SU1363011A1 - Method of determining moisture content of materials - Google Patents

Abstract

The invention relates to K-4fer6baM studying the physical composition of natural materials and can be used to determine the moisture content of ice, snow, soils. The purpose of the invention is to improve the accuracy and performance of the determination. Samples were removed to determine the moisture content of the test medium. Then they are cooled and the moisture content is determined from the acoustic emission signals resulting from the crystallization of water in the samples. The main indicator of moisture content is the duration of the acoustic emission process. A liquid cooler, a Dewar vessel and receiving ultrasonic transducers are used to implement the method. The error of the method lies within the sensitivity of the ultrasonic transducer and is 0.1-0.5%. 1 hp f-ly. c & (L with O5 WITH

Description

 13

The invention relates to methods for studying the physical composition of natural materials and can be used (- in gliology, in particular, to determine the moisture content of ice, snow, soils and frozen soils.

The purpose of the invention is to improve the accuracy and performance of the determination.

The essence of the method is as follows.

In a sample of material, conditions are created for the crystallization of water contained in the material, during which acoustic emission signals occur, and acoustic emission parameters, such as its duration, are recorded. The duration of the acoustic emission process is recorded by an ultrasound transducer mounted on a sample of material. The duration of the acoustic emission process is called the time from the moment of occurrence until the moment of termination of the process. Since the duration of the acoustic emission process is directly proportional to the amount of water, it follows from the previously performed calibration charts that the amount of water contained in the sample of natural material.

As methods that cause crystallization of water, various methods can be used based on the reduction of temperature, for example, immersion in a liquid cooler (toluene) with a negative temperature.

The method is carried out as follows.

For the moisture content test, a material sample is taken in the form of a disk, the dimensions of which determine the choice of the object of study (for example, for snow, the dimensions of the disk are R 40 mm and h 20 mm). The receiving ultrasonic transducer is mounted on the sample under study from the end (or

Editor A.Revin

Compiled by S. Volkov

Tehred A. Kravchuk Proofreader A. Obruchar

Order 6395/31 Circulation 776 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

112

two converters from both ends connected to the preamplifier. A system of sample and transducer is installed in a cylindrical container (Dewar) with dimensions (internal) R 12 cm and H 20 cm.

After that a liquid cooler (for example, toluene) having a negative temperature (for example, at T) enters the tank. Water containing in the sample will crystallize and emit acoustic emission signals. The ultrasound transducer records the duration of the emission, which is proportional to the amount of water contained in the sample. The termination of the acoustic emission process indicates the completion of the crystallization of water in the sample volume. From the measured acoustic emission duration, taking into account the calibration dependence, the moisture content of the material sample is determined.

Claims (2)

1. A method for determining the moisture content of materials, based on the measurement of the energy consumed by a sample of a material during its cooling, characterized in that, in order to increase accuracy and performance, a sample of the material is cooled to the temperature of water crystallization in the sample, the parameters of acoustic emission in the process of water crystallization in the sample, according to which, taking into account the calibration dependence, the moisture content in the material sample is determined. 2. Method pop. 1, which differs from the fact that its duration is recorded as an acoustic emission parameter.