The aim of this study is the numerical analysis of the melting process of the phase change material(PCM)in a spiral coil.The space between the inner tube and outer shell is filled with RT-50 as PCM.Moreover,the hybrid...The aim of this study is the numerical analysis of the melting process of the phase change material(PCM)in a spiral coil.The space between the inner tube and outer shell is filled with RT-50 as PCM.Moreover,the hybrid nanofluid(with a carbon component)flows through the inner tube.The novelty of this work is to use different configurations of fin and different percentage of hybrid nanoparticles(SWCNTs-Cu O)on the PCM melting process.In the numerical model created by ANSYS-Fluent,the effect of various inlet temperatures is investigated.The results indicate that the extended surface created by extra fin has a dominant effect on melting time,so by adding the third fin,the melting time is reduced by 39.24%.The next most influential factor in PCM melting is the inlet temperature of the working fluid,so that 10°C increment of temperature result in the PCM melting time decreased by 35.41%.展开更多
In this paper,in order to improve the performance of a linear parabolic collector,the thermal effects of using Al_(2)O_(3)-syltherm oil nanofluid with different concentrations and new flange-shaped turbulators are inv...In this paper,in order to improve the performance of a linear parabolic collector,the thermal effects of using Al_(2)O_(3)-syltherm oil nanofluid with different concentrations and new flange-shaped turbulators are investigated.The simulation was performed by ANSYS-FLUENT-18.2 commercial software using Realizable k-εtwo-equation turbulence model.In accordance with the results,it was realized that increasing the volume fraction of nanoparticles(to 5%)and number of turbulators causes the heat transfer coefficient(h)of the fluid to elevate and ultimately the uniform temperature is created in the absorber.For instance,at a flow rate of 4.5kg/s and an inlet temperature of 350 K,the value of h increases by about 8.5%by changing the number of turbulators from 10 to 15 sets.On the other hand,the results indicate that by changing the arrangement of the turbulators,the heat transfer efficiency of the collector can be increased by 5%for 350 K,3.5%for 450 K and 1%for 550 K inlet temperature.展开更多
文摘The aim of this study is the numerical analysis of the melting process of the phase change material(PCM)in a spiral coil.The space between the inner tube and outer shell is filled with RT-50 as PCM.Moreover,the hybrid nanofluid(with a carbon component)flows through the inner tube.The novelty of this work is to use different configurations of fin and different percentage of hybrid nanoparticles(SWCNTs-Cu O)on the PCM melting process.In the numerical model created by ANSYS-Fluent,the effect of various inlet temperatures is investigated.The results indicate that the extended surface created by extra fin has a dominant effect on melting time,so by adding the third fin,the melting time is reduced by 39.24%.The next most influential factor in PCM melting is the inlet temperature of the working fluid,so that 10°C increment of temperature result in the PCM melting time decreased by 35.41%.
文摘In this paper,in order to improve the performance of a linear parabolic collector,the thermal effects of using Al_(2)O_(3)-syltherm oil nanofluid with different concentrations and new flange-shaped turbulators are investigated.The simulation was performed by ANSYS-FLUENT-18.2 commercial software using Realizable k-εtwo-equation turbulence model.In accordance with the results,it was realized that increasing the volume fraction of nanoparticles(to 5%)and number of turbulators causes the heat transfer coefficient(h)of the fluid to elevate and ultimately the uniform temperature is created in the absorber.For instance,at a flow rate of 4.5kg/s and an inlet temperature of 350 K,the value of h increases by about 8.5%by changing the number of turbulators from 10 to 15 sets.On the other hand,the results indicate that by changing the arrangement of the turbulators,the heat transfer efficiency of the collector can be increased by 5%for 350 K,3.5%for 450 K and 1%for 550 K inlet temperature.