The Study Of The Multichannel Solar Chimney Ventilation Pefrormance

As the energy consumption and environmental pollution problems becomeserious, people pay more attention to the use of natural ventilation to achievebuilding energy efficiency and improve the indoor environment. Using the solarenergy to realize natural ventilation in buildings, not only can improve thermalenvironment, satisfy the requirement that the room must be comfortable, butalso can save equipment and running costs, meet the needs of building energyefficiency.Setting a half-cylindrical-heat-wall multichannel solar chimneystructure in the vertical type solar chimney is proposed in this paper andthrough the numerical simulation studying on the ventilation performance of thesolar chimney, aiming to further strengthen the ventilation performance of thesolar chimney. Based on the dimensional numerical simulation, the paperstudied the ventilation performance of multi-channel vertical type solar chimneyoptimization structure in different channel width W,half cylindrical heatabsorption wall in different radius R under the coupled action of thermalpressure and wind hot pressing, gained the local velocity field,the temperaturefield and the ventilation rate inside the multichannel solar chimney, finally,carried on the detailed analysis. The results show that:When only considering thermal effect, within the scope of the heat fluxdensity of100W/m2~1000W/m2, the ventilation rate of the multichannel solarchimney increases along with the increase of the width of the chimney, but the magnitude of the air volume growth becomes smaller and smaller; Under thecertain solar chimney structure size, the ventilation rate inside the chimneyincreases as the increase of the heat flux density.When only has the thermal effect, All the ventilation rate of themultichannel solar chimney higher than the ventilation rate of the traditionalmultichannel solar chimney,its ventilation rate increases as the increase of thechimney channel width is greater than the increase of the traditional one, whenthe radius of chimney is150mm, the growth of the natural ventilation ratereaches38.9%,but the growth of the traditional one can just mostreaches25%,when the width is certain, the growth on the ventilation rate of themultichannel solar chimney divides the biggest growth of the traditional one isabout36.4%; when the heat flux density is certain,the ventilation rate of themultichannel solar chimney is higher than the ventilation rate of the traditionalmultichannel solar chimney.In the hot pressing and under the joint action of wind pressure, theventilation rate of the traditional multichannel solar chimney increases as theincrease of the heat flux density and the outdoor wind speed, the outdoor windfield has induced effects on the ventilation rate inside the solar chimney, andprompt the increase of the heat flux density inside the chimney, within the scopeof the paper studied, wind pressure and hot pressing role mutual gain. For thecertain structure size of the multichannel solar chimney, in the heat flux densityof100W/m2~1000W/m2, the outdoor wind speed is within the scopeof0.5m/s~4.0m/s, as the increase of the outdoor wind speed, the ventilation rateof the multichannel solar chimney increases constantly, the wind pressure havereinforcements in the ventilation performance of the solar chimney.