SU898269A1 - Hydraulic chamber for testing pressure pickups - Google Patents

Description

one

The invention relates to instrumentation, in particular to devices for dynamic testing of pressure sensors.

A device for calibrating pressure sensors is known, which contains a sealed chamber with two electrodes and a pulse discharge 1.

However, the known device does not provide high precision calibration of pressure sensors.

The closest in technical essence and achievable technical effect to the proposed device is a hydraulic chamber for dynamic testing of pressure sensors, comprising a chamber with an explosive device located in it and a valve for supplying pressure. The passage of the shock wave front inside a camel can be caused by undermining the suspension of the explosive substance inside it, and the shape of the suspension and changing the way it is initiated can affect the shape of the front of the excited shock wave. As a result of the hinge initiation in the chamber, a high pressure occurs, corresponding to the peak pressure of the compression phase of the shock H1O wave, which

field conditions quickly drop to static pressure at a given depth of 2.

However, the known device does not provide a high precision of calibration, since it does not make it possible to obtain a different form of pressure pulse.

The purpose of the invention is to improve the accuracy of the calibration of pressure sensors.

This goal is achieved by introducing a glass with a piston placed in it into the hydraulic chamber for dynamic testing of pressure sensors, while the open end of the glass is hermetically connected to the chamber, and holes are made in the walls of the glass.

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The drawing shows hydrobarocamera.

The hydraulic chamber 1 is equipped with a cylinder 2 with a piston 3 and a valve 4. The test object 5 and the explosive device with a plate explosion are placed below the water level to excite the underwater shock wave. To supply a static pressure, there is an inlet 30 valve 7.

Installation tests are performed in the following order. After the test article and the explosive device are installed in the hydraulic chamber to excite the underwater shock wave with the valve 4 open, air is forced under the chamber lid through the inlet valve 7 to a pressure corresponding to the stationary pressure at the immersion depth. By closing the valve 4, the hydrobarocampra is put on standby for testing. In this state, the pressure under the piston 3 (inside the chamber) and above the piston in the cylinder 2 is equal to the pressure at the simulated depth of the test sample. After the device 6 is blown up, a shock wave propagates in all directions and the intracameral pressure increases to the required pressure peak in the wave front, the value of which can be controlled by the charge and the ratio of this value to the volume of the air bubble under the cover of the hydro chamber. The intensity of the wave front acting on the test sample also depends on the distance of the sample to the device. B. Due to the increase in intra-chamber pressure under the cover of the hydraulic chamber and under the piston 3, the latter moves in cylinder 2, additionally compressing the air inside it. The pressure in cylinder 2 serves as the limit to which the intra-chamber pressure is vented. The speed of discharge of intra-chamber pressure is determined by the area of the exhaust ports and the dynamics of the movement of the piston inside the cylinder. An increase in the mass of the piston leads to an increase in its inertia, and hence to a decrease in the rate of depressurization of the excess pressure inside the chamber. Thus, the time of the compression phase in a wave can be varied by changing the magnitude of the piston mass.

Claims (2)

1. USSR author's certificate number 491060, cl. G 01 L 27/00, 1973.  2. US patent No. 3905234, cl. 73-4, 1975 (prototype).