To investigate Heat Loss of a Fluid flowing through a Pipeline for Turbulent Flow

Transcription

1 ISSN: Volume, Issue 9, Januay 206 To investigate Heat Loss of a Fluid flowing though a Pipeline fo Tubulent Flow Maheshkuma Mauti Patil, Maiappan D. Nada 2, Suhas A. Uthale 3 PG Student, Mechanical Eng. Dept., Pillai Hoc College of Engg. & Tech., Rasayani, MH, India 2 Pofesso, Mechanical Eng. Dept., Pillai Hoc College of Engg. & Tech., Rasayani, MH, India 3 Assistant Pof., Mechanical Eng. Dept, Pillai Hoc College of Engg. & Tech., Rasayani, MH, India Abstact: This pape investigates heat enegy losses of fluid while flowing though insulated long distance pipeline. The losses of heat enegy at diffeent steps of fluid flowing though insulated pipe line with tubulent flow chaacteistics ae pesented. In this poject steam is a woking fluid which is geneated in the boile and teminated pocess house. The study is caied out in thee steps including development of theoetical model of the poblem followed by solution of the defined poblem obtaining the output fo heat loss fo diffeent values of thickness of insulation, ANSYS steady state themal was used and fo obtaining the value of outlet tempeatue of steam at citical thickness of insulation ANSYS Fluent was used. Fo validation of ou computational fluid dynamics (CFD) using ANSYS Fluent solution, the same model will be analyzed in using MATLAB. This study can be put to application in fast assessment of situation of heat dissipation duing Steam tansfe fom one place to anothe passing though cold atmospheic conditions using MATLAB instead of much complex simulation softwae. Keywods: Heat Enegy loss, Pipe Design, Insulation Mateial, Citical thickness of insulation, ANSYS modelling and veification, Numeical simulation in MATLAB I. INTRODUCTION Pipeline tanspot is the tanspotation of goods (geneally fluids) though a pipe. A quick detemination the heat loss of a pipeline system has always been a difficult poblem fo enginees and pipe netwok designes as pipeline systems ae complex and the ambient envionment is highly vaiable. Mass flow ate though the pipe and the powe equie fo a desiable flow ate ae highly dependent on tempeatue of the fluid it is caying. The pipe mateial and the insulation mateial have geat effects on convective and conductive heat tansfe inside the pipe wall. At a paticula insulation thickness, viscous dissipation exactly equal to conductive heat loss. Steam stays at its ideal tempeatue thoughout the length of pipeline and the need fo heating stations is educed. Fom a design standpoint, this insulation thickness is called optimal. In this poject steam is a woking fluid and steam is geneated in the boile, the geneated steam supplying though insulated pipe line. The steam is passing though long distance insulated pipe line and teminated pocess house. The pocess house consists of sizing, dyeing, bleaching, pinting pocess etc. in the textile industy. The tempeatue of steam at boile house (503K) and pocess houses (426K) ae shown with huge diffeence. This tempeatue diffeence shows thee is huge heat tansfe dissipation takes place duing steam flowing though pipe line. The poject investigation of 206, IJAERA - All Rights Reseved 376

