• DEVENDRA SINGH
• AKHLESH KUMAR SHAKYA

Pulse tube cryocooler (PTC) is a small-scale refrigerator capable of attaining cryogenic temperature below 123K. With deep study, the main advantages of this system is their no moving part at low temperature as well as its simplicity, low cost, low vibration at cold head and long life time. The performance of the Pulse tube cryocooler, has been especially adopted in operations like aerospace, infrared sensors, communication, night vision equipment, cryo-pumping, SQUID and superconductivity. In this, the present paper is classified into two groups which are discussed below. In the first part of the paper, Evaluate study of single stage coaxial as well as inline Inertance-Type Pulse Tube Refrigerator (ITPTR), whose performance depends on a regenerator. The regenerator is the important component of a pulse tube refrigerator which has a great significance of producing a cooling effect. In this present work a computational fluid dynamic (CFD) solution advance has been chosen for numerical purpose. The detail analysis of cool down behavior, heat transfer at the cold end and change in pressure the whole system has been carried out by using the commercially available computational fluid dynamic software package FLUENT. A number of cases have been solved by changing the porosity of the regenerator from 0.4 to 0.8 and the rest of variables remains constants. The operating frequency in all cases is 32 Hz, pulse tube diameter 7mm and length is 130mm. The result shows that a porosity value of 0.7 produces a better cooling effect on the cold end of the pulse tube refrigerator. The change of pressure inside the pulse tube refrigerator during the process also investigates. In the second part of paper, a new modeling approach for the performance of a pulse tube refrigerator is projected. A single stage Stirling type diaphragm type pulse tube refrigerator is considered for CFD simulation using Fluent software. The two-dimensional geometry is taken for simulation. In this simulation the physical dimensions of all the components are kept constant and pressure input is generated from the different User Defined Function for compressor and diaphragm. Generally, DC gas flow in pulse tube refrigerator created a major problem at the time of investigation, which will affect the cooling down performance because DC gas flow carries heat away from the HHX and deposits at the cold end reading an additional heat loss and unwanted thermal load to CHX , which degrades the cooling performance and doctorates the refrigeration stability of pulse tube cryocooler. For obtaining better temperature stability at CHX end, suppress the DC flow by eliminating the closed loop by using a diaphragm in between HHX and orifice valve. This simulation starts with an assumed uniform system temperature, and continued until steady periodic conditions are achieved by varying the pressure amplitude and getting the better stabilization temperature. The result shows that amplitude of 0.0045 produces a better cooling effect on the cold end of the pulse tube refrigerator.

REFRIGERTOR,CRYOGENIC,CRYPCOOLER,COOLONG EFFECT,POROSITY,FLUENT SOFTWARE

"Tentative Analysis of Pulse Tube Refrigerator", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.5, Issue 12, page no.588-598, December-2018, Available :http://www.jetir.org/papers/JETIR1812B74.pdf

"Tentative Analysis of Pulse Tube Refrigerator", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.5, Issue 12, page no. pp588-598, December-2018, Available at : http://www.jetir.org/papers/JETIR1812B74.pdf