Numerical investigation of effect of fill ratio and inclination angle on a thermosiphon heat pipe thermal performance

Abstract Computational Fluid Dynamic (CFD) modelling of a heat pipe is a powerful tool that can be used to investigate the complex physical phenomena of the evaporation and condensation phase change processes inside thermosiphon heat pipes. In this work, a new CFD simulation of two phase flow inside thermosiphon heat pipe is carried out to investigate the effect of fill ratio (ratio of liquid volume to the evaporator volume) and inclination angle on its thermal performance in terms of temperature distribution and thermal resistance using FLUENT (ANSYS 15). Results of the CFD simulation were compared to published experimental data showing good agreement with maximum deviation of 4.2% and 8.1% for temperature distribution and thermal resistance, respectively. In addition, numerical results of inclination angle were also compared with experimental data in terms of thermal resistance giving maximum deviation of 1.3%. Using the validated CFD modelling, results showed that at low fill ratio and low inclination angle, there was a significant increase in the evaporator temperature. Regarding the thermal resistance, a fill ratio of 65% and inclination angle of 90° produced the lowest thermal resistance for all the heat input values used. Also, as heat input increases, the effect of the fill ratio and inclination angle becomes more significant.

[1]  T. Yousefi,et al.  Experimental study on the effects of inclination situation of the sintered heat pipe on its thermal performance , 2015 .

[2]  Masoud Rahimi,et al.  CFD modeling of flow and heat transfer in a thermosyphon , 2010 .

[3]  David Reay,et al.  Heat pipes : theory, design and applications , 2014 .

[4]  Krishna D.P. Nigam,et al.  CFD modeling of flow profiles and interfacial phenomena in two-phase flow in pipes , 2006 .

[5]  Angel Huminic,et al.  Numerical study on heat transfer characteristics of thermosyphon heat pipes using nanofluids , 2013 .

[6]  Bala Abdullahi,et al.  Development and optimization of heat pipe based compound parabolic collector , 2015 .

[7]  K. Palaniradja,et al.  An Investigation of Thermal Performance of Heat Pipe Using Di-water , 2012 .

[8]  Hussam Jouhara,et al.  CFD modelling of a two-phase closed thermosyphon charged with R134a and R404a , 2015 .

[9]  S. H. Noie.  Heat transfer characteristics of a two-phase closed thermosyphon , 2005 .

[10]  B. Sivaraman,et al.  Effect of Inclination Angle in Heat Pipe Performance Using Copper Nanofluid , 2012 .

[11]  Zhen Yang,et al.  Numerical and experimental investigation of two phase flow during boiling in a coiled tube , 2008 .

[12]  M. Rosen,et al.  Experimental investigation of the effect of graphene nanofluids on heat pipe thermal performance , 2016 .

[13]  Thanaphol Sukchana,et al.  Effect of Filling Ratios and Adiabatic Length on Thermal Efficiency of Long Heat Pipe Filled with R-134a , 2013 .

[14]  J. Brackbill,et al.  A continuum method for modeling surface tension , 1992 .

[15]  Rouhollah Ahmadi,et al.  Influence of surface wettability on bubble behavior and void evolution in subcooled flow boiling , 2015 .

[16]  Hasna Louahlia-Gualous,et al.  Experimental investigation of thermosyphon loop thermal performance , 2014 .

[17]  A. F. Akon,et al.  PERFORMANCE OF HEAT PIPE FOR DIFFERENT WORKING FLUIDS AND FILL RATIOS , 2011 .

[18]  Geraldine J. Heynderickx,et al.  Modeling the evaporation of a hydrocarbon feedstock in the convection section of a steam cracker , 2009, Comput. Chem. Eng..

[19]  A. Shooshtari,et al.  Volume of fluid-based numerical modeling of condensation heat transfer and fluid flow characteristics in microchannels , 2013 .

[20]  Yuwen Zhang,et al.  Effects of mass transfer time relaxation parameters on condensation in a thermosyphon , 2015, Journal of Mechanical Science and Technology.

[21]  Hussam Jouhara,et al.  Numerical modelling of the temperature distribution in a two-phase closed thermosyphon , 2013 .

[22]  Guy Marin,et al.  CFD modeling of all gas–liquid and vapor–liquid flow regimes predicted by the Baker chart , 2008 .

[23]  Kenneth E. Goodson,et al.  VOLUME OF FLUID SIMULATION OF BOILING TWO-PHASE FLOW IN A VAPOR-VENTING MICROCHANNEL , 2010 .

[24]  W. Qu,et al.  Experimental study on effect of inclination angles to ammonia pulsating heat pipe , 2014 .

[25]  Amir Faghri,et al.  Heat Pipe Science And Technology , 1995 .

[26]  Rahmatollah Khodabandeh,et al.  Thermal performance of inclined screen mesh heat pipes using silver nanofluids , 2015 .

[27]  Limin Qiu,et al.  Investigation on the effect of filling ratio on the steady-state heat transfer performance of a vertical two-phase closed thermosyphon , 2008 .

[28]  Anthony J. Robinson,et al.  Experimental investigation of small diameter two-phase closed thermosyphons charged with water, FC-84, FC-77 and FC-3283 , 2010 .