自然通风型光伏双层皮幕墙光热传递特性研究

Study on the Photovoltaic Transfer Characteristics of Naturally Ventilated Photovoltaic Double-skin Facade

搭建了自然通风型光伏双层皮幕墙全尺寸实验房,采用了4种自然通风循环模式,分别对外层皮透过率为100%及20%的双层皮幕墙热工参数进行实验测量。结果表明,4种自然通风循环模式的光伏双层皮幕墙结构均能够起到有效阻隔室外热量传递,并具备发电功能。透过率20%的光伏双层皮幕墙内外玻璃温差10℃以上,太阳得热系数0.1以下,U值2 W/(m^(2)·K)左右;透过率100%的光伏双层皮幕墙内外玻璃温差5℃以下,太阳得热系数0.15以上,U值2.5 W/(m^(2)·K)左右。外循环模式更好的带走空腔内热量,在降低室内得热方面为最优;贯穿型只加强了自然通风,不能有效的带走空腔内的热量;内外循环模式能够将室内热量带出室外,相比外循环模式可以形成由内到外的通风形式;内循环模式将空腔内的热量带入室内,形成了空调负荷,为不利的循环模式。本研究为自然通风型光伏双层皮幕墙在建筑光伏一体化中应用提供依据。

A full scale experimental room of the natural ventilation type PV double-skin curtain wall was built.Four natural ventilation circulation modes were used to measure the thermal parameters of the double-skin curtain wall with 100% and 20% transmissivity of the outer skin respectively.The results show that the photovoltaic double-skin facade with four natural ventilation circulation modes can effectively block the heat transfer outside and generate electricity.The temperature difference between the inner and outer glass of PV double-skin facade with 20% transmissivity is higher than 10℃,with solar heat gain coefficient less than 0.1,and the U value of about 2 W/(m^(2)·K).The solar heat gain coefficient is higher than 0.15 and the U value is about 2.5 W/(m^(2)·K)with the glass temperature difference between inner and outer of the photovoltaic double-skin facade less than 5℃ with 100% transmissivity.The external circulation mode takes the heat away from the cavity better,which is the best way to reduce the heat gain in the room.The through circulation mode only strengthens the natural ventilation and cannot take the heat away from the cavity effectively.Compared with the external circulation mode,the internal and external circulation mode can form the inside-to-outside ventilation form.The internal circulation mode brings the heat from the cavity into the room,which forms the air conditioning load and is an unfavorable circulation mode.This study provides the basis for the application of natural ventilation type PV double-skin curtain wall in buildingintegrated photovoltaics.