Slit-type cold head used for coaxial-type pulse pipe refrigerator and provided with flow guiding structures and manufacturing method

Abstract

The invention discloses a slit-type cold head used for a coaxial-type pulse pipe refrigerator and provided with flow guiding structures and a manufacturing method. The slit-type cold head comprises acold head main body, an anti-deformation pad, a red copper wire mesh and a cold end baffle. The cold head main body and the anti-deformation pad generate a threaded hole jointly after brazing; a cylindrical groove is formed in the cold head main body to be matched with the cold end baffle, and the red copper wire mesh is tightly pressed by the cylindrical groove and the cold end baffle; a plurality of slits are evenly distributed in the cold head main body in an axial symmetry mode; the two round angle flow guiding structures are arranged at the 180-degree bending positions of slit flow channels; and the slits provided with the flow guiding structures are formed through mould electric spark machining. In the slit-type cold head of the coaxial-type pulse pipe refrigerator, the slit flow guiding structures are optimized, meanwhile the maximum heat exchanging area is achieved, the flow loss in the cold head is reduced, and the whole machine performance of the coaxial-type pulse pipe refrigerator is improved.

Description

technical field [0001] The invention relates to a coaxial pulse tube refrigerator, in particular to a slit cold head with a guide structure and a manufacturing method thereof. Background technique [0002] The pulse tube refrigerator is a new type of regenerative cryogenic refrigerator. Compared with the traditional Stirling refrigerator, it eliminates the mechanical moving parts at the cold end, and uses the phase adjustment mechanism at the hot end to obtain the ideal phase relationship. It has a simple structure , small vibration, high reliability and so on. Since the 1980s, pulse tube refrigerators have received extensive attention and research at home and abroad, and have been widely used in aerospace, superconducting industry, low-temperature electronics, and low-temperature medicine. With the in-depth study of the mechanism of pulse tube refrigeration and the gradual improvement of the steering mechanism, the technology of pulse tube refrigerators is becoming more an...

AI Technical Summary

Problems solved by technology

figure 2 In the coaxial cold head shown, the slit of the cold head cuts through the outer cylindrical surface and the flow channel of the working fluid is rectangular, without a flow guide structure, so the void volume caused by the bending of the inner flow channel of the cold head cannot be reduced, which will deteriorate Heat transfer performance of cold head

image 3 The flow path of the coaxial cold head shown is also rectangular, and the void volume caused by the bending of the inner flow path of the cold head cannot be reduced; in addition, the external main heat exchange surface of the cold head is located The thermal slit is located in the bottom cooling head, so there is an additional contact thermal resistance in the middle of the heat conduction path, which affects the heat transfer performance

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