Simulation on the inner flow field of a horizontal tubes of falling film evaporator in a refrigeration system was performed using two-phase flow model VOF in FLUENT
and the influence of different tube arrangements on the flow field was examined. The results show that the large vapor velocity and the non-uniform flow field inside the evaporator affect the distribution of liquid droplets significantly because of the small refrigerant liquid velocity. When the velocity of the refrigerant flowing into the evaporator is small
it seems more suitable to adopt the tube arrangement with horizontal vapor passages. It is likely that the tube arrangement with smaller space in the upper portion and larger space in the lower portion is more reasonable because of the large proportion of the vapor from flooded refrigerant inside the bottom of the evaporator.
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