.1 310.1 0.0841 585.90 15.67 363.1 338.1 0.0142 122.49 13.31 178.66 710.83 117.23 0.207 1.87 81.50 15.87 39.68 300.1 308.1 0.1011 691.61 15.40 363.1 335.1 0.0142 121.76 14.41 178.52 769.05 118.62 0.173 1.89 82.30 12.69 44.44 300.1 307.1 0.1180 800.32 15.50 363.1 333.1 0.0142 121.85 15.10 178.38 806.16 119.33 0.148 1.90 83.10 11.11 47.61 300.1 305.6 0.1349 891.74 15.52 363.1 331.1 0.0142 120.30 15.89 178.28 847.56 120.19 0.129 1.91 83.50 08.73 50.79 25%Acetic Acid Water System 300.1 319.1 0.0336 271.98 15.51 363.1 340.1 0.0187 178.07 6.87 196.01 369.80 108.57 0.742 1.32 63.00 30.15 36.50 300.1 315.1 0.0505 404.36 15.51 363.1 338.1 0.0187 175.11 8.52 195.92 457.85 115.07 0.494 1.40 67.00 23.80 39.68 300.1 311.1 0.0674 512.97 15.49 363.1 335.1 0.0187 174.27 9.64 195.69 517.93 118.48 0.370 1.44 69.00 17.46 44.44 300.1 309.1 0.0844 635.20 15.61 363.1 334.1 0.0187 172.20 10.74 195.66 576.45 121.21 0.296 1.47 73.00 14.28 46.03 300.1 307.1 0.1013 740.62 15.63 363.1 333.1 0.0187 169.15 12.37 195.63 662.85 124.68 0.247 1.51 77.00 11.11 47.61 300.1 306.1 0.1184 849.10 15.35 363.1 330.1 0.0104 91.81 13.46 195.42 720.21 126.42 0.212 1.53 74.00 09.52 52.38 300.1 305.6 0.1353 952.81 12.94 363.1 329.1 0.0187 161.86 14.13 195.33 754.74 127.38 0.185 1.54 76.00 08.73 53.96 Shell Tube 33