2 steam enegy losses and to minimize heat enegy losses by designing citical thickness of insulating mateial (glass wool). The following study is caied out in thee steps including development of theoetical model of the poblem followed by solution of the defined poblem obtaining the output fo heat loss fo diffeent values of thickness of insulation, steady state themal was used and fo obtaining the value of outlet tempeatue of steam at citical thickness of insulation ANSYS Fluent was used. Fo validation of ou computational fluid dynamics (CFD) using ANSYS Fluent solution, the same model will be analyzed in using MATLAB. This study can be used in fast assessment of situation of heat dissipation. Simulation can be done at the time of steam tansfe fom one place to anothe passing though cold atmospheic conditions by using MATLAB instead of much complex simulation softwae. Poblem Statement Significance of steam is mandatoy in the pocess industies like cement dy plant, suga plant, fetilize, and textile etc.; Geneation of steam takes place in the boile house. Geneated steam is supplying to the pocess house though insulated pipe line. When steam flows though insulated pipe lines it loses its heat enegy though pipe line and insulato. Which may lead to steam will become waste in the pocess industy. So necessay to detemine citical insulato thickness to avoid heat loses duing steam flows though insulato pipe line with unifom velocity. Solution to the above defined poblem statement can be achieved though these steps: Solution Methodology Paametic Modelling in ANSYS: With the help of ANSYS5 a paametic model study was caied out by which the heat tansfe at vaious thickness of insulation was caied out. The output was taken fom and the plot of heat tansfe with incease in thickness of insulation was obtained. Fo tempeatue dop the model of the pipe paametic analysis was pefomed in ANSYS fluent and the tempeatue dop fo vaious thickness of insulation was obtained. Model Development MATLAB Pogamming: Fomulating a mathematical model fom the given poblem statement is most impotant pospect of engineeing. So fo this scenaio, instead of Solving Log Mean Tempeatue Diffeence equation which is found by applying end bounday value to the enegy equation govening heat tansfe, numeically evaluation of the diffeential equation using a suitable solving scheme is caied out. The solution of the poblem is obtained in MATLAB. The pogam was witten in MATLAB fo obtaining the citical thickness of insulation. Theoetical Model Below Figue shows a pat of the pipeline, whee the inne and oute sufaces ae exposed to hot steam and ai espectively. The heat tansfe pocess includes the convection inside the pipe, the conduction though the pipe, and the convection outside the pipe. The pipe geomety is shown in the Figue below , IJAERA - All Rights Reseved 377

3 Figue : Heat tansfe pocess and tempeatue distibution though pipe wall Accoding to the themal esistance theoy, the heat tansfe ate though the pipe wall is pesented as, q 2 L h ln 2 k 2 L 2 ln ( t k t 6 ) ln L 2 k L 2 L 4 h 0 R f..() Whee, t stands fo the tempeatue, the adius, k the themal conductivity, h the convection heat tansfe coefficient, and L the length espectively. In pactical analysis, although the outside ai tempeatue t6 is usually consideed as a constant, the inside steam tempeatue t is a vaiable since it vaies along the flow diection. By analysis and calculation, it is concluded that the tempeatue Diffeence (t - t6) may be assumed to be the log mean tempeatue diffeence. Model Analysis Validation: The value obtained fom the citical thickness of insulation was consideed and the geomety was changed and the new geomety with the thickness of insulation equal to the citical value of thickness of insulation was made. The CFD analysis was pefomed in ANSYS Fluent and the aveage tempeatue dop of the steam along m length of the pipe was found out. II. LITERATURE REVIEW Heat enegy tansfe in pipeline has been evaluated fo almost 60 yeas. Nusselt's pape published in 90 was the fist pape in analyzing at scientific level. Late Duing subsequent yeas diffeent investigatos and scientists had studied flow though pipe fo vaious fluids. As a esult of this elation of Nusselt numbe with Reynold's numbe and Pandtl numbe wee fomulated [2]. Diessle consideed the compaative appoximations as like Gaetz and gave the analytical solution fo the poblem fo fully developed pipe flow in which fluid popeties vay along the adius []. Heat tansfe though pipe is dependent on wall thickness of the boundaies which was shown by by Adekunle O. Adelaga, JacoDiki and Josua P. Meya [9] Maintaining the Integity of the Specifications. CFD simulation of small and medium gauge 90 cicula bend was done by Wan Kai and Wang Ping. They used standad k-ε model with FLUENT softwae on lage diamete CFD numeical 206, IJAERA - All Rights Reseved 378

