DEVIATION OF GASEOUS HELIUM PROPERTIES FROM AN IDEAL GAS EQUATION

For the purpose to develop industry, from new potential mineral or substances, Indonesia needs the equation of state or the ideal gas formulation to simplify the thermodynamic design problem solving analytically or computationally to produce newly advanced, superior products.To build up P-V-T data, many references and experimental data are needed, such as specific heat, the speed of sound, and many others. An approximate mathematical model is required to produce analytical results, analytically, computationally. In most concept, the use of simplified equations, such an ideal gas, is preferable, especially during the employment of the perturbation method, numerical techniques to produce new superior products.In this paper some results of ideal gas model deviation would be presented, especially helium for a wide range of pressure up to 108 Pa and a wide range of temperature, 2 K to 1500 K. In this extensive region, gaseous helium behaves as an ideal gas, one can expect that the specific heat of constant volume is Cv =3/2 R =3.118 J/g K. There arevast region in space where ideal gas and constant Prandtl number assumptions can be used to approximate the thermophysical properties of gaseous helium.