Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5017142 | International Journal of Refrigeration | 2017 | 28 Pages |
Abstract
An experimental study was conducted on a 19.05âmm (outer diameter) dimpled enhanced tube to evaluate the in-tube two phase heat transfer and pressure drop performance in an annular section created between the enhanced tube and a solid round PVC rod. The purpose of the study was to understand the effect of forced early transition to annular flow on the pressure drop and heat transfer coefficient in a horizontal tube. The refrigerant studied was R-134a at a saturation temperature of 5â°C, heat flux range 2.5 to 15âkW mâ2, mass flux from 80 to 200âkgâmâ2âsâ1 and inlet vapor quality of 0.12 to 0.72. Flow pattern and pressure drop results were obtained under adiabatic conditions. Under similar operating conditions the enhanced tube with a rod exhibited three times higher heat transfer performance versus same size smooth empty tube with lower pressure drop penalty at lower mas flux.
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Physical Sciences and Engineering
Engineering
Mechanical Engineering
Authors
Zahid H. Ayub, Adnan H. Ayub, Gherhardt Ribatski, Tiago Augusto Moreira, Tariq S. Khan,