RU2045034C1 - Method for determining porosity of bodies - Google Patents

Abstract

FIELD: investigation of physical properties of substances; analysis of structural parameters of porous bodies; engineering spheres where such bodies are used. SUBSTANCE: auxiliary specimen is placed in thin flexible sealed enclosure so that it is free from air and placed in chamber. Other chamber accommodates specimen being investigated and thin flexible enclosure. Both chambers and capillary tubes are filled with working fluid of equal volume up to top visible edges of capillary tubes. Specimens are subjected to desired pressure from pressure source with liquid of different color. Porosity of contracted and swelling bodies is determined at any desired pressures by measuring difference in levels of working liquid on color boundary in capillary tubes. EFFECT: facilitated procedure. 1 dwg

Description

 The invention relates to techniques for studying the physical properties of substances, namely, studying the structural parameters of porous bodies, and can be used in technical fields where such bodies are used.

A known method for determining the porosity of rocks by measuring the volume of fluid displaced from the pores of the sample when exposed to reservoir temperatures and pressures, the rock sample saturated with the formation fluid is subjected to an inter-threshold pressure and a comprehensive crimping pressure that are equal to the formation pressure and then the comprehensive crimping pressure is increased to values of rock pressure at the depth of the rock, maintaining the pressure in the pores of the sample using the pressure limit valve equal to the reservoir, and by the volume of mercury etched by the valve from the vessel in communication with the pore volume of the sample, determine the desired value [1]
There is also a method of determining porosity, which consists in saturating the test sample with a wetting liquid by bringing it into contact with an auxiliary sample, followed by measuring the amount of fluid contained in the pores of the test sample [2]
The disadvantage of this method is that it is impossible with good accuracy to measure the porosity of compressible and swellable bodies operated under compression pressure.

 The purpose of the invention is to improve the measurement accuracy by eliminating the influence of compressibility and swelling of the test sample.

 For this purpose, a sample is selected as an auxiliary sample, in which the geometry and material are the same with the test sample, placed in a thin elastic sealed shell, both samples are placed in two chambers of the same volume, and the same flexible shell is placed in the chamber with the test sample, the chambers are filled with equal volumes of the working fluid, the samples are loaded with a liquid of a different color supplied through capillaries connected to the same pressure source, and by the difference in the levels of the working fluid in the capillary x determine the desired value at any pressure.

 The drawing shows a device for implementing the proposed method.

 The device includes two identical in volume chambers 1 and 2, connected through capillaries 3 and 4 to a pressure source (not shown). The test sample 5 and a thin elastic shell 6 are placed in the chamber 1. An auxiliary sample 7 is placed in the chamber 2, in which the geometry and material are the same as the test sample 5, placed in a thin elastic hermetic shell 8. The shells 6 and 8 are identical in size and material.

 The device operates as follows.

Auxiliary sample 7 is placed in a thin elastic sealed shell 8 so that there is no air, and installed in chamber 2. In the chamber 1, the test sample 5 and a thin elastic shell 6 are placed. Chamber 1 together with capillary 3 and chamber 2 together with capillary 4 they are filled with equal volumes of the working fluid to the upper visible sections of the capillaries 3 and 4. Loading of the specimens 5 and 7 with a given pressure is carried out from a pressure source (not shown) with a liquid of a different color. Volume changes in chamber 1 at a given pressure are calculated by the formula
ΔV ₁ ΔV _{compression volume 1} + ΔV _{compression volume 1} + ΔV _{compression weight} + + ΔV _compression volume ₁ where ΔV _compression volume 1 volume change caused by compressibility of sample 5;
ΔV _{por. About 1} volume change caused by the porosity of sample 5;
ΔV _{compress. 1} change in volume caused by compressibility of the working fluid;
ΔV _compress . Volume 1 volume change caused by compressibility of the elastic shell 6.

The change in volume in chamber 2 at a given pressure is calculated by the formula
ΔV ₂ Δ V _{compress. 2} + ΔV _{compress. 2} + ΔV _{compress. 2} where ΔV _compress . 2 volume change caused by the compressibility of sample 7;
ΔV _{compress.zh.2} volume change caused by the compressibility of the working fluid;
ΔV _compression volume 2 volume change caused by compressibility of the elastic shell 8.

Considering that samples 5 and 7 with the same geometry and material, the volumes of chamber 1 and 2 are equal, therefore, the volumes of working fluids in them are equal, and the shells 6 and 8 are identical in size and material, we obtain a change in volume caused by porosity at a given pressure
ΔV ΔV ₁ + ΔV ₂ + ΔV ΔV _{szh.ob.1 por.ob.1 szh.zh.1} + ΔV + ΔV _szh.ob.1 - -ΔV _{szh.ob.2 szh.zh.2} ΔV ΔV _{compression channel. vol.2} ΔV _por.ob.1
Thus, by measuring the difference in the levels of the working fluid in capillaries 3 and 4, the porosity of compressible and swelling bodies at any pressure is determined.

Claims (1)

 METHOD FOR DETERMINING BODY POROSITY, which consists in saturating the test sample with a wetting liquid followed by measuring the amount of liquid contained in the pores of the test sample, as well as in using an auxiliary sample, characterized in that a sample is selected as an auxiliary sample in which the geometry and material are the same as the test sample, place it in a thin elastic tight hermetic shell, both samples are placed in two equally sized chambers, in addition, in the chamber with the sample the same elastic shell is placed, the chambers are filled with equal volumes of the working fluid, the samples are loaded using a miscible with the working fluid with a color different from the color of the working fluid supplied through capillaries connected to the same pressure source, and determined by the difference in the levels of the working fluid in the capillaries the desired value of porosity.

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