4 simulation of ai flow in a 90 twisted tube, ae thee dimensional stess field and velocity field in the pipe. To exploe non-change law of fully developed pipe flow though CFD numeical simulation on lage-diamete flue gas, lays the foundation fo analysis and numeical simulation of non-cicula coss section [7]. III. OBJECTIVES To study flow of the steam though insulato pipe line and obseve the steam flow type. To identify the themal enegy loses of steam while flowing though insulato pipe line: The analysis will pefom in ANSYS consideing thickness of insulation as a paamete which can be change and heat losses at diffeent thickness of insulation can be obtain. The value o f the citical thickness of insulation to be found out. And also heat loss at citical thickness of insulation will be found out. The same analysis will be pefoming in MATLAB simulation softwae (Simscape). Fom this simulation will get the value of the citical thickness of insulation and heat loss at citical thickness of insulation. To obseve tempeatue loses and pessue loses of the steam fom boile house to pocess houses: The evaluation of the Tempeatue loss ANSYS softwae will be used. The esults will obtain which can be used to pedict the tempeatue loss along the length of the pipe fo industial pipelines which cay steam ove long distances fo industial applications. IV. PIPELINE DESIGN Factos to be consideed in designing A. Industy Codes and Standads B. Effect of pessue on fluid flow though pipe The pimay effect of fiction in fluid flow is pessue dop, so any significant tempeatue change in the fluid is because of heat tansfe. The aveage velocity Vavg at steam wise coss-section is detemined fom the equiement that the consevation of mass pinciple be satisfied. That is,. m VavgAc Ac u( ) dac (2) Whee m is the mass flow ate, is the density, Ac is the coss-sectional aea, and u() is the velocity pofile. Then the aveage velocity fo incompessible flow in a cicula pipe of adius R can be expessed as, R R u( ) dac u( )2d 2 Vavg u( ) d 2 2 (3) Ac R R Ac , IJAERA - All Rights Reseved 379 0

5 Theefoe, when we know the flow ate o the velocity pofile, the aveage velocity can be detemined easily. C. Tubulent Flow Fo tubulent steam the entance length is shote due to the additional tanspot mechanism acoss the coss section. In this way in odinay passage such as hydodynamic lengths in tubulent steam ae 0-5 times tube diamete and themal entance lengths ae consideably little than that. Theefoe, in most of the engineeing situations whee in L/D 50, we use coelations fo fully developed flow condition. Connection fo tubulent steam is aanged elies on upon whethe the inside wall of the tube is smooth / ough. D. Smooth Tubes The ealiest coelation fo tubulent heat tansfe in a smooth tube is given by Dittus and Boelte, McAdams and Colbun. A common fom to be used fo fluids with P>0.5 is, Nu 0.023Re P.. (4) The most usual we use this coelation, but in usual pactice it is used even when the flow is in tansit condition between lamina flow and tubulent flow fo lack of bette coelations. That is slightly moe accuate a moden coelation fo Nusselt no. is given by as follows, f (Re 000) P Nu 8.. (5) / 2 2 / 3 2.7[( f / 8) (P )] Fo low Pandtl numbe, special coelations to be used fo conditions. Physical popeties to be used in these coelations ae evaluated at the aveage of the inlet and exit tempeatues of the fluid. We know that f is Dacy Fiction Facto and accoding to Petukhov s it is evaluated as follows, f.. (6) 2 [0.790ln(Re).64] This esult is good fo tubulent flow in smooth pipe fo Re 5 x 0 6. E. Themal Insulation Themal insulation is chaacteized as the eduction of heat tansfe between objects in themal contact o in scope of adiative impact. Heat steam is an inescapable outcome of contact between objects of vaying tempeatue. Themal insulation gives a egion of insulation in which themal conduction is diminished and themal adiation is eflected as opposed to consumed by the lowe-tempeatue body. The insulating capability of a mateial is measued with themal conductivity (k). Low themal conductivity is equal to high insulating capability (R-value). In themal engineeing, othe citical popeties of insulating mateials ae poduct density (ρ) and specific heat capacity (c) , IJAERA - All Rights Reseved 380

6 Figue 2: Tempeatue distibution tend in pipe wall and fluid Accoding to the themal esistance theoy, the heat tansfe ate though the p ipe wall is pesented as, q 2 L h ln 2 2 k ln L 2 ( t k t 6 ) ln L 2 k L 2 L 4 h 0 R f..(7) By analysis and calculation, it is concluded that the tempeatue diffeence (t - t6) may be assumed to be the log mean tempeatue diffeence. In above equation, thee ae thee unknown vaiables, namely, inne convective heat tansfe coefficient h, oute convective heat tansfe coefficient h2, and the oute wall tempeatue tout. V. ANSYS MODELING AND VERIFICATION Analysis in Steady State Themal fo obtaining Citical Thickness of Insulation A. Pe-pocessing: Engineeing Data In the engineeing data the details fo the mateials consideed fo analysis wee povided thei popeties. Fo themal analysis the themal conductivity of each mateial is a must. ) Geomety The geomety of the pipe with insulation and foil was made in ANSYS design modele. Fo simplification and eduction of computational time the /4 th model of the pipe was consideed fo ANALYSIS. Multiplying the obtained esults by 4 will give the same esults of that when consideing the full model fo ANALYSIS. The model is shown in the figue below. Each and evey dimension of the pipe was taken as a paamete which can be changed extenally fo obtaining outputs at vaious thickness of insulation , IJAERA - All Rights Reseved 38

