Optical efficiency measurement device and test method of trough solar collector tube

Abstract

A device for measuring the optical efficiency of a trough-type solar heat collecting tube and a testing method thereof, including an elliptical concentrator, an elliptical concentrator support, a sun simulation light source, a trough-type solar heat collecting tube support, a first temperature equalizing device, a second Equalization device, spoiler rod, flow meter, fluid driven pump, liquid supply tank, liquid storage tank and measurement system. The elliptical concentrator is a chamber with a non-complete ellipse in cross section. The inner wall of the elliptical concentrator has a mirror surface. on the focal line. The elliptical concentrator reflects and focuses the light emitted by the sun simulation light source onto the trough solar heat collecting tube. The two ends of the trough-type solar collector tube to be tested and the interior are respectively placed with a temperature equalization device and a spoiler rod. By comparing the actual heat gain of the trough-type solar collector tube to be tested with the heat gain of the standard trough-type solar collector tube, the to-be-tested trough-type solar collector tube is obtained. Measuring the optical efficiency of trough solar collector tubes.

Description

technical field [0001] The invention relates to the field of solar thermal utilization, in particular to a device for measuring optical efficiency of a trough-type solar heat collecting tube and a testing method thereof. Background technique [0002] Trough solar thermal power generation is currently the most widely used and lowest-cost solar thermal power generation technology in the world. It uses parabolic reflectors to reflect and focus sunlight to the trough solar collector tube located on its focal line to heat the fluid in the tube, and then Generate high-temperature steam to drive the steam turbine to generate electricity. The trough-type solar heat collector is the most critical component in the solar thermal power generation system from light to heat, and its optical efficiency directly affects the power generation efficiency and operating cost of the solar power station. The optical efficiency of the trough solar collector tube is one of the core performance indi...

AI Technical Summary

Problems solved by technology

At present, the optical efficiency measurement of trough solar collector tubes is mostly through actual field tests. This optical efficiency measurement method is subject to the instability and intermittent (cloudy weather) of solar radiation, wind speed changes and rainy factors, resulting in large test errors. The test period is long, etc., resulting in the difficulty of measuring the optical efficiency of the trough solar collector tube and the test error is very large

[0004] Invention patent 201410026437.2 proposes to use an elliptical closed chamber to measure the optical efficiency of the medium-high temperature solar heat collector tube. In the specific test, on the one hand, when the elliptical closed chamber is used for the test, the entire circumferential direction of the trough solar heat collector tube is There is concentrated light, which is inconsistent with the actual trough solar thermal power generation system, resulting in insufficient test accuracy

On the other hand, due to the long length of the medium-high temperature heat collecting tube, it is very difficult to place it into the elliptical closed chamber, and the elliptical closed chamber is also difficult to operate, which makes the actual use more difficult and is easy to cause damage to the inner surface of the elliptical concentrator , especially the air temperature in the closed chamber is accumulating over time, so there must be a ventilation device, but the air in the chamber changes greatly, which has a great impact on the test accuracy

In addition, in this invention patent, no temperature equalization device is used, the test stability of the inlet and outlet temperature is poor, and the accuracy is low, especially because the temperature rise of the inlet and outlet of a single heat collecting tube is only about 2-7°C, the accuracy of the inlet and outlet temperature test is seriously affected Test Results

At the same time, there is no spoiler rod in the heat collecting tube during the test, the fluid distribution in the tube is uneven, the flow rate is low, the heat transfer performance is poor, and the heat collecting tube often bends and cracks due to uneven temperature distribution.

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