SU551538A1

SU551538A1 - Capillary Viscometer

Info

Publication number: SU551538A1
Application number: SU2074396A
Authority: SU
Inventors: Марк Леонидович Фрисман; Юрий Константинович Сафонов
Original assignee: Всесоюзное научно-производственное объединение целлюлозно-бумажной промышленности
Priority date: 1974-11-11
Filing date: 1974-11-11
Publication date: 1977-03-25

Description

1Изобретение относитс к области исследовани реологических свойств дисперсных систем и может быть использовано, в частности, в целлюлозно-бумажной промышленности при исследовани х сульфидных смесей.51The invention relates to the field of research of the rheological properties of dispersed systems and can be used, in particular, in the pulp and paper industry in the study of sulfide mixtures.5

Известен капилл рный вискозиметр, содержащий герметичный сосуд дл исследуемой жидкости, капилл р, расположенный в нижнем торце сосуда, измеритель давлени I .A capillary viscometer is known, containing a pressurized vessel for the test liquid, a capillary located at the bottom of the vessel, a pressure meter I.

Капилл р соединен с торцом герметично- Ю го сосуда в его нижней части посредством накидной гайки. Верхн часть сосуда соединена трубкой с компрессором, причем между сосудами и компрессором имеетс воздушный редуктор дл регулировани давлени 15 воздуха. Процесс исследовани в зкости на капилл рном вискозиметре заключаетс в измерении потерь напора на определенной рабочей длине капилл ра и соответствующего им расхода исследуемой жидкое- 20 ти. За рабочую длину обычно принимают полную длину капилл ра, т.е. участок от входного до выходного сечени .The capillary tube is connected to the end of a hermetic vessel in its lower part by means of a cap nut. The upper part of the vessel is connected by a tube to a compressor, and there is an air reducer between the vessels and the compressor to regulate the air pressure 15. The process of viscosity testing on a capillary viscometer is to measure head losses over a certain working length of the capillary and the corresponding flow rate of the liquid under study. The full length of the capillary is usually taken as the working length, i.e. plot from the input to the output section.

Недостатком известного капилл рного вискозиметра вл етс снижение точности изме- 25A disadvantage of the known capillary viscometer is a decrease in the accuracy of the measurement.

рений из-за наличи так называемого входвого эффекта, заключающегос в том, что частицы жидкости, вдоль оси последнего постепенно разгон ютс приложенным извне перепадом давлени до скорости установившегос стабилизированного течени , и энерги , затрачиваема в этом процессе пространственного ускорени . 5тл етс причиной дополнительных потерь давлени , возникающих по сравнению с областью установившегос течени . Поэтому при обработке данны приходитс учитывать потери напора, обусловленные входовым эффектом.Rhenium due to the presence of the so-called input effect, which consists in the fact that the particles of liquid along the axis of the latter are gradually accelerated by externally applied pressure drop to a steady-state stabilized flow velocity and the energy expended in this process of spatial acceleration. It is responsible for the additional pressure losses occurring in comparison with the steady-state flow region. Therefore, the processing of data has to take into account the pressure loss caused by the input effect.

Цель изобретени - повышение точности измерений при исследовании реологических свойств жидкостей в капилл рном вискозиметре .The purpose of the invention is to improve the measurement accuracy when studying the rheological properties of liquids in a capillary viscometer.

Claims

This is achieved in that the capillary viscometer is equipped with a tube, one horse of which is connected to a hermetic vessel in its upper part, and the other to a capillary in a place lagging behind the input section of the capillary at a distance of not less than the diameters of the capillary. The drawing shows a diagram of a capillary viscometer. The viscometer consists of a capillary 1, a sealed vessel 2, a device for measuring pressure in a vessel, such as a pressure gauge 3, the air cavity of a sealed vessel located at the surface above the level of the test liquid, the tube 4 is connected to the internal cavity of the capillary. The distance from the input edge of the capillary 1 to the point of its connection with the tube 4 must be at least 20-30 of its diameter, which guarantees at this point a stabilized flow with a fully formed profile. The capillary viscometer works as follows. The test liquid is poured into the hermetic vessel 2 with the capillary 1 closed with a stopper at the end. After installing the valve, the vessel is connected to the compressed air line, by means of which the necessary pressure in the vessel is established by pressure gauge 3. This pressure is kept constant throughout the experiment. After opening the bottom ring of the capillary, the flow rate is measured using a measuring container and a stopwatch. At the same time, the pressure PM of the manometer 3 and the height of the liquid column in the tube 4 are recorded. The pressure loss D P at the working length of the capillary t slave. are found from the expression (o ,. where Y is the specific gravity of the liquid under study. Since the point of connection of tube 4 with capillary 1 is separated from the entrance edge of the capillary at a distance of 20-30 capillary diameters, at this point the stabilized flow is surely guaranteed Due to the fact that the pressure loss at the inlet section of the capillary (from the inlet section to the point of connection with the tube 4) remained outside the working length of the capillary (these losses are expressed by the height of the pillar All, part of them is due to the input effect) The running effect is completely eliminated, and the measurement accuracy is improved. The capillary viscometer can halve the experiment time, since to take into account the input effect, it is necessary to double the amount of research on capillaries of different lengths The capillary viscometer containing a sealed vessel for the liquid under investigation a capillary located at the bottom of the vessel, a pressure gauge, characterized in that, in order to improve the measurement accuracy, it is provided with a tube, one end of which is connected to the seal in the upper part of the vessel, and the other with the capillary in a place that is at least 20–30 times the diameter of the capillary from the inlet section of the capillary. Sources of information taken into account in the examination: 1. Smoldyrev A.Ye., Safonov Yu.K. Pipeline transport of concentrated slurries, Mashchinostroenie, M., 1973, p. 63 (prototype).

Compressed