Device and method for on-site accurate testing of heat conductivity of energy-saving thermal insulation materials

Abstract

The invention provides a device and method for on-site accurate testing of heat conductivity of energy-saving thermal insulation materials, and belongs to the technical field of energy-saving thermal insulation material thermal characteristic testing. The device comprises a self-adaptation thermal response detector, an electric signal collection module and a data processing module. The device is adopted for performing on-site testing on the energy-saving thermal insulation materials, fundamental wave voltage (V1omega)y and third harmonic voltage (V3omega)y of a to-be-tested sample are obtained; resistor temperature coefficient beta, core belt length l, substrate thermal conductivity ks of a calibrated thermal response temperature testing unit before usage and the fundamental wave voltage (V1omega)y and third harmonic voltage (V3omega)y of the to-be-tested sample are adopted for calculating the thermal conductivity of the to-be-tested sample. According to the device and method, the defects that an existing experimental system is not high in signal stability, not high in tested resistance precision and poor in differential signal can be overcome, and on-site accurate testing of the heat conductivity of thermal insulation materials is ensured.

Description

technical field [0001] The invention relates to the technical field of thermal characteristic testing of energy-saving and heat-insulating materials, in particular to a device and method for on-site accurate testing of thermal conductivity of energy-saving and heat-insulating materials. Background technique [0002] Heat insulation material is an energy-saving material that can significantly hinder convective heat transfer. The thermal insulation material uses the confined air in the internal pore structure (the thermal conductivity is only 0.026W / m K) to form a whole material with low thermal conductivity, so as to achieve the effect of thermal insulation and energy saving. Due to its good heat insulation and cold insulation properties, heat insulation materials are widely used in construction, metallurgy, chemical industry, electric power, petroleum, machinery, military industry, transportation, storage and other industries. It plays a very important role in our national ...

AI Technical Summary

Problems solved by technology

However, the measurement period of the protected hot plate method is long, and the sample size is required to be large, so it is impossible to realize the on-site test

When testing different materials with the transient plane heat source method, different detectors need to be replaced, and the material must be cut and surface polished in advance, which increases the tediousness of the test

The harmonic detection method has advantages over other methods in the measurement of thermal properties of micro-scale materials, but when it is used for the measurement of thermal insulation materials, the existing detectors cannot achieve in-situ testing, and the existing experimental circuits cannot guarantee the thermal conductivity. Accurate testing of extremely low samples

[0004] The existing technology (ZL200910242362.0) uses harmonic detection technology to test thermal conductivity. When this device measures solid materials, an independent probe is sandwiched between two identical samples to be tested. This operating feature cannot realize energy-saving and heat-insulating materials. On-site in-situ testing (especially for building materials)

In addition, the electrical signal acquisition system used in the prior art does not filter the original signal, the selection of main components such as power supply and differential amplifier is relatively rough, and the resistance terminal uses the "two-wire method" test, these factors will definitely affect Measurement accuracy

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