A modification of the values of three constants C1, C2 and C3 in the standard K-ε turbulence model is proposed, based on the empirical law of decay obtained for nearly homogeneous in-cylinder turbulence. Since the decay exponent of Reynolds numbers for in-cylinder turbulence is found to be different from that for steady ducted flow just behind a turbulence-generating grid, the C2 value is modified first, followed by the C1 and C3 values, which depend on the C2 value. The derived C2 value of 1.40 is smaller than that in the standard K-ε turbulence model, but the C1 value, 1.40 is close to that of the standard one. The C3 value, -1.05, is very close to the recommended value by Morel et al. for the case of a unidirectional axial compression.
|ジャーナル||JSME International Journal, Series B: Fluids and Thermal Engineering|
|出版ステータス||出版済み - 2 1 1989|
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