Numerical Investigating the Effect of the Nozzle on the Uniformity of the Refrigerant Distribution of the Evaporator Distributor

Document Type : Article

Authors

1 Department of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran.

2 1Department of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran.

Abstract

In this research, by numerically simulating an evaporator diffuser, the effect of three points on the flow, including nozzle diameter, mixing chamber diameter, and diffuser installation direction, on three uniform performance characteristics, including volume fraction, velocity, and pressure drop inside this refrigeration equipment, was studied. Using ANSYS Fluent software and a two-phase Eulerian model coupled with the VOF model, and considering the continuity and momentum equations, volume fraction of the liquid and vapor phases, and the existence of interphase forces such as drag force, added mass force, and wall lubrication force, and ignoring the heat transfer and mass transfer equations, the simulation was performed in a steady and quasi-transient manner. In the first stage, three diameters of 1.9 mm, 5.7 mm and 20 mm were considered for the nozzle of a diffuser installed in a horizontal position. Then, three diameters of 15.22 mm, 15.28 mm and 15.34 mm were considered for the mixing chamber and finally, three mounting positions of vertical up, vertical down and horizontal were considered for the diffuser.

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Main Subjects


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