CFD CODE APPLICATION TO FLOW THROUGH NARROW CHANNELS WITH CORRUGATED WALLS

Novel compact condensers and in general two-phase heat exchangers made of corrugated plates hold significant advantages over conventional equipment. In an effort to optimise design and operation of this type of equipment, a commercial CFD code (CFX  ) is employed to simulate the flow through an element of a model compact heat exchanger and to provide information on the local flow structure. For simplicity, the channel used for the simulation is formed by only one corrugated plate, which is comprised of twelve equal sized and uniformly spaced corrugations and two side-grooves, while the other plate is flat. The Reynolds numbers examined are 290, 850, 1150 and 1450. A standard k-e model was used for the calculations and, in addition to isothermal flow, heat transfer simulations are carried out for the case of hot air (60 o C) in contact with a constant-temperature wall (20 o C). Results are presented in terms of velocity, temperature, wall shear stress, wall heat flux and local Nusselt number profiles. The results confirm the dominant role of the vertical sidegrooves in flow distribution. These calculated mean heat transfer coefficients are found to be in reasonable agreement with the limited published experimental data.