Thermal performance measurement device and thermal performance prediction method of parabolic trough solar collector

Abstract

The invention provides a measurement device of thermal performance of a paraboloid groove type solar thermal collector and a thermal performance prediction method. A measurement device subsystem is installed on a heat transferring fluid circulation subsystem or near the heat transferring fluid circulation subsystem. A nitrogen sealing subsystem is connected with the top of a heat exchanger (9) in the heat transferring fluid circulation subsystem. A cooling circulation subsystem is connected with an inlet-outlet of a cooling medium side of the heat exchanger (9) in the heat transferring fluid circulation subsystem. According to the invention, by continuously measuring the heat transferring fluid inlet-outlet temperature, the size flows, the solar normal perpendicular incidence irradiancy, the environmental air temperature and the environmental air speed in a temperature rise process and a temperature descending process of the heat transferring inlet-outlet, through a dynamic prediction model of the thermal performance of the paraboloid groove type solar thermal collector, by adopting a multivariate linear regression mathematic method based on the least square class method, seven undetermined parameters are identified, and the thermal performance of the paraboloid groove type solar thermal collector under any one specific working condition like time, a place, solar irradiation, environmental air temperature and temperature of the heat transferring fluid inlet is predicted.

Description

technical field [0001] The invention relates to a thermal performance dynamic measurement device and a thermal performance prediction method of a parabolic trough solar heat collector. Background technique [0002] The parabolic trough solar collector is mainly used in solar thermal power stations. It uses the parabolic trough concentrator to perform a one-dimensional rotational motion around the heat absorbing tube located at the focal line of the trough to track the sun, so that the converging direct solar radiation heats the absorber. The heat pipe, and then the heat is taken out by the heat transfer fluid flowing through the heat absorbing pipe, so as to realize the conversion of solar energy into heat energy. The most important evaluation and acceptance index of parabolic trough solar collector application technology is the thermal performance of the collector. At present, it is considered to be the most reliable and accurate method to predict the thermal performance o...

AI Technical Summary

Problems solved by technology

However, the specific functional expression of the incident angle correction factor provided by this standard is only applicable to flat-plate solar collectors, not to parabolic trough solar collectors

Moreover, this standard only considers the measurement of the temperature rise process of the collector, and requires that the inlet temperature of the heat transfer fluid of the collector is stable at ±1°C during the measurement process

The standard's consideration of solar diffuse irradiance instead brings uncertainty to the thermal performance prediction of trough collectors with high concentration ratios

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