透明盖板与外界空气间的对流换热系数,盖板热阻之比,吸热板与盖板间自然对流因子,计算太阳能集热器的出口温度和瞬时效率-Convective heat transfer coefficient between the outside air and the transparent cover, the cover ratio of the thermal resistance between the absorber plate and cover natural convection factor