7 Figue 3: /4 th model of the pipe Details of Geomety Inne Radius of steel: 0.07 m (Constant) Oute Radius of steel pipe: 0.08 m (Constant) Inne adius of insulation: 0.08 m (Constant) Oute adius of insulation: m (Vaiable Paamete) Inne adius of foil: m (Vaiable Paamete) Oute adius of foil: m (Vaiable Paamete) 2) Meshing The next step is to divide the geomety into finite elements fo poblem simplification. The edge sizing had been povided to all the edges of the geomety to obtain a good quality mesh. Sweep method was used to give a sweep mesh along the whole length of the pipe with the paticula numbe of divisions along the length fo each mateial i.e. on pipe, insulation and foil. Numbe of divisions fo edge sizing A: 7 (Constant) Numbe of divisions fo edge sizing B: 2 (Vaiable Paamete) Numbe of divisions fo edge sizing C: 40 (Constant) Numbe of divisions fo edge sizing G: 2 (Constant) Mapped Face Meshing fo a unifom mesh along the whole geomety Numbe of divisions in sweep fo all the 3 bodies: Default (As detemined by ANSYS). The mesh obtained is as shown in the figue below. Figue 4: Mesh Geneated with the settings povided 206, IJAERA - All Rights Reseved 382

8 3) Bounday Conditions At the inne wall of the pipe the tempeatue at which steam is flowing alo ng the pipe was consideed. The oute suface of the foil was given a convection of 2 W/m 2 K at atmospheic tempeatue of 28 degee Celsius. B. Solution The solution was obtained by ight clicking on the solution and clicking solve, C. Post Pocessing Figue 5: Solution Results fo tempeatue plot consideing /4 th model of pipe The esults obtained fo the ANSYS steady state heat tansfe is shown in the Figue 2 fo abitay value of thickness of insulation. /4 th of the model is used fo analysis fo saving the computational time. The esults fo the model can be multiplied by 4 to obtain the tue esult. Howeve the thickness of insulation can be given as a paamete and can be changed to obtain heat loss fo vaious thickness of insulation. The gaph shows the tend in which the heat loss vaies with the thickness of insulation. Figue 6: Tempeatue plot consideing /4 th model and abitay thickness of insulation The esult geneated above is only fo thickness of insulation to obtain multiple esults of heat loss 206, IJAERA - All Rights Reseved 383

9 fo vaious thicknesses of insulation paametes wee used. The geomety was defined in such a way that the dimensions of the insulation and the foil can be changed extenally and can be incopoated in the model athe than changing the geomety fom the design modelle again and again and solving it fo each value. The pocedue fo the same is explained with the help of a table below. Figue 7: Paametes which ae constant and vaying In the table it can be seen that paamete P3 and P4 epesents the oute adius of the insulation and the foil. The paamete P8 gives the numbe of divisions that has to be given to the thickness of insulation fo obtaining a mesh which gives accuate esults. As the insulation thickness inceases, it should be povided highe numbe of divisions fo accuate esults. Rest of the paametes ae kept constant as descibed ealie. The paamete P7 gives the heat loss at diffeent values of thickness of insulation. Gaph : Heat loss Vs Extenal Radius of Insulation 206, IJAERA - All Rights Reseved 384

10 As obseved fom the gaph, fom point A the insulation thickness inceases the heat loss inceases. Thee comes a point B at which the thickness of insulation is such that it gives maximum heat loss which is W. Beyond that point with futhe incease in the thickness of insulation, the heat loss stats deceasing again. With futhe incease of thickness of insulation we will obtain vaious choices of thickness of insulation whee the heat loss is less. Now the extent at which the insulation thickness is inceased depends upon the othe factos like saving the cost o having a taget tempeatue at outlet. Highe the thickness of insulation beyond point C moe will be the tempeatue of steam at outlet. Analysis in ANSYS Fluent fo obtaining tempeatue dop along the length of pipe A. Pe Pocessing Geomety: The full model of a 0 m along pipe was made along with the insulation and foil ove it as shown in the figue below. The citical thickness of insulation obtained fom the pevious analysis was consideed hee and the insulation was given that paticula dimension i.e. 6mm thickness giving an oute diamete of insulation to be 72 mm. The model of the same is shown in the figue below. Figue 8: Model The model contains a steam domain, a steel pipe ove it and insulation connected to the steel pipe and finally a foil ove the insulation. Meshing: Face sizing command to give element length of 3mm to the steam domain Sweep Method to obtain a sweep mesh along the length of the pipe with the numbe of divisions to be , IJAERA - All Rights Reseved 385

