论文部分内容阅读
在抛物镜、透镜或定日镜群的聚焦面上可获得很高的温度。虽然决定温度高低的因素很多,但最重要的是聚光比。聚光比定义为抛物镜的开口面积或定目镜群的总面积与它们焦平面上光斑面积之比,它是设计聚光型太阳能利用装置最重要的参数之一。聚光比越大,光斑的温度就越高。那么聚光比有没有极限值呢?如果有,它是多大?我们在回答这个问题之前,首先作两个极端的假定: (1) 聚光装置位于地球的大气层外,因而可以不考虑对流和传导热损。 (2) 聚光装置是理想的,它的镜面反射系数为1(如是透镜,它的透过系数为1),它能将接受到的太
High temperatures can be achieved on the focusing surfaces of parabolic, lens or heliostat clusters. Although many factors determine the temperature level, but the most important thing is the concentration ratio. Concentration ratio is defined as the ratio of the opening area of the parabolic lens or the total area of the lens group to the area of the spot on their focal plane. It is one of the most important parameters in the design of a concentrating solar energy utilization device. The higher the spot ratio, the higher the spot temperature. So, if there is, what is it? Before we answer this question, we first make two extreme assumptions: (1) The condensing device is located outside the Earth’s atmosphere and therefore can not consider convection and Conduction heat loss. (2) A condenser is ideal, with a specular reflection coefficient of 1 (ie, a lens with a transmission factor of 1) that will accept received