Measuring of thermal characteristics for Peltier thermopile using calorimetric method

摘要

In this article there is presented a technique of calorimetric measurement for Peltier thermopile (PT) characteristics with minimum requirements concerning the measuring equipment (calorimetric tank, temperature sensors, multimeters, PC). In order to obtain relations among a temperature difference, an electric current and a total cooling power output there was a set of measurements performed. According to the measurements it was able to achieve the temperature characteristics of the cooling power output and to evaluate the coefficient of performance (COP) during a cooling process. The measuring process is fully automated. And it uses a spontaneous increase of a temperature difference between PT plates and a regulator keeping a constant temperature of a hot side in the cooling device. An analysis of the calorimetric vessel thermal resistance in dependence on the temperature boundary conditions is very important for an insulation of a heat transfer media. In this paper there is this analysis performed analytically using a numerical simulation by means of the software product ANSYS CFX and the obtained results are compared with the experimental data. The measured thermal characteristics consist of a dependence of the cooling power output and the COP on the temperature differences at the constant temperature level 333.15 K of the hot plate and at the electric current values 2 A, 4 A and 6 A. The proposed measuring method, as well as the results published in this article, can be utilized for a design optimisation of equipment with the installed PT, which serves as a cooling element. An application of the calorimetric approach for measuring of characteristics is also suitable for a cascade interconnection of the PT, where it is necessary to set up the supply electric currents correctly in order to reach the maximum COP.