11 Figue 9: Named selection and application of bounday conditions on them Bounday Conditions: Poviding named selections to the each and evey component and egion of the geomety gives an ease to apply bounday conditions and inputs on the geomety. Following ae the inputs, bounday conditions and mateials assignments that ae to be povided. Fluid: Mateial Assigned: Wate Vapou fom ANSYS Fluent Database Consides themal conductivity of steam and vaious othe popeties equied fo analysis. Steel: Mateial Assigned: Steel fom ANSYS Fluent Database consideing themal conductivity of steel. Insulation: Glass Wool consideing themal conductivity of insulation assigned manually to the fluent database which is 0.8 W/mK. Foil: Aluminium consideing themal conductivity of foil assigned manually to the fluent database which is 5 W/mK. Inlet: The steam is known to ente the pipe at a velocity of 25 m/s and a pessue of 3.03 ba and with an initial tempeatue of 503 K. Outlet: This is assigned to obtain the output at the othe end of the pipe i.e. whee the steam exits the pipe. Steel, Foil and Insulation wall: These walls ae assumed to be adiabatic that is thee is no heat tansfe though the wall ends of these mateials. Oute Wall: Hee the effect of oute atmosphee with convection at ambient tempeatue is incopoated which is 2W/m 2 K at 30 K. B. Solution The above poblem was solved consideing k epsilon model which is suitable fo tubulent flows. Two-equation tubulence models allow the detemination of both, a tubulent length and time scale by solving two sepaate tanspot equations. The standad k epsilon model in ANSYS FLUENT falls within this class of models and has become the easy of pactical engineeing flow calculations in the time since it was poposed by Launde and Spalding. Robustness, economy, and easonable accuacy fo a wide ange of tubulent flows explain its populaity in industial flow and heat tansfe 206, IJAERA - All Rights Reseved 386

12 simulations. It is a semi-empiical model, and the deivation of the model equations elies on phenomenological consideations and empiicism. The standad k - epsilon model is a model based on model tanspot equations fo the tubulence kinetic enegy (k) and its dissipation ate (epsilon). The model tanspot equation fo is deived fom the exact equation, while the model tanspot equation fo was obtained using physical easoning and beas little esemblance to its mathematically exact countepat. In the deivation of the k epsilon model, the assumption is that the flow is fully tubulent, and the effects of molecula viscosity ae negligible. The standad k epsilon model is theefoe valid only fo fully tubulent flows. As the stengths and weaknesses of the standad k epsilon model have become known, modifications have been intoduced to impove its pefomance. Two of these vaiants ae available in ANSYS FLUENT: the RNG k epsilon model and the ealizable k epsilon model. C. Post Pocessing The tempeatue dop was obtained fom ANSYS Fluent as shown in the gaph below. It shows the tempeatue dop of steam along the length of the pipe fo the citical thickness of insulation of 6 mm. The tempeatue dop is found out to be 30 K fo a length of 0 m. Figue 0: Tempeatue plot along the length of the pipe The tempeatue plot along the length of the pipe is as shown in the gaph below, 206, IJAERA - All Rights Reseved 387

13 Gaph 2: Tempeatue along the length of the pipe VI. NUMERICAL SIMULATION IN MATLAB The model in this poject is a steam pipeline segment. Steam entes the pipeline segment at a fixed tempeatue, 503 K with a fixed mass flow ate,, whee: is the volumetic flow ate of steam though the pipe and is the mass density of steam enteing the pipeline segment. To model and solve the poblem in this poject we ae making the following viable assumptions: Flow though the pipeline is assumed to develop though its couse. Velocity pofile of the steam emains constant along the pipeline length. Steam is assumed to be compessible and in single phase. Shea stess is popotional to the shea stain. Mass density vaies with both tempeatue and pessue. Pipe wall is thin and its mateial a good themal conducto. As we assume that pipe mateial is good conducto of heat, we can safely ignoe its themal esistance. The combined themal esistance is then simply the sum of the insulation and Aluminum foil contibutions, Rins and RAl foil , IJAERA - All Rights Reseved 388

