Near-phase change zone frozen soil thermal conductivity coefficient determination device and method

Abstract

The invention relates to a device and method for steady-state determination of near-phase change zone frozen soil thermal conductivity coefficient, and the device and method are especially suitable for measurement of the frozen soil thermal conductivity coefficient change under multiple temperature points within a high temperature section. The device is composed of a constant temperature apparatus I, a constant temperature apparatus II, a tubular soil sample chamber, a heat flux sensor, cold liquid circulating plates, a probe type temperature sensor I, and a probe type temperature sensor II. The cold liquid circulating plates are arranged at the left end and right end of the tubular soil sample chamber respectively, and one end is equipped with the heat flux sensor. The cold liquid circulating plates are connected to the high-low temperature constant liquid circulating apparatus I and the high-low temperature constant liquid circulating apparatus II through silica gel pipes, the probe type temperature sensors are inserted into the tubular soil sample chamber, the cold liquid circulating plates at both ends are connected to the constant temperature apparatuses through the silica gel pipes, and the temperature values at both ends of a frozen soil sample are controlled by the constant temperature apparatuses at a highest temperature value and lowest temperature value of the sample phase change zone. The device has a simple structure, the measurement method is simple, and the measurement accuracy is high.

Description

technical field [0001] The invention relates to a thermal conductivity measuring device and method, and is especially suitable for measuring the thermal conductivity change of frozen soil at multiple temperature points in a high-temperature section, and the device and method for measuring the thermal conductivity of frozen soil in a near-phase transition zone. Background technique [0002] The measurement of thermal conductivity of frozen soil is an important index to evaluate the heat transfer performance and thermal stability of frozen soil materials. There are two main types of measurement methods for the thermal conductivity of frozen soil: based on the steady state method and based on the transient state method. The test principle of the thermal conductivity tester based on the transient method is that the test probe releases heat instantaneously, then detects the temperature rise gradient, and then calculates the thermal conductivity of the material to be tested, which...

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Problems solved by technology

Therefore, there are essential differences between the thermal conductivity measurement results based on the steady-state method and the real distribution pattern and specific value of the thermal conductivity of permafrost in the phase transition zone.

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