Table 3.10 Ethylene Glycol-Water (Miscible) System Cold Fluid ( Ethylene Glycol) Hot Fluid (Water) Heat Transfer Coefficient Mass Reynolds Nusselt Mass Reynolds Nusselt Shell Tube Flow Temperature Overall Number Number Flow Number Number Rate Temperature Capacity Rate Ratio No. of Transfer Units Effectiveness Efficiency K kg/sec K kg/sec W/m 2 K W/m 2 K W/m 2 K % % % t 1 t 2 m c N Re N Nu T 1 T 2 m h N Re N Nu h o h i U o R c NTU ε η S η T 9% Ethylene Glycol Water System 300.1 320.1 0.0166 59.63 16.45 363.1 334.1 0.0129 110.38 3.94 567.24 210.31 114.82 0.813 2.03 67.04 31.74 46.03 300.1 317.1 0.0249 88.40 16.50 363.1 333.1 0.0129 108.90 4.50 568.07 240.18 126.80 0.542 2.24 69.19 26.98 47.61 300.1 315.1 0.0332 114.94 16.54 363.1 332.1 0.0129 107.41 4.95 568.39 263.90 135.75 0.406 2.40 70.63 23.80 49.20 300.1 313.1 0.0416 138.20 16.58 363.1 333.1 0.0129 105.93 5.33 568.07 283.62 142.81 0.324 2.53 71.67 20.63 47.61 300.1 311.6 0.0499 160.87 16.07 363.1 329.1 0.0129 104.45 5.66 549.35 300.83 147.44 0.270 2.61 72.32 18.25 53.96 300.1 310.1 0.0582 184.70 16.36 363.1 331.1 0.0129 102.97 5.95 558.80 316.21 153.20 0.231 2.71 73.08 15.87 50.79 300.1 309.1 0.0666 201.08 16.12 363.1 330.1 0.0129 100.77 6.23 548.59 330.36 156.92 0.202 2.78 73.55 14.28 52.38 10% Ethylene Glycol Water System 300.1 318.1 0.0166 64.44 15.50 363.1 339.1 0.0122 114.66 3.86 537.10 207.69 112.47 0.803 2.10 67.80 28.57 38.09 300.1 315.1 0.0250 96.03 15.56 363.1 337.1 0.0122 114.00 4.40 538.70 236.50 123.88 0.533 2.31 69.87 23.80 41.26 300.1 313.1 0.0334 126.98 15.59 363.1 336.1 0.0122 112.66 4.83 539.51 259.62 132.50 0.399 2.48 71.27 20.63 42.85 300.1 311.6 0.0418 154.21 15.67 363.1 335.1 0.0122 111.30 5.20 540.89 278.98 139.43 0.319 2.61 72.31 18.25 44.44 300.1 310.6 0.0501 181.17 15.40 363.1 334.1 0.0122 108.56 5.52 530.39 295.75 144.37 0.266 2.70 73.00 16.66 46.03 300.1 309.6 0.0585 200.62 15.50 363.1 334.1 0.0122 106.49 5.81 531.60 310.99 149.42 0.228 2.79 73.67 15.07 46.03 300.1 309.1 0.0669 226.79 15.52 363.1 333.1 0.0122 104.39 6.07 531.60 324.42 153.66 0.199 2.87 74.21 39.68 46.03 20% Ethylene Glycol Water System 300.1 317.1 0.0168 41.88 15.51 363.1 330.1 0.0095 89.80 3.71 503.57 199.92 107.82 0.646 2.59 72.18 26.98 52.38 300.1 314.1 0.0252 61.47 15.51 363.1 331.1 0.0095 89.29 4.24 502.87 228.25 118.81 0.431 2.85 74.08 22.22 50.79 300.1 312.1 0.0336 81.10 15.49 363.1 332.1 0.0095 88.25 4.80 501.78 25.83 127.00 0.323 3.05 75.34 19.04 49.20 300.1 310.1 0.0420 96.31 15.61 363.1 330.1 0.0095 86.14 5.03 503.57 269.82 133.73 0.259 3.21 76.29 15.87 52.38 300.1 308.1 0.0504 111.85 15.63 363.1 331.1 0.0095 85.07 5.34 502.87 286.31 139.19 0.215 3.34 77.00 12.69 50.79 300.1 307.1 0.0588 128.98 15.35 363.1 329.1 0.0068 59.35 5.63 493.24 301.25 143.20 0.132 4.81 82.80 11.11 53.96 300.1 305.1 0.0673 142.12 12.94 363.1 327.1 0.0068 58.18 5.89 414.66 314.43 139.39 0.115 4.68 82.41 7.93 57.14 25% Ethylene Glycol Water System 300.1 325.1 0.0168 39.01 14.39 363.1 333.1 0.0081 78.76 3.63 453.79 195.59 103.67 0.577 2.92 74.52 39.68 47.61 300.1 321.1 0.0253 57.85 14.43 363.1 331.1 0.0081 78.32 4.14 454.71 223.40 114.17 0.383 3.22 76.31 33.33 50.79 300.1 317.1 0.0337 75.93 14.54 363.1 328.1 0.0081 77.45 4.56 457.79 245.39 122.13 0.288 3.44 77.51 26.98 55.55 300.1 315.1 0.0421 93.54 14.58 363.1 327.1 0.0081 76.13 4.91 458.83 264.01 128.46 0.231 3.62 78.38 23.80 57.14 300.1 313.1 0.0506 109.55 14.64 363.1 326.1 0.0081 75.24 5.21 459.86 280.23 133.77 0.192 3.77 79.06 20.63 58.73 300.1 312.1 0.0591 126.42 12.15 363.1 323.1 0.0054 49.26 5.49 381.30 294.77 130.22 0.109 5.51 84.65 19.04 63.49 300.1 311.6 0.0675 142.73 12.19 363.1 322.1 0.0054 48.66 5.76 382.41 308.88 133.89 0.096 5.67 85.01 18.25 65.07 Shell Tube 34

