PHE-22 CFD Simulations of a Plate-and-shell Heat Exchanger

K. J. Farrell

HTRI experimentally evaluated the thermal-hydraulic performance of a water-water plate-and-shell heat exchanger at the Research & Technology Center and then used the results to calibrate a solution approach through computational fluid dynamics. The tortuous flow paths through the corrugated channels of the plate pack were modeled effectively using porous media. Inertial resistance coefficients were based on HTRI plate friction factor relations that vary with Reynolds number, chevron angle, mass velocity, fluid properties, effective (hydraulic) diameter, and a wall correction. In similar fashion, we calculated a heat transfer coefficient for each corrugated channel using an analogous j-factor relation and normalized it by the coefficient for a smooth, parallel plate channel using the Dittus-Boelter relation. We applied this multiplier to the heat transfer coefficient for each of the 79 plain, smooth, parallel channels in the CFD model. The simulation results reiterate the high thermal effectiveness of this exchanger type from Vahterus Oy and reveal minimal channel-by-channel flow variation. Plateside port pressure losses are consistent with current correlations. Shellside port pressure losses are predicted reasonably well using a summation of minor losses derived from canonical correlations. The computational approach is well suited to studying the effect of port configuration and channel count on flow distribution and hydraulic losses.