CN206788079U - A kind of thermal conductivity of frozen soils measure device of controllable temperature - Google Patents

Abstract

The utility model discloses a temperature-controllable thermal conductivity measuring device for frozen soil. Its structure is composed of two layers of plexiglass cylinders for heat preservation, upper and lower constant temperature cold bath plate temperature control device, the soil sample to be tested is placed in the cylinder, and the temperature sensor is placed inside the soil sample, and the internal temperature of the soil sample reaches a constant and uniform state. Finally, the upper constant temperature cold bath plate was turned on, and the thermal conductivity of the soil sample was measured by a rapid thermal conductivity tester (hot wire method). After the measurement, the soil sample was taken out, and the remaining parts of the device were dismantled. The device has precise temperature control and tight heat preservation, and can make the surface of the soil sample meet the test flatness requirements, thereby effectively reducing the measurement error and quickly measuring the thermal conductivity of the soil sample. The test process is simple to operate, the device is easy to install and disassemble, and the thermal conductivity of frozen soil at a specific temperature is accurately measured.

Description

A temperature-controllable thermal conductivity measuring device for frozen soil

technical field

The utility model relates to a temperature-controllable frozen soil thermal conductivity measuring device, which can be used to complete the thermal conductivity measurement of frozen soil samples under specific temperature conditions.

Background technique

The thermal conductivity of the same substance will vary with temperature, so the thermal conductivity is a function of the temperature of the substance. Since the temperature of a substance directly reflects the density of the molecules of the substance and the strength of the thermal motion, the thermal conductivity of the substance is closely related to the temperature. This requires that in the process of measuring the thermal conductivity of the test soil sample, the temperature of the soil sample must be precisely controlled, and the stability and uniformity of the internal temperature of the soil sample must be maintained. Therefore, a temperature-controllable thermal conductivity measurement method for frozen soil is developed device.

Utility model content

The technical problem to be solved by the utility model is a temperature-controllable frozen soil thermal conductivity measuring device, which can complete the measurement of the frozen soil sample thermal conductivity under specific temperature conditions and meet the test requirements.

In order to solve the above technical problems, the technical solution of the utility model patent is: a temperature-controllable frozen soil thermal conductivity measuring device, the key technology of which is: it includes an inner plexiglass cylinder, an outer organic glass cylinder outside the inner plexiglass cylinder. The glass cylinder, the upper constant temperature cold bath plate arranged on the upper part of the inner plexiglass cylinder, the lower constant temperature cold bath plate arranged on the lower part of the inner plexiglass cylinder, and the metal bracket for installing the lower constant temperature cold bath plate, the inner plexiglass cylinder and the The outer plexiglass cylinder is vacuum-sealed between the two to form a sleeve capable of heat preservation; the soil sample to be tested is placed on the lower constant temperature cold bath plate, and a probe for measuring thermal conductivity by a hot wire method is placed on the upper surface of the soil sample to be tested. A temperature sensor is embedded in the soil sample to be tested;

The upper constant temperature cold bath plate is provided with an upper constant temperature cold bath plate circulating bath liquid inlet and an upper constant temperature cold bath plate circulating bath liquid outlet, and the lower constant temperature cold bath plate is provided with a lower constant temperature cold bath plate circulating bath liquid inlet and a The outlet of the circulating bath liquid of the lower constant temperature cold bath plate.

As a further improvement, the upper constant temperature cold bath tray is provided with a temperature sensor inlet and a top plate handle.

As a further improvement, the exterior of the outer plexiglass cylinder is provided with a metal support that functions as an integral support.

Preferably, grooves for the circulation of the constant temperature bath liquid are planed on the upper constant temperature cold bath plate, and the circulation bath liquid inlet of the upper constant temperature cold bath plate and the circulation bath liquid outlet of the upper constant temperature cold bath plate are docked on the upper constant temperature cold bath plate notch.

The beneficial effects produced by adopting the above-mentioned technical scheme are:

1. The device adopts the upper and lower constant temperature cold bath plates to control the temperature. The materials of the upper constant temperature cold bath plate and the lower constant temperature cold bath plate are metal heat conduction plates with good heat transfer, and there are cold bath fluid circulation grooves inside. The connection of the external constant temperature bath testing machine can quickly and accurately control the temperature of the soil sample at a specific value, which is easy to operate, accurate and effective.

