Accession Number : AD0717643

Title :   Radiatively Driven Acoustic Waves in a Gas in a Cylindrical Tube--Theory and Experiment for the Untuned Condition.

Descriptive Note : Technical rept.,

Corporate Author : STANFORD UNIV CALIF DEPT OF AERONAUTICS AND ASTRONAUTICS

Personal Author(s) : Chapman,Gary T.

Report Date : AUG 1970

Pagination or Media Count : 240

Abstract : A detailed theoretical and experimental study of radiatively driven acoustic waves in a closed cylindrical tube has been made. The study concerns itself primarily with conditions for vibrational equilibrium of the gas and for the untuned conditions of the wave tube. The theoretical treatment considers all of the essential elements of the problem such as gas motion, longitudinal and radial heat conduction, longitudinal and radial viscous dissipation, and radiation including spectral details. In the light of this theoretical treatment some existing spectrophone data are then analyzed. These data are for conditions where the wave tube is much smaller than an acoustic wave. There is good agreement of basic trends; absolute values could not be compared. Tests are then described in which the absolute pressure level as well as the input radiation were measured. These tests were conducted in a wave tube 75-cm long by 10-cm in diameter. Some of the various test conditions were: Gas mixtures of CO2 and CO in argon, gas temperatures of 300K and 600K, wave numbers of 1/4, 3/4, and 5/4, and three different levels of input radiation. The general agreement between the results of these tests and theory was fairly good on both an absolute basis as well as with trends. Most of the areas of disagreement were traceable to two sources; nonisotropy of the input radiant energy and the use of frequency-averaged absorption coefficients. (Author)

Descriptors :   (*GAS FLOW, SOUND TRANSMISSION), (*GASES, THERMAL RADIATION), VISCOSITY, TRANSPORT PROPERTIES, PARTIAL DIFFERENTIAL EQUATIONS, INFRARED RADIATION, BOUNDARY LAYER, TRANSFER FUNCTIONS, INTEGRALS, NUMERICAL INTEGRATION, DAMPING, SPECTRUM ANALYZERS, CARBON DIOXIDE, CARBON MONOXIDE, ARGON

Subject Categories : Acoustics
      Fluid Mechanics
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE