Numerical study on small-scale longitudinal heat conduction in cross-wavy primary surface heat exchanger

The longitudinal heat conduction is usually neglected during the analysis of cross-wavy (CW) primary heat exchanger. In this paper, an anisotropic heat transfer numerical model is proposed to analyze the local thermal field of primary surface plate affected by the small-scale longitudinal heat conduction. Moreover, a detached numerical model is used for simplifying grid and improving computational stability. It shows that the temperature distribution is non-uniform in the anisotropic heat transfer model. The small-scale longitudinal heat conduction makes the temperature distribution of plate become more uniform and enhances the heat exchanger performance. The temperature difference has little effect on the contribution of longitudinal heat conduction, while the contribution of longitudinal heat conduction increases with the increase of the inlet temperature and Reynolds number. •An anisotropic heat transfer model is established to study longitudinal heat conduction (LHC).•A detached numerical model is proposed for analyzing the coupling heat transfer of CW cell.•Small-scale LHC could make temperature distribution of plate uniform and enhance heat transfer.•Effects of inlet temperature, temperature difference and Re on small-scale LHC are studied.