An Experimental System for Direct Measurement of Permafrost Permeability

Abstract

The invention relates to an experimental system for directly measuring permeation characteristics of frozen soil, which relates to the field of frozen soil measurement. The invention aims to solve the direct measurement of the permeability characteristics of saturated frozen soil. Technical points: the measuring section is used to measure the permeability characteristics of the sample frozen soil; the gradient section is used to reduce the moisture temperature in the gap between soil particles to the measurement temperature; the temperature control system is used to maintain a constant temperature in the measuring section and ensure The temperature gradient changes in the gradient section; the inlet constant pressure system is used to ensure the constant inlet fluid pressure; the flow measurement system is used to measure the permeate fluid flow. The measurement of the permeability characteristics of frozen soil solves the problem of the difficulty of injection of super-low temperature fluid through the connection of the gradient section and the measurement section, making the direct measurement of frozen soil feasible. The gradual change section adopts the method of alternating high and low temperature temperature control coils, which makes the temperature gradient controllability of the gradual change section stronger. The inlet constant pressure system can flexibly adjust different inlet pressures according to the experimental requirements.

Description

technical field [0001] The invention relates to the field of frozen soil measurement, in particular to an experimental system for directly measuring the permeability characteristics of frozen soil. Background technique [0002] When the saturated soil freezes, there will still be some unfrozen water in the soil. The reasons for this phenomenon are: (1) The molecular interaction force between the soil particles and the ice, when the gap between the soil particles and the ice layer decreases To a certain extent, due to the intermolecular repulsion between the soil particles and the ice, a certain gap will be maintained between the soil particles and the ice layer. (2) The influence of the interfacial tension of ice and water. The Gibbs free energy of will increase. The existence of unfrozen water provides flow channels for permafrost infiltration to a certain extent. In cold regions, climate change will cause water and heat migration in permafrost, which will greatly affect ...

AI Technical Summary

Problems solved by technology

[0003] An object of the present invention is to provide a direct measurement experimental system of permafrost permeability characteristics to solve the problem of direct measurement of saturated permafrost permeability characteristics

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