High-precision calibration device and method for thin film type heat flow meter

Abstract

The invention discloses a high-precision calibration device and method for a thin film type heat flow meter. A direct-current constant-voltage power supply in a heating system ensures that polyimide electric heating films output stable heating power; constant-temperature water cavities in a cooling system are connected with a temperature-adjustable cooling water circulating machine by pipes to ensure a constant cooling temperature; a Keithley multichannel data collector in a data acquisition system realizes thermoelectric signal conversion, and computer software records and stores temperatureand potential data. In the calibration device, the polyimide film is hollowed according to the shape of the heat flow meter to reduce the contact surface air gap and the contact thermal resistance; flexible regulation and control of the working temperature of to-be-calibrated heat flow meters are achieved by adjusting the heating power and cooling circulating water temperature and arranging mica sheets, high-heat-conductivity aluminum foils are pasted on the heat surface of the heat flow meter and the two sides of an electric heating film to promote uniform heat transfer, and heat preservationcotton is arranged around a test piece to reduce experimental errors caused by natural convection. The experimental device is good in matching, simple and convenient to operate and capable of achieving rapid and high-precision calibration of the thin film type heat flow meter.

Description

technical field [0001] The invention belongs to the technical field of heat measurement, and in particular relates to a high-precision calibration device and method for a thin-film heat flow meter. Background technique [0002] The heat flow meter is an instrument for measuring the heat flux and heat flux density on the surface of an object. It is widely used in power engineering, aerospace and other fields, and the accuracy of its measurement results is very important. The test principle of the heat flow meter is to obtain the heat flux density through the film by testing the temperature on both sides of the film with known thermal conductivity. The measurement errors of material thermal conductivity, thickness, and temperature will affect the measurement accuracy of the heat flow meter. On the one hand, the heat flow meter is a mass-produced product, and the uniformity affects the individual accuracy. It will not be calibrated one by one when leaving the factory; Factors ...

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Problems solved by technology

[0004] In order to realize the simple and high-precision calibration of thin-film heat flow meters, the present invention provides a high-precision calibration device and method for thin-film heat flow meters, which uses a steady-state plane heat source heating method to build a calibration system, which can improve the existing heat flow meters. In the calibration technology, the calibration device is complex and expensive, the experimental operation is difficult, and the operation time is long.

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