| Title |
Theoretical Analysis of a Rotary Heat Exchanger Based on a Simplified Model |
| Authors |
Sung Gyun Son ; Yongchan Kim ; Dae-Young Lee |
| DOI |
http://dx.doi.org/10.6110/KJACR.2015.27.8.409 |
| Keywords |
회전형 열교환기 ; 이론해석 ; 유용도 ; 열용량 ; 열확산계수 Rotary heat exchanger ; Theoretical analysis ; Effectiveness ; Thermal capacity ; Thermal diffusivity |
| Abstract |
A simplified rotary heat-exchanger model was developed with an assumption of a linear temperature distribution along the flow direction. Based on the model, the exact fluid solution and solid temperature variations were obtained and verified from a comparison with previous numerical studies. The heat transfer in the rotary heat exchanger was investigated using the theoretical solutions. The heat exchanger’s effectiveness was shown to be saturated, with a rotational-speed increase that is higher than a critical value that is solely dependent on the thermal capacity of the solid matrix but independent of the fluid flow rate; the saturated value of the effectiveness was determined only by the NTU of the heat exchanger. Where the thermal diffusivity of the solid matrix is so slight that the thermal penetration depth becomes smaller than the matrix thickness, the effective thermal capacity of the solid matrix decreased according to the penetration depth. |