Numerical Investigation of Flow Field and Heat Transfer in Cross-Corrugated Ducts

Regenerative and recuperative plate heat exchangers consist of ten of stacked corrugated plates. The orientation of the corrugation between neighboring plates is nonaligned. Multitude contact points between the plates lead to high compressive strength of the heat exchangers. The corrugations give structural stability even at low material thickness of the plates and produce highly complex flow structure which determines the thermal performance and the flow loss of the heat exchanger. Here, flow field and heat transfer in sine-wave crossed-corrugated ducts have been investigated by numerical solution of the Navier-Stokes and energy equations in the laminar and transitional flow regime between Re = 170 and 2000. The ratio of the corrugation wave length {lambda}{sup *} to amplitude a{sup *} has been varied between 7 and 10. The angle of the corrugation of the neighboring plates has been kept fixed at 45 deg. Results show that the critical Reynolds number for self-sustained flow oscillations is about 240. For Reynolds numbers larger than 1000, the Nusselt number and the friction factor are nearly independent of the dimensionless wavelength. Computational results compare well with available experimental results.