LOCAL AND INTEGRAL VALUES OF COEFFICIENTSOF THE TURBULENT VELOCITY PROFILE
Pages 201-208
The authors study velocity profiles of turbulent fluid flows, if their cross sections have different shapes. The research is performed using the Karman constant value equal to0.4 and a local parameter of the variable along the velocity profile. An experimentally obtained value of the Karman constant is treated as an integral parameter describing the inclination angle of the velocity profile being constant within the turbulent flow core. In turn, the local parameter describes the local inclination angle of the velocity profile. The authors demonstrate that the local parameter calculated on the basis of maximal and average flow velocities does not relate to the Karman constant, and therefore, it cannotbe used for its validation. The local coefficient can be considered as a supplementary characteristic of the turbulent flow profile. The local parameter and its distribution over the cross section of the flow can be used to clarify the law of resistance, obtained by using the assumption that the Karman constant value is equal to 0.4. Availability of the value of the local parameter distribution over the cross section of the flow may be used to clarify the alteration pattern of the turbulent structure of the flow. Areas of application of both values are also identified.
DOI: 10.22227/1997-0935.2013.4.201-208
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