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Kinetic Theory
hi
In the ideal gas model using the kinetic theory for Cp and K, which are the values to insert in degrees of freedom........... thanks in advance payment |

Re: Kinetic Theory
Hi,
the number of translational and rotational modes are added up. For monatomic gasses this is 3 for diatomic this is 5 ie 3 translations and 2 rotations. Cv=DOF/2*R/M Cp=(DOF+2)/2*R/M R=universal Gas Constant 8.314[kJ/kg/K] M=mollecular Weight [kg/kmol] So let us try this for Argon, DOF=3, M=39.94[kg/kmol] Plug it in and get 0.527[kJ/kg/K] compare to Reynold's and Perkins, "Engineering Thermodynamics" talbe B-6b 0.523[kJ/kg/K] Similarly k=Cp/Cv=3/5=1.67 Try it out for nitrogen and oxygen and you will get pretty good comparison as well, ie k=1.4! So as a first approximation it works quite well for monatomic and diatomic gasses. Regards, BAK_FLOW |

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