The Experts below are selected from a list of 6 Experts worldwide ranked by ideXlab platform

Felix Sharipov - One of the best experts on this subject based on the ideXlab platform.

  • Sound propagation through a rarefied gas confined between source and receptor at arbitrary Knudsen number and sound frequency
    Physics of Fluids, 2009
    Co-Authors: Denize Kalempa, Felix Sharipov
    Abstract:

    A sound propagation through a rarefied gas is investigated on the basis of the linearized kinetic equation taking into account the influence of receptor. A Plate oscillating in the normal direction to its own plane is considered as a sound source, while a Stationary Parallel Plate is considered as being the receptor of sound. The main parameters determining the solution of the problem are the oscillation speed parameter, which is defined as the ratio of intermolecular collision frequency to the sound frequency, and the rarefaction parameter defined as the ratio of the distance between source and receptor to the molecular mean free path. The kinetic equation is solved via a discrete velocity method with a numerical error of 0.1%. The numerical calculations are carried out for wide ranges of the oscillation and rarefaction parameters. The concept of integral phase parameter is introduced to obtain the sound speed correctly in all regimes of the gas rarefaction and sound frequency. Analytical solutions are obtained in the limits of small and large parameters of frequency and rarefaction.

Denize Kalempa - One of the best experts on this subject based on the ideXlab platform.

  • Sound propagation through a rarefied gas confined between source and receptor at arbitrary Knudsen number and sound frequency
    Physics of Fluids, 2009
    Co-Authors: Denize Kalempa, Felix Sharipov
    Abstract:

    A sound propagation through a rarefied gas is investigated on the basis of the linearized kinetic equation taking into account the influence of receptor. A Plate oscillating in the normal direction to its own plane is considered as a sound source, while a Stationary Parallel Plate is considered as being the receptor of sound. The main parameters determining the solution of the problem are the oscillation speed parameter, which is defined as the ratio of intermolecular collision frequency to the sound frequency, and the rarefaction parameter defined as the ratio of the distance between source and receptor to the molecular mean free path. The kinetic equation is solved via a discrete velocity method with a numerical error of 0.1%. The numerical calculations are carried out for wide ranges of the oscillation and rarefaction parameters. The concept of integral phase parameter is introduced to obtain the sound speed correctly in all regimes of the gas rarefaction and sound frequency. Analytical solutions are obtained in the limits of small and large parameters of frequency and rarefaction.

Thomas J. Hofler - One of the best experts on this subject based on the ideXlab platform.

  • Theoretical study of heat transport in thermoacoustic stacks having arbitrary Plate separation.
    The Journal of the Acoustical Society of America, 1992
    Co-Authors: Thomas J. Hofler
    Abstract:

    Thermoacoustic heat engines can be simply described as devices where heat transport is caused by the interaction between a standing wave and a Stationary, Parallel Plate structure called the stack. Simplified calculations of this heat transport have been discussed previously, which assume perfect standing waves (infinite standing wave ratio) and Plate separations that are large relative to a thermal penetration depth. A theory will be presented that is generalized to describe systems with arbitrary Plate separation and SWR. Using this theory, the spectrum of heat engine designs that span ‘‘classic’’ thermoacoustic engines on the one extreme, and Stirling cycle engines on the other extreme, can be compared. Some results are that Stirling cycle engines can be more efficient than standard thermoacoustic engines and that, given some practical constraints, thermoacoustic engines can deliver more power than a comparable Stirling engine. Other results may help to design an improved engine that combines the chara...