A Study Of Thermal Performance And Load Characteristic For Exfiltration Thermal Insulation

Building energy efficiency is one of the key elements in sustainable development, interms of achieving low energy consumption, improving indoor thermal and visualcondition, and keeping essential sanitary condition. The research and development ofbuilding energy efficiency are consisted of four main parts, including developing highthermal performance building envelope for reducing thermal load, decreasing energyconsumption with high efficient devices, using appropriate control strategy and device tokeep efficient operation and comfort indoor condition, and applying renewable energy forreducing Greenhouse gas emission.A novel building envelope, which is called exfiltration thermal insulation, wasproposed. This structure combines load bearing of building and permeability of porousmaterial. By transferring conduction heat gains to the flowing air in the porous materialand discharging it to the outside, the air reverse insulation wall can significantly improvethermal performance. The reduction of radiant heat exchange between the occupant andindoor surface of wall can effectively improve thermal comfort without. Exfiltrationthermal insulation can achieve building energy efficiency and conservation.The modes of operation and numerical heat transfer model have been carried out interms of steady and unsteady condition. The issues which affect the thermal performanceof wall have been analyzed. Besides that, the comparison of conventional walls andexfiltration thermal insulation, in terms of thermal insulation properties, decrement factors,and time-delay, have been developed in cooling season. The difference of thermalresponse, cooling load and thermal comfort between conventional walls and exfiltrationthermal insulation has been discussed. Moreover, the integration of indoor air energyconservation and heat transfer in building envelope has been developed for analyzing theperformance of various building envelope in terms of indoor thermal response, thermalload and thermal comfort in summer.The results indicate that the permeated airflow rate and the thickness of porousmaterial have a great impact on heat transfer of exfiltration thermal insulation. When airvelocity and thickness of porous material increase, the thermal insulation properties will be improved. Compared with convectional walls, exfiltration thermal insulation providebetter thermal performance, and decrement factors may approach zero. Energy Byapplying the exfiltration thermal insulation, thus thermal response, cooling load, andthermal comfort will be enhanced.Based on the above study, exfiltration thermal insulation can achieve better thermalperformance than other walls and have a great potential in commercial application.Meanwhile the results can provide better understanding of research methods, study, designand application of building energy saving.