2. The utility model adopts inner and outer plexiglass barrels for heat preservation, and a temperature sensor for temperature measurement. Through the cooperation of temperature control, heat preservation, and temperature measurement components, the internal temperature of the soil sample to be tested is stabilized and evenly distributed, which greatly improves the accuracy of the thermal conductivity of frozen soil at different temperatures.

3. With this utility model, after the surface of the soil sample passes through the constant temperature cold bath plate, the temperature is constant, and the frost heave is generated while the surface is guaranteed to be smooth, which meets the basic requirements of the hot wire method for the determination of the thermal conductivity, and can quickly conduct heat conduction of the soil sample. Determination of coefficients.

4. The utility model realizes the controllability of the temperature of the soil sample in the process of measuring the thermal conductivity of the soil sample. The adjustable temperature range is large (-20°C to 20°C), and the temperature control accuracy is high (0.1°C), which meets the indoor The test is used to determine the thermal conductivity of frozen soil under specific temperature conditions, and the application effect is good.

Description of drawings

Fig. 1 is the utility model device schematic diagram;

Figure 2 is a working diagram of the measurement of thermal conductivity of a soil sample.

detailed description

In order to make the above purpose, features and advantages of the present utility model more obvious and easy to understand, the technical solutions in the embodiments of the present utility model will be clearly and completely described below in conjunction with the drawings and specific implementation methods in the embodiments of the present utility model Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

Referring to accompanying drawing 1 and accompanying drawing 2, the utility model comprises inner plexiglass cylinder 1, outer plexiglass cylinder 2, top plate handle 3, upper constant temperature cold bath plate 4, upper constant temperature cold bath plate circulating bath fluid inlet 7, upper constant temperature cold bath plate Circulating liquid outlet of bath plate 8, lower constant temperature cold bath plate 6, lower constant temperature cold bath plate circulating bath liquid inlet 10, lower constant temperature cold bath plate circulating bath liquid outlet 11, metal bracket 12, metal support 13, temperature sensor inlet 14 and temperature sensor 15.

Inner plexiglass cylinder 1 adopts the plexiglass plate that thickness is 1cm, makes high 35cm, the cylinder of internal diameter 20cm. Outer plexiglass cylinder 2 adopts the plexiglass plate that thickness is 1cm, height 35cm, internal diameter 25cm. The inner plexiglass cylinder 1 is placed inside the outer plexiglass cylinder 2, and the two layers of plexiglass cylinders are evacuated and sealed to form a thermal insulation sleeve. The bottom of the sleeve is fixedly connected with the lower constant temperature cold bath plate 6 and placed on the metal support 12. The lower part of the lower constant temperature cold bath plate 6 is provided with the lower constant temperature cold bath plate circulation bath liquid inlet 10 and the lower constant temperature cold bath plate circulation bath liquid Outlet 11 is connected with the external constant temperature cold bath testing machine, and the constant temperature is provided by the external constant temperature cold bath testing machine. The soil sample 5 to be tested is placed in the inner plexiglass cylinder 1, on the lower constant temperature cold bath plate 6, and is close to the lower constant temperature cold bath plate 6, so that the soil sample reaches the constant temperature stable stage, and the upper constant temperature cold bath plate should also be in contact with the soil. The samples are in close contact, which can ensure the surface of the soil sample is flat while frost heaving. The upper constant temperature cold bath plate 4 is placed on the surface of the soil sample, and its height is adjustable. In the stage of making the temperature of the soil sample constant, it is also necessary to make the soil sample and the upper constant temperature cold bath plate 4 close to each other. In the stage of measuring the thermal conductivity of the soil sample, the upper constant temperature cold bath plate 4 is removed, the probe 9 for measuring the thermal conductivity by the hot wire method is placed on the soil sample, and the thermal conductivity of the soil sample is measured by connecting the heating wire to an external rapid thermal conductivity measuring instrument. The thermal conductivity measuring probe 9 is connected with a rapid thermal conductivity measuring instrument 16 . The upper constant temperature cold bath plate 4 is made of metal material with good thermal conductivity, and there is a cold bath liquid circulation groove on it, and the notches are respectively connected with the upper constant temperature cold bath plate circulation bath liquid inlet 7 and the upper constant temperature cold bath plate circulation bath liquid outlet 8 Docking, the top plate handle 3 is installed on the upper constant temperature cold bath tray 4, which is convenient for taking samples and measuring thermal conductivity. The upper constant temperature cold bath plate is also connected to the external constant temperature cold bath testing machine through the upper constant temperature cold bath plate circulating fluid inlet and the upper constant temperature cold bath plate circulating fluid outlet to provide a specific temperature for the soil sample. When measuring the thermal conductivity of the soil sample 5 to be tested in the inner plexiglass cylinder 1, a temperature sensor probe 15 is placed in the middle of the soil sample 5 to be tested. The lower constant temperature cold bath tray 6 is also planed with grooves for the circulation of the constant temperature bath liquid.