35 The graphs plotted aganist Efficiency and Effectiveness versus flow rate of the cold fluid implies that increase in the flow rate decreases the shell side efficiency and increases the tube side efficiency of the heat exchanger which are illustrated from Figures 3.19 to 3.23 and Figures 3.14 to 3.18 respectively. The efficiency of shell side is the ratio of the quantity of heat removed from a fluid to the maximum heat removed. If flowrate increases the heat removal decreases so shell side efficiency decreases, where as the tube side flowrate is kept constant the heat removal increases so the tube side efficiency increases. If the flow rate of cold fluid increases the capacity rate ratio increases which in turn decreases the NTU, so Effectiveness decreaes with increaing Reynolds number (Cold) for Parallel flow heat echanger. In counter current flow heat exchanger, for immiscible systems, the effectiveness decreases with increasing the mass flow rate of cold fluid. For miscible systems, if the mass flow rate of cold fluid increases, the capacity rate ratio decreases which in turn increases the NTU, so effectiveness increases with increasing Reynolds number (Cold). 3.5.2 Effect of Variation of Composition From the Tables 3.1 to 3.10, the overall heat transfer coefficient for 9 % to 25% of Water-Water System, Kerosene-Water System, Toluene-Water System, Acetic acid-water System and Ethylene Glycol-Water System on volume basis almost increases with increasing in the mole fraction of system used for constant flow rate of the hot fluid. This is because decrease in the concentration of water increases the heat capacity of the tube side fluid and hence the heat transferred. Increase in composition decreases the tube outlet temperature because decrease in the concentration increases the specific heat value.

36 In the Figures 3.25 to 3.28 and Figures 3.50 to 3.53 plotted exchanger effectiveness versus flow rate of the cold fluid for 9% to 25% on volume basis for various miscible and immiscible systems, at constant flow rate of the hot fluid, show that the effectiveness increases with increase in the mole fraction of systems. From the Figures 3.20 to 3.23 and Figures 3.45 to 3.48, we observed that the efficiency increases with increasing in the mole fraction of miscible and immiscible systems for both parallel and counter current flow heat exchanger. 3.5.3 Nusselts Number (Cold) Vs Parallel Flow The Reynolds number (Cold) for different composition (9%, 10%, 20% and 25% on volume basis) of immiscible (Kerosene-Water, Toluene- Water) and miscible systems (Acetic acid-water, Ethylene Glycol-Water) is plotted against Nusselt number (Cold) to find the effect of varying flow rate and composition of cold side fluid on heat transfer coefficient of cold side fluid under parallel flow condition in the Figures 3.4 to 3.8. Figure 3.4 Nusselt Number (Cold) Vs Water-Water System Figure 3.5 Nusselt Number (Cold) Vs Kerosene-Water System

37 Figure 3.6 Nusselt Number (Cold) Vs Toluene-Water System Figure 3.7 Nusselt Number (Cold) Vs Ethylene Glycol-Water System Figure 3.8 Nusselt Number (Cold) Vs Acetic acid-water System 3.5.4 Nusselts Number (Hot) Vs Parallel Flow The Reynolds number (Cold) for different composition (9%, 10%, 20% and 25% on volume basis) of immiscible (Kerosene-Water, Toluene- Water) and miscible system (Acetic acid-water, Ethylene Glycol-Water) is plotted against Nusselt number (Hot) to indicate the effect of varying flow rate and composition of cold side on heat transfer coefficient of hot side under parallel flow condition in the Figures 3.9 to 3.13.

38 Figure 3.9 Nusselt Number (Hot) Vs Water-Water System Figure 3.10 Nusselt Number (Hot) Vs Kerosene-Water System Figure 3.11 Nusselt Number (Hot) Vs Toluene-Water System Figure 3.12 Nusselt Number (Hot) Vs Ethylene Glycol-Water System Figure 3.13 Nusselt Number (Hot) Vs Acetic acid-water System 3.5.5 Hot Efficiency Vs Parallel Flow The Reynolds number (Cold) for different composition (9%, 10%, 20% and 25% on volume basis) of immiscible (Kerosene-Water, Toluene-

39 Water) and miscible system (Acetic acid-water, Ethylene Glycol-Water) is plotted against efficiency of hot side fluid to find the effect of varying flow rate and composition of cold side on efficiency of hot side under parallel flow condition in the Figures 3.14 to 3.18. Figure 3.14 Hot Efficiency Vs Water-Water System Figure 3.15 Hot Efficiency Vs Kerosene-Water System Figure 3.16 Hot Efficiency Vs Toluene-Water System Figure 3.17 Hot Efficiency Vs Ethylene Glycol-Water System Figure 3.18 Hot Efficiency Vs Acetic acid-water System

40 3.5.6 Cold Efficiency Vs Parallel Flow The Reynolds number (Cold) for different composition (9%, 10%, 20% and 25% on volume basis) of immiscible (Kerosene-Water, Toluene- Water) and miscible system (Acetic acid-water, Ethylene Glycol-Water) is plotted against efficiency of cold side fluid to find the effect of varying flow rate and composition of hot side on efficiency of cold side under parallel flow condition in the Figures 3.19 to 3.23. Figure 3.19 Cold Efficiency Vs Water-Water System Figure 3.20 Cold Efficiency Vs Kerosene-Water System Figure 3.21 Cold Efficiency Vs Toluene-Water System Figure 3.22 Cold Efficiency Vs Ethylene Glycol-Water System

