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Abstract

The oscillating tube is among the primary element of the Gas Wave Refrigerator,it shoulders the task of energy dissipation.So,in order to assure the need of the Gas Wave Refrigerator,the length of the oscillating tube is generally longer,and the temperature of the oscillating tube at the end is lower,the investigation result of the distributing of the oscillating tube wall temperature is relative lake.At the same time,the investigation indicated that the isentropic refrigeration efficiency of the actual Gas Wave Refrigerator undulates consumingly following the changing of the jet flow frequency,and that affected the adaption ability of the Gas Wave Refrigerator.Aiming at those two matters,the method of combination of experimental and numerical simulation is adopted by this paper to analyse the fluxion in the oscillating tub deeply.The amelioration method of the oscillating tube structure is put forward and the systemic experiment and the numerical value analyse for the new type oscillating tube (the Intersection Oscillating Tube) has been done,that lays the foundation for practice application.In this paper,the main work andthe main conclusions are as follows:(1) The logical experiment platform and test system are established to accomplish the many experimental works on oscillating tube,such as the inner transient pressure,the outer wall temperature,the refrigeration performance and the structure optimization.A numerical model of GWR is set up which can complete the multi-period computation,and simulate the flowage topsy-turvydom inside the different oscillating tube structure.That provides the conditions for opening out the refrigeration mechanism.(2) By studying the tube wall temperature distributing of the straight oscillating tube, the results showed that:under the conditions of different parameters,the tube wall temperature distributing of the straight oscillating tube is rapidly rising first and then drops slowly along the tube length,the temperature at the end of the tube is lower,and the extent to heighten the temperature by changing the parameters is limited,in other word the utilization rate of the oscillating tube is lower and the it will become more lower when the jet flow frequency is changed,that resulting in a waste of the pipe material.(3) By studying the intersecting and transmission process of the pressure inside the oscillating tube,the result shows that the intersection of shock here can cause oscillation tube wall temperature rise,and it is good for dissipating the energy dissipation.Hereby,the Intersection Straight Oscillating Tube has been brought forward and the experiment and the numerical value analyse for it has been done.The result shows that the shock wave can intersect and permeate around the conterminous,and then the temperature at the department of the connection has been raised,in other words the utilization rate of the oscillating tube is increased.Simultaneity,the intension of the shock wave which return to the tube entrance has been weakened,and the isentropic refrigeration efficiency of the oscillating tube is improved; comparing with the straight oscillating tube,the isentropic refrigeration efficiency raises up to about 5%and the fluctuation range of isentropic refrigeration efficiency by the jet flow frequency is slightly decreased.(4) Basing on the structure characteristic of the Intersection Straight Oscillating Tube, and combining the mechanism of wreaking the intension of the reflected shock waves,the Intersection Damping Oscillating Tube has been proposed,and the experiment and the numerical value analyse for the influence of refrigeration capability by the diversified parameters has been done.The result shows that the reflected wave is expansion wave,that eliminates the adverse infection of the reflected shock waves.Comparing with the Straight Oscillating Tube,the isentropic refrigeration efficiency raises up to about 15%and the curve of the isentropic refrigeration efficiency becomes flat,that will improve the adaption ability of the Gas Wave Refrigerator.Simultaneity,in ensuring a higher isentropic efficiency of refrigeration,the length of the Intersection Damping Oscillating Tube has reduced significantly,therefore,the volume of the Gas Wave Refrigerator is reduced.

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CLC: > Industrial Technology > General industrial technology > Refrigeration Engineering > Refrigeration machinery and equipment > Refrigerator
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Study on Capability of Intersection Oscillating Tube

Abstract

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