Referring to accompanying drawing 2, adopt this device to measure the concrete process of soil sample thermal conductivity as follows: adopt QTM-500 model rapid thermal conductivity tester to test, place the soil sample 5 to be tested in the inner plexiglass cylinder 1, make the soil sample to be tested 5. In close contact with the upper constant temperature cold bath plate 4 and the lower constant temperature cold bath plate 6, when the temperature sensor 15 shows that the internal constant temperature of the soil sample is stable, enter the stage of measuring the thermal conductivity of the soil sample, take away the upper constant temperature cold bath plate 4, and still make the sample to be tested The soil sample 5 is in close contact with the lower constant temperature cold bath plate 6 .

The specific connection is shown in Figure 2: the upper constant temperature cold bath plate circulating bath liquid inlet 7 and the lower constant temperature cold bath plate circulating bath liquid inlet 10 of the device are connected with the external constant temperature bath testing machine outlet 18; the upper constant temperature cold bath plate circulating bath liquid outlet 8 Connect with the outlet 11 of the circulating bath liquid of the lower constant temperature cold bath plate and the inlet 17 of the external constant temperature bath testing machine; the heating line 19 connects the probe 9 for measuring the thermal conductivity by the hot wire method with the rapid thermal conductivity measuring instrument 16; the temperature sensor 15 is connected with the temperature collector 20 .

The utility model has precise temperature control and tight heat preservation, and can make the surface of the soil sample meet the test flatness requirement, thereby effectively reducing the measurement error and quickly measuring the thermal conductivity of the soil sample. The test process is simple to operate, the device is easy to install and disassemble, and the thermal conductivity of frozen soil at a specific temperature is accurately measured.

Claims (4)

1. A kind of 1. thermal conductivity of frozen soils measure device of controllable temperature, it is characterised in that：It includes interior lucite cylinder（1）, be located at Interior lucite cylinder（1）Outside outer lucite cylinder（2）, located at interior lucite cylinder（1）The upper thermostated cooling bath disk on top（4） With located at interior lucite cylinder（1）With outer lucite cylinder（2）The lower thermostated cooling bath disk of bottom（6）And for installing lower constant temperature Cryostat dish（6）Metallic support（12）, the interior lucite cylinder（1）With outer lucite cylinder（2）Vacuum sealing between the two, Form the sleeve that can be incubated；The lower thermostated cooling bath disk（6）Soil sample to be measured is placed above, the soil sample upper surface to be measured is set There is Hot Wire Technique for Measuring thermal conductivity factor probe（9）, temperature sensor is embedded with the soil sample to be measured（15）；The upper thermostated cooling bath Disk（4）It is provided with the circulation body lotion import of upper thermostated cooling bath disk（7）With the outlet of upper thermostated cooling bath disk circulation body lotion（8）, the lower perseverance Warm cryostat dish（6）It is provided with the circulation body lotion import of lower thermostated cooling bath disk（10）With the outlet of lower thermostated cooling bath disk circulation body lotion（11）.
2. 2. a kind of thermal conductivity of frozen soils measure device of controllable temperature according to claim 1, it is characterized in that：The upper constant temperature Cryostat dish（4）It is provided with temperature sensor import（14）With top plate handle（3）.
3. 3. a kind of thermal conductivity of frozen soils measure device of controllable temperature according to claim 1, it is characterized in that：It is described outer organic Glass infuser（2）Outside is provided with the metal support for playing integrated support effect（13）.
4. 4. a kind of thermal conductivity of frozen soils measure device of controllable temperature according to claim 1, it is characterized in that：It is cold in upper constant temperature Bath（4）Upper plane has the cutting for the circulation of constant temperature body lotion, the upper thermostated cooling bath disk circulation body lotion import（7）With upper thermostated cooling bath The outlet of disk circulation body lotion（8）Butt up against thermostated cooling bath disk（4）On notch；The lower thermostated cooling bath disk（6）On also plane have confession The cutting of constant temperature body lotion circulation.