The Vuilleumier cryocooler is a heat engine which uses heat energy rather for the machine, and detailes of design based an isothermal thermodynamic cycle. PDF | A detailed experimental results of one-stage VM cryocooler with Experimental study on a one-stage Vuilleumier cryocooler with large pressure ratio VM-PT cryocooler can be designed in several configurations. Download Citation on ResearchGate | Study of a Vuilleumier cycle cryogenic This effort led to the selection of an optimum refrigerator design for the LSIR the feasibility of using a Vuilleumier cryocooler to cool a flight-type detector .
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It leaves the heat exchanger at room temperature desing a. A more detailed description of Joule-Thomson coolers and Joule-Thomson refrigerators can be found in .
February 25, received: A regenerator consists of a matrix of a solid porous material, such as granular particles or metal sieves, through which gas flows back and forth.
Note that even a perfect heat exchanger will not affect the entrance temperature T i of the gas. The cycle starts with the low-pressure lp valve closed, the high-pressure hp valve open, and the displacer all the way vuilpeumier the right so in the cold region. They provide stiffness in the radial direction and flexibility in the axial direction.
It is used to cool some particular application to cryogenic temperatures. Transactions of the Japan Society of Mechanical Engineers.
Cryocooler – Wikipedia
The Vuilleumier cryocooler is a heat engine which uses heat energy rather than mechanical energy to cyclically pressurize the working gas. The cooler operates at a frequency near the resonance frequency of the mass-spring system of the cold finger. The compression heat is removed by cooling water. The liquid fraction is x.
February 17, Released: This leads to losses. In the pV diagram O. The work, performed during the expansion, is used to reduce the total input power. In this way the efficiency is improved and the high pressure is much lower than bar.
The volume V is the volume between the two pistons. An important component of refrigerators, operating with oscillatory flows, is the regenerator.
Dseign the gas is at room temperature. The pistons and the compressor casing don’t touch so no lubricants are needed and there is no wear. Periodically heat is stored and released by the material. Typically its motion is 90 degrees out of phase with the piston. The heat contact with the gas must be good and the flow resistance of the matrix must be low.
Gifford-McMahon GM coolers  have found widespread application in many low-temperature systems e. The regenerator in the cold finger is suspended by a spring. Its position is synchronized with the motion of the displacer. In order to keep the system in the steady state gas is supplied to compensate for the liquid fraction x that has been removed. No work is required to move the displacer since, ideally there is no pressure drop over it. Previous article Next article. This paper describes the specifications required for the machine, and detailes of design based an isothermal thermodynamic cycle.
Usually the regenerator and the displacer are combined in one body. It leaves the exchanger at point c. Journal home Journal issue About the journal. From left to right it consists of: The pressure variations in the cold head are obtained by connecting it periodically to the high- and low-pressure sides of a compressor by a rotating valve.
One must also prevent oil vapor from entering the regenerator by high-quality purification traps. Next it enters the warm high-pressure side of the counterflow heat exchanger where it is precooled. The liquid leaves the system at the bottom of the reservoir point e and the gas fraction 1- x flows into the cold low-pressure side of the counterflow heat exchanger point f. In this way the swept volume of the compressor can be 50 60 times smaller than of the cooler.
The thermodynamic and hydrodynamic properties of regenerators are very complicated, so one usually makes simplifying models. Left and right the thermal contact with the surroundings at the temperatures T a and T L is supposed to be perfect so that the compression and expansion are isothermal.