SU1504364A1 - Method of stabilizing rotary pump delivery - Google Patents

Abstract

The invention relates to hydraulic machine building and allows simplifying the test technology of a pump on a cryogenic working body and reducing its required quantity. At the outlet of the pump, the liquid working fluid is divided into two streams, one of which is cooled by direct interaction with the working fluid in a solid state. Then, the cooled and non-cooled streams are mixed before entering the pump, which makes it possible to regulate the temperature within the specified limits up to the temperature of the triple point without using an additional cooler. 1 il.

Description

The invention relates to hydraulic engineering and can be used to test a pump on a cryogenic working body.

The aim of the invention is to simplify the testing technology and reduce the required number of workers. body.

The drawing shows the layout of the test stand, through which the pump is tested in accordance with the present method.

The test bench includes a test clock 1 with a drive 2, a suction line 3, on which mixer 4 is installed, a pressure line 5 connected to accumulative part 6 of supply tank 7 through pipeline 8 and to thermostatic part 9 of supply tank 7 through pipeline 10. To mixer 4 are connected a pipe 11 and 12 connected respectively to the storage and thermostatic parts 6 and 9 of the supply tank 7. Regulators 13 and 14 are placed on pipelines 8 and 10, respectively. Similar regulating bodies It can be installed on pipelines 11 and 12 to create and maintain the desired flow rate ratio and temperature of the working fluid.

The tests of pump 1 in accordance with the proposed method are carried out in the following sequence.

Before starting the tests, the accumulative part 6 of the container 7 is filled with a liquid working fluid, and the thermostatic part 9 is filled with the working fluid in a solid state. The test pump 1 circulates the working fluid in the circuit of the stand. The working fluid at the outlet of the pump 1 is divided into two streams, one of which enters the thermostat 1 of the fresh part 9 of the feed tank 7, where this flow

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cools upon interaction with a chiller. The other stream enters the accumulative part 6 of the container 7. At the exit from the latter, both streams are swept out before entering the pump 1. In this case, the working fluid is used as an cooler in an aggregative state other than liquid, namely in the solid state, and its interaction with a cooled liquid working fluid is carried out directly in the stream of the latter. When pumping a liquid working fluid, its temperature and enthalpy increase. During the interaction of a part of the working fluid with a coolant, the latter absorbs heat, both due to the heating of the previously cooled solid working fluid to the melting point, and phase transitions that are not associated with a change in the state of aggregation, and then melt. In this case, the heat transfer coefficient from liquid to working medium in a solid state can reach significant values, which is caused by the direct contact between the solid and liquid phases of the working fluid and high energy intensity of phase and aggregate transitions.

The flow temperature at the outlet of the thermostatic part 9 of the tank 7 is reduced compared with the temperature at the outlet of the pump 1, in the limiting case to the temperature of the triple point. After mixing the flows coming from the two parts 6 and 9 of the supply tank 7, the flow having the required consumption and temperature values is supplied to the entrance to the pump 1. This is achieved by adjusting the ratio of the flow rate of the working fluid entering the thermostatic and accumulative parts 6 and 9 of the supply tank 7, adjusting the heat exchange process itself by changing the flow rate washing the solid working body and the total area the layout and design of the supply container 7, which determine the possibility of heat exchange between its parts 6 and 9.

In the limiting case, when only the flow past the thermostatting part 9 of the tank 7 enters the pump 1, it can be tested

nor at the temperature of the working fluid close to or equal to the temperature of the triple point.

In addition, as a result of melting the working fluid in a solid state, the total amount of the working fluid in a liquid state increases, which makes it possible to compensate for leaks from the circuit of the stand.

The minimum required amount of working heat in solid state dp for testing a given duration can be obtained by the following relationship:

W

GU. -SnSO / M, - 1

1 -I- (H1t

T5

where M is the mass of the liquid worker

the body, located in the supply tank 7 at the beginning of the test, kg;

M g - the mass of the working fluid in

solid state, which is in the supply tank 7 at the beginning of the test, kg; with

С „- mass“ flow rate of the working fluid through the pump, kg / s;

  set test duration, s; H - to, n, d. pump;

H - pump head, J / kg; ul, is the change in the enthalpy of the working body when its temperature changes from the temperature of the solid state at the beginning of the test to the specified temperature at the pump inlet (including latent heats of phase transitions), J / kg,

This method eliminates the external cooling system while simultaneously expanding the range of temperatures in terms of temperature and compensates for leaks, which simplifies the testing technology and reduces the required amount of working fluid.

Claims (1)

Invention Formula A method of testing a pump that is included in the circulation circuit of the working fluid, by dividing the last I at the pump outlet into two streams, one of which is cooled during operation with the cooler, and the subsequent mixing of both streams before entering the vB pump; a working medium is used in an aggregate state other than a liquid one, characterized in that, in order to simplify the process, 15043646 The logic of testing and reducing the required amount of working fluid, as a coolant, use the working fluid in a solid state, while its interaction with the cooled working fluid is carried out directly in the flow of the latter. AND