FLOW CHARACTERISTICS OF NANOFLUIDS CONTAINING TITANIA NANOPARTICLE IN ETHYLENE GLYCOL MOHAMAD ZANI BIN RAZALI

Transcription

1 i FLOW CHARACTERISTICS OF NANOFLUIDS CONTAINING TITANIA NANOPARTICLE IN ETHYLENE GLYCOL MOHAMAD ZANI BIN RAZALI This thesis is submitted in fulfillment of the requirements for the award of degree of Bachelor of Engineering (Chemical) Faculty of Chemical Engineering Universiti Teknologi Malaysia JANUARY 2015

2 v ABSTRACT Nanofluids can be defined as new class of fluids which is dispersed in base fluids with nano-sized particles suspended within them. From previous study, nanofluids has very unique and attractive features such as high thermal conductivity even at very low nanoparticles concentration, high enhancement of forced convective heat transfer, and a better long term of stability. Hence, this research was conducted in order to study the enhancement of nanofludis in stability and the effect of temperature to the viscosity of the nanofluids. The stability of nanofluids is investigated through visual observation for a period of time and the viscosity was analyzed by using Brookfield DV-II+ Pro Viscometer at different temperature. The first step was preparing a very stable titania nanofluids in ethylene glycol, and then were further stabilized by addition of surfactant which is gum arabic. In this experiment, several vial of nanofluids samples is mounted onto a horizontal and stable surface before mixing process is took place by using magnetic stirrer. The results showed that titania nanoparticle in ethylene glycol based fluids were stable for a week. Hence, with further stabilized with surfactant of GA, the nanofluids show a promising result with no sedimentation for more than a month. From the results obtained, the viscosity of the nanofluids decreased as the temperature increased. As a conclusion, these experimental results are consistent with the characteristics of the nanofluids.

3 vi ABSTRAK Nanofluids boleh didefinisikan sebagai pencapaian kelas yang moden di mana penguraiannya di dalam cecair asas dengan zarah yang bersaiz sangat kecil adalah bergantung sesama mereka. Dalam penyelidikan yang lepas, nanofluids mempunyai ciriciri yang sangat unik dan amat menarik seperti mempunyai kekonduksian haba yang sangat tinggi walaupun pada kepekatan zarah yang bersaiz kecil itu pada tahap yang rendah, mempunyai peningkatan perolakan pengaliran haba yang sangat tinggi dan mempunyai kestabilan yang baik dan dapat kekal dalam masa yang lama. Oleh itu, penyelidikan ini telah dilaksanakan bertujuan untuk menyediakan titania nanofluids yang sangat stabil di dalam ethylene glycol, dan dipertingkatkan lagi tahap kestabilan itu dengan penambahan gum arabic yang bertindak sebagai agen penstabilan yang sagat berkesan. Keputusan ujikaji menunjukkan titania yang bersaiz sangat kecil yang diuraikan dan disebatikan di dalam ethylene glycol adalah stabil untuk tempoh masa seminggu. Kemudian, nanofluids itu distabilkan lagi dengan penambahan agen penstabilan iaitu gum arabic, nanofluids menunjukkan keputusan yang memberangsangkan dimana nanofluids itu menjadi lebih stabil dan tidak menunjukkan sebarang pemendapan melebihi tempoh masa sebulan.

4 41 However, there are still several important clues indicating the mechanisms of heat transfer in nanofluids, which can be used in future research such as: i. the difference in the concentration scale is too small, the results are quite hard to be compare and analyze. The suggestion is to disperse the titania nanoparticles with larger difference of weight percent. ii. the nanofluids are should be produced in variation of ph in order to further study the effect of alkali and acid to the stability of the nanofluids as well as the thermal conductivity enhancement. iii. conduct the experiment in a heat exchanger equipment to further study the flow characteristics of the nanofluids and the enhancement of the nanofluids to the thermal conductivity as well as heat transfer coefficient.

5 42 REFERENCES Chein R. and Huang G. (2005). Analysis of microchannel heat sink performance using nanofluids. Applied Thermal Engineering. 25(17) Choi S. U. S. and Eastman J. A. (1995). Enhancing thermal conductivity of fluids with nanoparticles. ASME International Mechanical Engineering Congress & Exposition. Choi S. U. S. (1998). Nanofluid technology: current status and future research. Korea- U.S. Technical Conference on Strategic Technologies, Vienna, VA. Choi S. U. S., Zhang Z. G., Yu W., Lockwood F. E. and Grulke E. A. (2001). Anomalous thermal conductivity enhancement in nanotube suspensions. Applied Physics Letters. 79(14) Das S. K., Putra N., Thiesen P. and Roetzel W. (2003a). Temperature dependence of thermal conductivity enhancement for nanofluids. Journal of Heat Transfer Das S. K., Putra N., and Roetzel W. (2003b). Pool boiling characteristics of nano- fluids. International Journal of Heat and Mass Transfer. 46(5) Das S. K., Putra N., Thiesen P., and Roetzel W. (2003c). Temperature dependence of thermal conductivity enhancement for nanofluids. Transactions of the ASME. Journal of Heat Transfer. 125(4)

