Fig. 1. Single channel simplified model of PCHE

Fig. 2. Diagram of the model structure (a) Channel cross-section, (b) The arrangement of airfoil fins

Fig. 3. Structure diagram of the airfoil fins

Fig. 4. Grid independence analysis

Fig. 5. Comparison of simulation and experimental data

Fig. 6. Effect of inlet temperature on Nu

Fig. 7. Effect of inlet temperature on f

Fig. 8. Velocity contours of channel cross-section

Fig. 9. Pressure contours of channel cross-section

Fig. 10. Turbulent kinetic energy contours of channel cross-section

Fig. 11. Nuvs. Re with different fin types

Fig. 12. fvs. Re with different fin types

Fig. 13. Velocity contours of channel cross-section

Fig. 14. Pressure contours of channel cross-section

Fig. 15. Turbulent kinetic energy contours of channel cross-section

Fig. 16. Nuvs. Re with different fin pitchs

Fig. 17. fvs. Re with different fin pitchs

Fig. 18. Comparison of various airfoil fin structure channels and straight channels

Fig. 19. Comparison of Nu between the CFD results and empirical formula calculation

Fig. 20. Comparison of f between the CFD results and empirical formula calculation