A KINETIC THEORY DESCRIPTION OF RAREFIED GAS FLOWS. Memorandum Report No. 51

Technical Report · Tue Dec 15 04:00:00 EST 1959

OSTI ID:4181935

Lees, L

An approach to the kinetic theory of gas flows is developed which starts with Maxwell's original integral equations of transfer, rather than with the Maxwell-Boltzmann equation for the velocity distribution function itself. In this procedure the Maxwell-Boltzmann equation is satisfied in a certain average sense, rather than at every point. The advantage of this method is that relatively simple distribution functions are utilized which contain a small number of unknown functions to be determined by applying the conservation laws, plus several additional higher moments. For simplicity a "two-stream Maxwellian" is employed, which is a natural extension and generalization of Mott-Smith's function for a normal shock, but differs from it in certain essential respects. As an illustration, the method is applied to linearized plane Couette flow and Rayleigh's problem. Reasonable results are obtained for macroscopic quantities such as mean velocity and shear stress over the whole range of densities from free-molecule flow to the Navier-Stokes regime. This technique is now being applied to some typical non-linear rarefied gas flows. (auth)

• Research Organization: California Inst. of Tech., Pasadena. Guggenheim Aeronautical Lab.
• NSA Number: NSA-14-010575
• OSTI ID: 4181935
• Report Number(s): NP-8424
• Country of Publication: United States
• Language: English

Related Subjects

BOLTZMANN STATISTICS
COUETTE FLOW
DENSITY
DIFFERENTIAL EQUATIONS
DIFFUSION
DISTRIBUTION
EFFICIENCY
ELECTROMAGNETISM
ENGINEERING AND EQUIPMENT
FLUID FLOW
GAS FLOW
GASES
IMPACT SHOCK
KNUDSEN EFFUSION
MAXWELL EQUATIONS
MECHANICS
NAVIER- STOKES EQUATIONS
RAREFIED GASES
RAYLEIGH NUMBER
STRESSES
TRANSFER FUNCTIONS
VELOCITY
VISCOSITY