太阳能热水器热辐射流对管内水流引起的温升分布

假定太阳能热水器中管内水流速度不大且在管内作分层稳定流动，太阳热辐射流通过管内壁垂直输入水柱侧面，控制水流速度，水柱在管内输运过程有足够时间吸收热辐射流而逐渐升温，使管内的出端水温高于进端水温．由此建立管内水流的热传导方程，考虑第一、第二类边界条件，在圆柱坐标系中求解，并利用变数分离法和贝塞尔函数的性质，导出了热水器中管内水温的分布

Distribution of temperature rise of water current caused by heat radiation current which transmits in water current in pipe of solar heater

he paper assumes:The velocity of water current in pipe of solar heater is not fast;the flowing of the water corrent in the pipe is stratified and stationary.If heat radiation current goes htrough inner wall of hte pipe and directs at the side face of water column in the pipe perpendicularly and the welocity of water current is controlled ,then the water has enough time to absorb thermal radiation current and its temperature rises gradually during the course of its transmissionin in the pipe.The temperature of exit is higher than that of entrance.According to the equation of heat conduction and the first and the first and the second sorts of boundary conditions,the paper gives solutions of the fised conditions.Under the conditions of using cylinder coordinate system,method of variable number separation and property of Bessel function,the paper deduces the distribution of water temperature in pipe of solar heater.