The performance analysis of a high-efficiency dual-channel Trombe wall in winter

In order to improve the thermal efficiency of Trombe wall in winter conditions, a novel system of high-efficiency dual-channel Trombe wall was proposed in this paper. The influence of different baffle shapes (that is corrugated C-shaped baffle and flat baffle) and their location on the thermal performance of the novel system were studied experimentally. In addition, the mathematical model of the dual-channel Trombe wall system was established and validated. The optimal configuration and position of the insulation baffle were discussed by simulation. Experimental results showed that the heating effect was the best when the total channel thickness was 0.5 m, and the baffle was 0.2 m apart from the glass cover. For dual-channel Trombe wall with corrugated C-shaped baffle, the temperature difference between the inlet and outlet, the indoor air temperature, the maximum thermal efficiency, and the maximum volume flow rate were 8.1 °C, 21.7 °C, 58.1%, and 240.9 m³/h, respectively, which were 4.9 °C, 5.6 °C, 5.1 times, and 98% higher than that of the traditional Trombe wall. Similar conclusions can be obtained for dual-channel Trombe wall with flat baffle, which was also superior to traditional Trombe wall. The simulation results indicated that the thermal efficiency would be optimal when the thickness ratio of outer air channel to total air channel was 0.3–0.4, 0.4 to 0.5 for dual-channel Trombe wall with corrugated C-shaped baffle and flat baffle, respectively. Furthermore, both the ambient temperature and solar radiation intensity had positive effect on thermal efficiency. The results could provide beneficial effect on the development of the improved Trombe wall.