14 A. MATLAB model constuction B. Simscape Elements Infomation Figue : The Simscape Model Themal Conductivity of wate vapos o steam= 0.26 W/mK Inne Radius of tube= 70 mm. Length of tube= 0 m Oute Radius of tube=80 mm Themal Conductivity of steel= 6.27 W/mK Coefficient of heat tansfe between ai and foil suface = 2 W/m 2 K Tempeatue of wate vapos o Steam= 503 K Ambient Tempeatue= 30 K C. Details of the Simscape Elements Fo defining each element in the model following paametes wee given: Tempeatue Resevoi: Input paamete:. Resevoi tempeatue = 503 K 2. Inlet pipe coss-sectional aea = m , IJAERA - All Rights Reseved 389

15 Mass Flow Rate Senso (TL): Input Paamete:. Mass flow ate =. kg/s 2. Chaacteistic longitudinal length = 0 m 3. Pipe coss-sectional aea = m 2 Pipe (TL): Input Paamete:. Geomety: Longitudinal length = 0 m Hydaulic diamete = 0.40 m Coss-sectional aea = m 2 2. Viscous Fiction: Aggegate equivalent length of local esistances = m Shape facto = 64 Intenal suface absolute oughness =.5*0-5 Lamina flow uppe magin = 2000 Tubulent flow lowe magin = Heat Tansfe: Lamina egime Nusselt numbe coelation coefficients = [ ] Tubulent egime Nusselt numbe coelation coefficients = [ ] 4. Effect and Initial Conditions: Fluid dynamic compessibility = off Initial fluid tempeatue inside the pipe = 503 K Conductive Heat Tansfe Foil and insulation: Input Paamete:. Thickness of foil= 2 mm 2. Themal conductivity fo the foil= 5 W/mK 3. Thickness of insulation= Vaies fo diffeent values 4. Themal Conductivity of insulation = 0.8 W/mK Themal Liquid Setting (TL): Input Paamete:. Valid pessue-tempeatue egion paametization = By Minimum and Maximum values 2. Minimum valid tempeatue = 545 K 3. Maximum valid tempeatue = 475 K 4. Minimum valid pessue = 0.ba 5. Maximum valid pessue = 500 ba 6. Minimum themal conductance = 0.00W/K 7. Atmospheic pessue = atm In the above ceated model one subsystem is also ceated, fo upsteam tempeatue senso. Figue 2: Upsteam tempeatue senso sub-systems D. Results in MATLAB 206, IJAERA - All Rights Reseved 390

16 The mathematical model of the same is pogammed in MATLAB and the scipt was un to find the value of citical thickness of insulation. The thickness of insulation was found to be 06 mm whee thee is maximum heat loss of W. Gaph 3: Static Tempeatue at the cente line along the length of pipe VI.5 Veification and Validation between MATLAB and ANSYS The gaph shows a coelation between the heat loss tends obtained fom MATLAB and ANSYS esults. It was obseved that thee was vey less diffeence obtained between the two. Hence Fom the pocedue discussed one can easily find out the thickness of insulation ove a pipe caying steam at long distance. Gaph 4: Coelation between heat loss tends in ANSYS and MATLAB VII. CONCLUSION Pipe design is of cucial impotance fo industies dealing with bulk fluid motion and tanspot design factos like diamete, thickness and mateial selection ae to be chosen esoteically within 206, IJAERA - All Rights Reseved 39

