摘要:

The method of snapshots for Karhunen–Loe`ve expansion has been applied to two‐dimensional, two‐component hot‐wire data from the first pairing region of a weakly perturbed free shear layer. Almost 90% of the fluctuation energy is captured by the first four modes. The first and the second modes contain almost equal amounts of energy, as do the third and the fourth, and the time dependence for each pair is very nearly sinusoidal with the odd modes leading in phase by &pgr;/2.

ISSN:0899-8213    

DOI:10.1063/1.857812

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

Theoretical and experimental knowledge of the bulk viscosity for a dilute gas is briefly reviewed. Neither area is satisfactory; the lack of experimental data for polyatomic gases over a broad temperature range is particularly acute. There is one circumstance where this deficiency is especially detrimental, namely, high‐speed entry into planetary atmospheres.

ISSN:0899-8213    

DOI:10.1063/1.857813

出版商:AIP    

年代:1990

数据来源: AIP