Thermal performance analysis of a double-channel phase change slurry Trombe wall with seasonal switching, solar energy storage and utilization

A novel double-channel Direct absorption solar collector based on Phase change slurry - Trombe Wall (DPTW) was proposed with heating and shading modes for winter and summer. Combined with Phase change material - TW (PCMTW) and traditional TW, the effect of double-channel DPTW on thermal environment and energy consumption was evaluated. Results showed that in winter, the monthly average indoor temperature of DPTW, PCMTW and TW was 18.7, 18.2 and 18.3 °C. DPTW increased the duration of indoor temperature within 18.5–25.5 °C to 21.4 %, nearly twice that of the other two systems. In summer, DPTW decreased the duration of indoor temperature above 26.0 °C to 5.1 %, while the duration of other systems exceeded 10.0 %. Compared to PCMTW and TW, DPTW reduced heating energy consumption by 8.2 % and 3.2 %, as well as reduced cooling energy consumption by 10.6 % and 15.8 %. Three key parameters of phase change slurry (PCS) were optimized, including phase change temperature , volume fraction, and thermal conductivity . Based on optimized PCS, heating and cooling energy consumption of DPTW was further decreased by 18.5 % and 9.4 %. Double-channel DPTW system demonstrated exceptional climate adaptability, with the maximum energy saving rate at 67.1 % and 30.5 % in winter and summer of six cities.