The carreau-yasuda fluids: a skin friction equation for turbulent flow in pipes and kolmogorov dissipative scales

Autor: Jamilson A. Petronílio, D. O. A. Cruz, Luiz Claudio F. Andrade, Calos Edilson de A. Maneschy
Jazyk: angličtina
Rok vydání: 2007
Předmět:
Zdroj: Journal of the Brazilian Society of Mechanical Sciences and Engineering, Volume: 29, Issue: 2, Pages: 162-167, Published: JUN 2007
Journal of the Brazilian Society of Mechanical Sciences and Engineering v.29 n.2 2007
Journal of the Brazilian Society of Mechanical Sciences and Engineering
Associação Brasileira de Engenharia e Ciências Mecânicas (ABCM)
instacron:ABCM
Popis: In this work the turbulent flow of the Non-Newtonian Carreau-Yasuda fluid will be studied. A skin friction equation for the turbulent flow of Carreau-Yasuda fluids will be derived assuming a logarithmic behavior of the turbulent mean velocity for the near wall flow out of the viscous sub layer. An alternative near wall characteristic length scale which takes into account the effects of the relaxation time will be introduced. The characteristic length will be obtained through the analysis of viscous region near the wall. The results compared with experimental data obtained with Tylose (methyl hydroxil cellulose) solutions showing good agreement. The relations between scales integral and dissipative obtained for length, time, velocity, kinetic energy, and vorticity will be derived for this type of fluid. When the power law index approach to unity the relations reduces to newtonian case.
Databáze: OpenAIRE