41 Figure 3.23 Cold Efficiency Vs Acetic acid -Water System 3.5.7 Effectiveness Vs Parallel Flow The variation in Reynolds number (Cold) for different composition (9%, 10%, 20% and 25% on volume basis) of immiscible (Kerosene-Water, Toluene-Water) and miscible system (Acetic acid-water, Ethylene Glycol- Water) on effectiveness to indicate the effect of varying flow rate and composition of cold side on effectiveness under parallel flow condition is shown in Figures 3.24 to 3.28. Figure 3.24 Effectiveness Vs Reynolds Number (Cold) for Water- Water System Figure 3.25 Effectiveness Vs Reynolds Number (Cold) for Kerosene- Water System

42 Figure 3.26 Effectiveness Vs Reynolds Number (Cold) for Toluene- Water System Figure 3.27 Effectiveness Vs Reynolds Number (Cold) for Ethylene Glycol-Water System Figure 3.28 Effectiveness Vs Reynolds Number (Cold) for Acetic acid-water System 3.5.8 Nusselt Number (Cold) Vs Counter Current Flow The Reynolds number (Cold) for Water-Water system and different composition (9%, 10%, 20% and 25% on volume basis) of immiscible (Kerosene-Water, Toluene-Water) and miscible system (Acetic acid-water, Ethylene Glycol-Water) are plotted against Nusselt number of cold side to find the effect of varying flow rate and composition of cold side on heat transfer coefficient of cold side under counter current flow condition in the Figures 3.29 to 3.33.

43 Figure 3.29 Nusselt Number (Cold) Vs Water-Water System Figure 3.30 Nusselt Number (Cold) Vs Kerosene-Water System Figure 3.31 Nusselt Number (Cold) Vs Toluene-Water System Figure 3.32 Nusselt Number (Cold) Vs Ethylene Glycol-Water System Figure 3.33 Nusselt Number (Cold) Vs Acetic acid-water System

44 3.5.9 Nusselt Number (Hot) Vs Counter Current Flow The effect of mass flow rate of cold fluid in terms of Reynolds number (Cold) for different composition (9%, 10%, 20% and 25% on volume basis) of immiscible (Kerosene-Water, Toluene-Water) and miscible system (Acetic acid-water, Ethylene Glycol-Water) is plotted against Nusselt number (Hot) to indicate the effect of varying flow rate and composition of cold side on heat transfer coefficient of hot side under counter current flow condition in the Figures 3.34 to 3.38. Figure 3.34 Nusselt Number (Hot) Vs Water-Water System Figure 3.35 Nusselt Number (Hot) Vs Kerosene-Water System Figure 3.36 Nusselt Number (Hot) Vs Toluene-Water System Figure 3.37 Nusselt Number (Hot) Vs Ethylene Glycol-Water System

45 Figure 3.38 Nusselt Number (Hot) Vs Acetic acid-water System 3.5.10 Hot Efficiency Vs Counter Current Flow The Reynolds number (Cold) for different composition (9%, 10%, 20% and 25% on volume basis) of immiscible (Kerosene-Water, Toluene- Water) and miscible system (Acetic acid-water, Ethylene Glycol-Water) is plotted against efficiency of hot side to find the effect of varying flow rate and composition of cold side on efficiency of hot side under counter current flow condition in the Figures 3.39 to 3.43. Figure 3.39 Hot Efficiency Vs Water-Water System Figure 3.40 Hot Efficiency Vs Kerosene-Water System

46 Figure 3.41 Hot Efficiency Vs Toluene-Water System Figure 3.42 Hot Efficiency Vs Ethylene Glycol-Water System Figure 3.43 Hot Efficiency Vs Acetic acid-water System 3.5.11 Cold Efficiency Vs Counter Current Flow The Reynolds number (Cold) for different composition (9%, 10%, 20% and 25% on volume basis) of immiscible (Kerosene-Water, Toluene- Water) and miscible system (Acetic acid-water, Ethylene Glycol-Water) is plotted against efficiency of cold side to find the effect of varying flow rate and composition of hot side on efficiency of cold side under counter current flow condition in the Figures 3.44 to 3.48.

