Cryogenics (Helium Liquefaction)

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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 04 Issue: 04 | Apr -2017

p-ISSN: 2395-0072

www.irjet.net

Cryogenics (Helium Liquefaction) Gagandeep Singh1, Er. Jasvinder Singh2, Er. Jagdish Singh3, Amandeep Singh4 1Student,

Department of Mechanical Engineering, DIET, Kharar

2Assistant

Professor, Department of Mechanical Engineering, DIET, Kharar

3Assistant

Professor, Department of Mechanical Engineering, DIET, Kharar

4Scientific

Assistant C, Pelletron LINAC Facility, TIFR, Mumbai

---------------------------------------------------------------------***--------------------------------------------------------------------Table No.1:

Abstract- This paper represents process for liquefaction of

Cryogen fluids and refrigeration fluids boiling temperature

helium. Helium becomes liquid at cryogenic temperature so this paper includes the study of cryogenics. Liquefaction of gases is physical conversion of a gas into a liquid state (condensation). We all are familiar with the different phases of matter viz. gas, liquid and solid. The basic difference between these phases is the strength of intermolecular attraction between their molecules. By changing the strength of intermolecular attraction between molecules of any phase we can transform it to another phase. By reducing volume of gases we can change their phase. Most of the gases becomes liquid below -150 ℃ e.g. Helium, nitrogen, oxygen etc. In physics production or working with these super cold temperatures (below -150 ℃) is known as ‘Cryogenics’. Liquefaction is used for analyzing the fundamental properties of gas molecules (intermolecular forces), for storage of gases, heat treatment, superconductivity, used as cryogenic fuel, food industry and used in medical science. The conclusion tells us about the liquefaction of gases and their advantages in today’s world. Helium liquefier, Heat exchangers, Turbine, Vacuum pumps, JT expansion.

1. INTRODUCTION

Impact Factor value: 5.181

O2 (90.19 K)

R134a (246.8 K)

Air(78.6 K)

R12 (243.3 K)

N2 (77.36 K)

R22 (233 K)

H2 (20.39 K)

Propane (231.1 K)

He (4.2 K)

Ethane (184 K)

A) By compressing the gas at temperatures less than its critical temperature.

Cryogenics is the science and technology associated with generation of low temperature below 123 K or -150 degree Celsius. Cryogenics come from the two words Kryo means” very cold (frost)” and Genics means “To produce”. So its “Science and art of producing very cold”. Difference between cryogenics and refrigeration fluids are shown in table-1. Cryogenic liquids are used for accessing low temperatures. They are extremely cold, with boiling points below 123K. Carbon dioxide and nitrous oxide, which have slightly higher boiling points, are sometimes included in this category.

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Refrigeration

The liquefaction of gases was first carried out by the English scientist Michael Faraday (1791-1867) in the early 1820s. There are three methods to liquefy gases. These are given below:-

Keywords-

© 2017, IRJET

Cryogenics

B)

By making the gas do some kind of work against an external force, causing the gas to lose energy and change to the liquid state.

C) By making gas do work against its own internal forces, also causing it to lose energy and liquefy. Many gases can be put into a liquid state at normal an atmospheric temperature by simple cooling; a few, such as CO2, require pressurization as well. There are two most important factors needs to be achieved for liquefaction critical temperature and pressure. The critical temperature of a substance is the temperature at and above which vapour of the substance cannot be liquefied, no matter how much pressure is applied .Every substance has a critical

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