Lagrangian statistics of pressure fluctuation events in homogeneous isotropic turbulence

Autor(es)

Bappy, Mehedi ^[1] ; Carrica, Pablo M. ^[1] ; Buscaglia, Gustavo C. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Iowa, IIHR Hydrosci & Engn, Iowa City, IA 52242 - USA

^[2] Univ Sao Paulo, Inst Ciencias Matemat & Comp, Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Physics of Fluids; v. 31, n. 8 AUG 2019.
• Citações Web of Science: 0

Resumo

Homogeneous and isotropic turbulent fields obtained from two direct numerical simulation databases (with Re-lambda equal to 150 and 418) were seeded with point particles that moved with the local fluid velocity to obtain Lagrangian pressure histories. Motivated by cavitation inception modeling, the statistics of events in which such particles undergo low-pressure fluctuations were computed, parameterized by the amplitude of the fluctuations and by their duration. The main results are the average frequencies of these events and the probabilistic distribution of their duration, which are of predictive value. A connection is also established between these average frequencies and the pressure probability density function, thus justifying experimental methods proposed in the literature. Further analyses of the data show that the occurrence of very-low-pressure events is highly intermittent and is associated with wormlike vortical structures of length comparable to the integral scale of the flow. Published under license by AIP Publishing. (AU)

• Processo FAPESP: 18/08752-5 - Modelagem numérica avançada de escoamentos multifásicos
• Beneficiário: Gustavo Carlos Buscaglia
• Linha de fomento: Bolsas no Exterior - Pesquisa