47 Figure 3.44Cold Efficiency Vs Water-Water System Figure 3.45 Cold Efficiency Vs Kerosene-Water System Figure 3.46Cold Efficiency Vs Toluene-Water System Figure 3.47 Cold Efficiency Vs Ethylene Glycol-Water System Figure 3.48 Cold Efficiency Vs Acetic acid-water System

48 3.5.12 Effectiveness Vs Counter Current Flow The variation in Reynolds number (Cold) for different composition (9%, 10%, 20% and 25% on volume basis) of immiscible (Kerosene-Water, Toluene-Water) and miscible system (Acetic acid-water, Ethylene Glycol- Water) on effectiveness to indicate the effect of varying flow rate and composition of cold side on effectiveness under counter current flow condition is shown in Figures 3.49 to 3.53. Figure 3.49Effectiveness Vs Reynolds Number (Cold) for Water- Water System Figure 3.50 Effectiveness Vs Reynolds Number (Cold) for Kerosene- Water System Figure 3.51Effectiveness Vs Reynolds Number (Cold) for Toluene- Water System Figure 3.52 Effectiveness Vs Reynolds Number (Cold) for Ethylene Glycol-Water System

49 Figure 3.53 Effectiveness Vs Reynolds Number (Cold) for Acetic acid-water System 3.6 SIMULATION USING ARTIFICIAL NEURAL NETWORK 3.6.1 Introduction The General Regression Neural Network (GRNN) is a universal approximator for smooth functions, so it should be able to solve any smooth function-approximation problem given enough data. General regression neural networks perform regression where the target variable is continuous. The description of GRNN is given below. 3.6.2 Input Layer A layer of neurons that receives information from external sources, and passes this information to the network for processing. These may be either sensory inputs or signals from other systems outside the one being modeled. 3.6.3 Hidden Layer A layer of neurons that receives information from the input layer and processes them in a hidden way. It has no direct connections to the

50 outside world (inputs or outputs). All connections from the hidden layer are to other layers within the system. 3.6.4 Output Layer out of the system. A layer of neurons that receives processed and sends output signals 3.6.5 Bias Acts on a neuron like offset. The function of the bias is to provide a threshold for the activation of neurons. The bias input is connected to each of the hidden and output neurons in a network. 3.6.6 Input-Output Mapping The input/output mapping of a network is established according to the weights and activation functions of their neurons in input, hidden and output layers. The number of input neurons corresponds to the number of input variables in the network, and the number of output neurons is the same as the number of desired output variables. The number on neurons in the hidden layer(s) depends on the particular neural network application. 3.6.7 Pattern Classifier The general multilayer neural network classifier structure for the simulation is shown in Figure 3.54. The actual ANN classifier structure used for this problem is shown in Figure 3.55. The ANN has 7 neurons in the input layer and 8 neurons in the output layer. The 8 neurons in the output layer can handle 256 outputs and will be sufficient for this work. The number of

51 neurons in the hidden layer is 29. So the ANN structure boils down to 7:29:8. The ANN is adaptively trained to update the weights and the bias by gradient descent method by mean square error performance. Figure 3.54 General Multilayer Neural Network Classifier The classifier structure for this work and the training pattern for 1000 epochs are shown in Figure 3.55. In classifier the first block indicates the input layer comprising of 7 neurons, the central block indicates the hidden layer comprising of 29 neurons and the last block indicates the output layer comprising of 8 neurons respectively. The blocks between the input layer and the middle layer indicate the weight factor (1W {1, 1} associated with input node and bias input (b{1}acts as a neuron like offset. The blocks between the input layer and output layer indicates the weight factor (LW {2, 1}) associated with the hidden layer and Bias input (b{2}) acts as a neuron like offset.

52 Figure 3.55 Pattern Classifier for Shell and Tube Heat Exchanger 3.7 COMPARISON OF SIMULATION OUTPUT WITH THE EXPERIMENTAL DATA FOR SHELL AND TUBE HEAT EXCHANGER The simulation is carried out using ANN to predict Nusselts number of the cold fluid (N Nu ), effectiveness (ε), cold side efficiency (η c ) and hot side efficiency (η h ) for the Shell and Tube Heat Exchanger. A comparison is made to show the performance characteristics of heat exchanger of the simulation output using ANN with the experimental data which is given in Tables 3.11 and 3.12. The table indicates that the simulation results are very well agreed with the experimental data.