A test method for measuring low temperature thermal insulation performance of vacuum conveying pipe

Abstract

The invention relates to a test method for measuring the low-temperature thermal insulation performance of a vacuum conveying pipe, which belongs to the field of testing the thermal insulation performance of the vacuum conveying pipe at low temperature (in the liquid hydrogen temperature zone). The present invention adopts real low-temperature propellant (liquid hydrogen) to test, and both ends of the vacuum conveying pipe to be tested are connected with tooling filled with liquid hydrogen, which is consistent with the working state of the vacuum conveying pipe on the arrow; hydrogen (liquid hydrogen) has easy However, in the test system proposed by the present invention, the liquid hydrogen (liquid hydrogen) is isolated from the outside world, which is safe and reliable; the lower end of the vacuum delivery pipe to be tested is connected to the cold screen, and at the same time, the method of connecting the pipeline to the tooling can be The construction of the heat insulation structure minimizes the impact of heat leakage; the liquid hydrogen filling conduit has a U-shaped backwater bend structure to prevent liquid hydrogen vapor from overflowing from the liquid hydrogen filling conduit.

Description

technical field [0001] The invention relates to a test method for measuring the low-temperature thermal insulation performance of a vacuum conveying pipe, which belongs to the field of testing the thermal insulation performance of the vacuum conveying pipe at low temperature (in the liquid hydrogen temperature zone). Background technique [0002] The new generation of launch vehicle core-level liquid hydrogen delivery pipes adopts a vacuum condensation scheme to achieve pipe insulation. The vacuum conveying pipe is mainly composed of inner pipe and outer pipe, and also includes compensator, flange and other components to meet the needs of pipeline installation and compensation. In order to reduce the heat loss of the tube wall and improve the thermal insulation performance of the pipeline, the interlayer between the inner and outer tubes of the vacuum delivery tube must be evacuated before use and filled with carbon dioxide for protection, forming a double-layer vacuum pipel...

AI Technical Summary

Problems solved by technology

[0004] It is difficult to directly measure the low-temperature thermodynamic parameters of the vacuum conveying pipe. The main difficulties are: 1. The vacuum chamber of the conveying pipe is a closed structure, and it is difficult to arrange temperature measuring points in the vacuum chamber for temperature measurement; 2. The flanges and compensators at both ends of the vacuum conveying pipe etc. adopt the external insulation scheme, the insulation performance of the above components is significantly different from that of the vacuum tube part, so it is difficult to use a simple thermodynamic model to describe the insulation performance of the whole tube

Images