6 43 Eastman J. A., Choi S. U. S., Li S., Thompson L. J., and Lee S. (1996). Enhanced thermal conductivity through the development of nanofluids. Fall Meeting of the Materials Research Society (MRS), Boston, USA. Eastman J. A., Choi U. S., Li S., Soyez G., Thompson L. J. and DiMelfi R. J. (1999) Novel thermal properties of nanostructured materials. Materials Science Forum, Switzerland Eastman J. A., Choi S. U. S., Li S., Yu W., and Thompson L. J. (2001). Anomalously increased effective thermal conductivities of ethylene glycol-based nanofluids containing copper nanoparticles. Applied Physics Letters. 78 (6) Einstein A. (1906). A new determination of the molecular dimensions. Annalen Der Physik Etemad S. G., Heris S. Z. and Esfahany M. N. (2006). Experimental investigation of oxide nanofluids laminar flow convective heat transfer. International Communications in Heat and Mass Transfer. 33(4) Gabriel H. and Aryel H. (2013). Numerical study on heat transfer performance of a thermosyphon heat pipes using nanofluids. Energy conversion and management Ghadimi A., Saidur R. and Metselaar H. S. C. (2011). A review of nanofluid stability properties and characterization in stationary conditions. International Journal of Heat and Mass Transfer Haisheng C., Wei Y., Yurong H., Yulong D., Lingling Z., Chunqing T., Alexei A. L. and Dmitry V. B. (2008). Heat transfer and flow behaviour of aqueous suspensions of titanate nanotubes (nanofluids). Powder Technology Hajar. A and Wei H. P. (2009). Synthesis and flow behaviour of carbon nanotubes nanofluids. Jurnal Teknologi. 51 (F)

7 44 Hong T. K. and Yang H. S. (2005). Nanoparticle-dispersion-dependent thermal conductivity in naofluids. Journal of the Korean Physical Society José R. V. P., José M. O. de Z. and Khayet M. (2008). Measurement of the thermal conductivity of nanofluids by the multicurrent hot-wire method. Journal of Applied Physics Kavitha T., Rajendran A. and Durairajan A (2012). Synthesis, characterization of TiO2 nano powder and water based nanofluids using two step method. European Journal of Applied Engineering and Scientific Research. 1 (4) Keblinski P., Phillput S. R., Chei S. U. S. and Eastman J. A. (2002). Mechanism of heat flow in suspensions of nano-sized particles (nanofluids). International Journal of Heat and Mass Transfer Kim D., Kwon Y., Cho Y., Li C., Cheong S., Hwang Y., Lee J., Hong D. and Leongyong M. (2009). Convective heat transfer characteristics of nanofluids under laminar and turbulent flow conditions. Current Applied Physics Kim J., Kang Y. T. and Choi C. K. (2004). Analysis of convective instability and heat transfer characteristics of nanofluids. Physics of Fluids. 16 (7) Kwak K. and Kim C. (2005). Viscosity and thermal conductivity of copper oxide nanofluid dispersed in ethylene glycol. Korea-Australia Rheology Journal. 17 (2) Kyo S H., Seok D J. and Choi S. U. S. (2009). Flow and convective heat transfer characteristics of water based Al2O3 nanofluids in fully develop laminar flow regime. International Journal of Heat and Mass Transfer

8 45 Li C. H. and Peterson G. P. (2006). Experimental investigation of temperature and volume fraction variations on the effective thermal conductivity of nanoparticle suspensions (nanofluids). Journal of Applied Physics. 99. Madnesh D., Parameshwaran R. and Kalaiselvam. (2014). Experimental investigation on convective heat transfer and rheological characteristics of Cu-TiO2 hybrid nanofluids. Experimental Thermal and Fluid Science Pak B. C. and Cho Y. I. (1998). Hyrdrodynamic and heat transfer study of dispersed fluids with submicron metallic oxide particles. Experimental Heat Transfer. 1(2) Palabiyik I., Witharana S., Musina Z. and Ding Y. (2011). Dispersion stability and thermal conductivity of propylene glycol-based nanofluids. Journal of Nanoparticles Research. 13 (10) Palabiyik I., Witharana S., Musina Z. and Ding Y. (2013). Stability of glycol nanofluids - the consensus between theory and measurement. Powder Technology Paul G., Chopkar M., Manna I. and Das P. K. (2010). Techniques for measuring the thermal conductivity of nanofluids. A review on Renewable and Sustainable Energy Reviews Shriram S. S., Rohit S. K. and Kailas L. (2013). Study on concentric tube heat exchanger heat transfer performance using Al2O3 water based nanofluids. International Communication in Heat and Mass Transfer Singh A. K. (2008). Thermal conductivity of nanofluid. Defence Science Journal. 58 (5)

9 46 Wenzheng C., Minli B., Jizu L., Liang Z., Guojie L. and Miao X. (2012). On the flow chracteristics of nanofluids by experimental approach and molecular dynamics simulation. Experimental Thermal and Fluid Science Xiaohao W., Haitao Z., Tiantian K. and Liqiu W. (2009). Synthesis and thermal conductivity of Cu2O nanoparticles. International Journal of Heat and Mass Transfer Xuan Y. and Li Q. (2003). Investigation on Convective Heat Transfer and Flow Features of Nanofluids. Journal of Heat Transfer. 125 (1) Yang B. and Han Z. H. (2006). Temperature-dependent thermal conductivity of nanorod-based nanofluids. Applied Physics Letters. 89 (8) You S. M., Kim J. H. and Kim K. H. (2003). Effect of nanoparticles on critical heat flux of water in pool boiling heat transfer. Applied Physics Letters Yu W. and Xie H. (2012). A review on naofluids: preparation, stability mechanisms and applications. Journal of Nanomaterials. 17. Zhu D., Li X., Wang N., Wang X., Gao J. and Li H. (2009). Dispersion behavior and thermal conductivity characteristics of Al2O3-H2O nanofluids. Current Applied Physics Zhao C. Y. and Lu T. J. (2002). Analysis of Microchannel Heat Sinks for Electronics Cooling. International Journal of Heat and Mass Transfer Zoubida H., Abid C., Oztop H. F. and Mataoui A. (2014). A review on how the researchers prepare their nanofluids. International Journal of Thermal Sciences