Computerized Study of Finite‐Amplitude Standing Waves in a Duct

Autor: Paul G. Ruff, Alan B. Coppens
Rok vydání: 1971
Předmět:
Zdroj: The Journal of the Acoustical Society of America. 50:125-125
ISSN: 0001-4966
DOI: 10.1121/1.1977558
Popis: A one‐dimensional model of a finite‐amplitude standing wave confined to a duct (wherein boundary‐layer effects at the walls produce energy losses greater than those arising from viscous and thermal effects in the body of the fluid) has been established. The resultant set of coupled nonlinear equations can be solved either by a perturbation technique or by assuming a Fourier superposition of standing waves. The perturbation solution has been performed through sixth order and reveals the poor convergence properties of this approach. The Fourier superposition results in an infinite set of coupled nonlinear algebraic equations which can be solved by successive approximations with the help of a digital computer. Results have been obtained for Mb/δ1 below 0.75 and −1.0⩽2Δω/ωrδ1⩽2.0, where M is a Mach number, b = (γ+1)/2, γ is the ratio of specific heats of the gas, α1 = δ1ω/2c0, α1 is the absorption coefficient for the fundamental component of the standing wave in the infinitesimal amplitude limit, ω is the ang...
Databáze: OpenAIRE