An investigation of heat transfer coefficient during refrigerants condensation in vertical pipe minichannels

An experimental investigation of heat transfer of Fe2O3/Water nanofluid in a double pipe heat exchanger

One way to increase the heat transfer is to use perforated twisted tapes with different hole diameters, which largely improve heat transfer with an increase in the heat transfer area at the constant volume and more mixed flow. In the previous studies, the effect of nanofluids with perforated twisted tapes is less studied. In this work, the performance of water / iron oxide nanofluid in a double...

An experimental investigation of heat transfer of Fe2O3/Water nanofluid in a double pipe heat exchanger

One way to increase the heat transfer is to use perforated twisted tapes with different hole diameters, which largely improve heat transfer with an increase in the heat transfer area at the constant volume and more mixed flow. In the previous studies, the effect of nanofluids with perforated twisted tapes is less studied. In this work, the performance of water / iron oxide nanofluid in a double...

Condensation Heat Transfer of Pure Refrigerants in Microfin Tubes

Evaporation and Condensation Heat Transfer Performance of Flammable Refrigerants in a Brazed Plate Heat Exchanger

Average Nusselt numbers were measured for R22, R290, R290/600a, and R32/152a undergoing evaporation and condensation in a brazed plate heat exchanger. The refrigerants experienced wavy, stratified flow at low heat and mass fluxes, 1.3 kW/m2 to 8.3 kW/m2 and 1.6 kg/m2 s to 19 kg/m 2 s, respectively. Heat transfer correlations from the literature for in-tube and channel flow of refrigerants with ...

Factor Effect Estimation in the Convective Heat Transfer Coefficient Enhancement of Al2O3/EG Nanofluid in a Double-pipe Heat Exchanger

The forced convective heat transfer (CHT) coefficient of a particular nanofluid, Al2O3 nanoparticles-ethylene glycol (EG) mixture, was investigated experimentally in a double-pipe heat exchanger. The nanofluid Nusselt number for different nanoparticles’ concentrations as well as various operating temperatures was measured to be increased up to 23.7% using 1.0% wt of nanoparticles. The significa...