17 economic and industial capability constaints. The NPS and ASME codes discussed in above epot ae pesent industial standads fo pipe design. Othe than design it is also necessay that the fluid should not change its state o popeties while tanspotation. To pevent the same pipe insulation is of exteme impotance. Gaph 5: Heat loss Vs Extenal Radius of Insulation (ANSYS) As obseved fom the gaph, fom point A the insulation thickness inceases the heat loss inceases. Thee comes a point B at which the thickness of insulation is such that it gives maximum heat loss which is W. Beyond that point with futhe incease in the thickness of insulation, the heat loss stats deceasing again. With futhe incease of thickness of insulation we will obtain va ious choices of thickness of insulation whee the heat loss is less. Now the extent at which the insulation thickness is inceased depends upon the othe factos like saving the cost o having a taget tempeatue at outlet. Highe the thickness of insulation beyond point C moe will be the tempeatue of steam at outlet. The analysis was pefomed in ANSYS consideing thickness of insulation as a paamete which can be changed and heat losses at diffeent thickness of insulation can be obtained. The value of the citical thickness of insulation was found out to be 6 mm. Heat loss at citical thickness of insulation is found to be W. The mathematical model of the same is pogammed in MATLAB and the scipt was un to find the value of citical thickness of insulation. The thickness of insulation was found to be 6 mm, whee thee is maximum heat loss of W. The poblem was also analyzed in ANSYS fluent fom which the tempeatue dop at the pipe outlet was obtained and fo the citical thickness of insulation it was obseved that the tempeatue dops to 30 0 K pe 0 metes. It can be seen that the esult obtained fom MATLAB lies in the egion of pecision of the esult which was obtained fom ANSYS fluent. Since the esult of the MATLAB is found out analytically it can be consideed as moe accuate. The evaluation of the tempeatue loss though ANSYS Softwae was caied out. The esults obtained can be used to pedict the tempeatue loss along the length of the pipe fo industial pipelines which cay steam ove long distances fo industial applications , IJAERA - All Rights Reseved 392

18 VIII. SCOPE OF THE PROJECT In pocess industies like Textile, cement, suga etc., Steam is used fo seveal pocesses of manufactuing opeations. Steam plays an impotant ole in the continuous pocess industies. Pocess industies faces the poblem of etain the heat enegy of steam while using in the manufactuing pocess and to pevent the losses of heat enegy though citical designing of pipe line and insulato of pipe line and boile while steam flows heat loss though these pipes. To detemination the heat loss of a pipeline system has always been a difficult poblem fo enginees and pipe netwok designes due to pipeline systems ae complex and the ambient envionment is highly vaiable. Mass flow ate though the pipe and the powe equie fo a desiable flow ate ae highly dependent on tempeatue of the fluid caies and flows though pipe line. To change pipe mateial and insulato mateial, to incease the pefomance of enegy stoage of steam while flows fom boile house to pocess plant and optimize the pipe design with consideation of economic factos. IX. REFERENCES [] R Diessle, Eian C.S, Analytical and Expeimental Investigation of Fully Developed Tubulent Flow of Ai in a Smooth Tube with Heat Tansfe with Vaiable Fluid Popeties, NACA TN-2629, 952. [2] B. S. Petukhov, Heat Tansfe and fiction in Tubulent Pipe Flow with Vaiable Physical Popeties, 970. [3] T.F. Lin, J.C. Kuo, Tansient conjugated heat tansfe in fully developed lamina pipe flows, Intenational Jounal of Heat and Mass Tansfe, May 988. [4] Scott Stolpa, Apil 30, 2004 Tubulent Heat Tansfe. [5] J.S. Jayakuma, S.M. Mahajani, J.C. Mandal, P.K. Vijayan, and RohidasBhoi, Expeimental and CFD estimation of heat tansfe in helically coiled heat exchanges, Chemical Engg Reseach and Design, [6] Xiaowei Zhu, Huui Tang, Hua Li, Jiahua Hong, Songyuan Yang, Theoetical and Numeical Analysis of Heat Tansfe in Pipeline System, APCOM & ISCM, Dec 203. [7] Wan Kai and Wang Ping, CFD numeical simulation analysis of small and medium calibe 90 cicula bend, Intenational Confeence on Compute Science and Electonics Engineeing (ICCSE 203). [8] Abdul Mateen, Fully Developed Flow of Two Viscous Immiscible Fluids though a Channel with Heat Tansfe, IJERT, Vol.2 - Issue 0, Octobe 203. [9] Adekunle O. Adelaga, JacoDiki, Josua P. Meya, Effects of Thick-walled Pipes with Convective Boundaied on Lamina Flow Heat Tansfe Jounal of Applied Enegy, Oct 204. [0] R.K. Rajput, Heat & Mass Tansfe, S. Chand Limited, , IJAERA - All Rights Reseved 393