Author:
Jaluria Yogesh,Gebhart Benjamin
Abstract
An experimental investigation has been made of the processes occurring during the natural transition from laminar to turbulent flow of natural convection flow of water adjacent to a flat vertical surface where the surface heat flux is uniform. Measurements of both the velocity and temperature fields were made over wide ranges of the heat flux and at various downstream locations. Of principal interest were the definitions of the boundaries of the transition regime and their determination at several values of the surface heat flux. The interaction of the velocity and temperature fields during transition was measured. Our results show that transition events are not correlated in terms of the Grashof numberG*. The formG*/xn, wherenis of order ½ was found to give satisfactory correlations. Measurements of the frequency and growth rate of disturbances indicate the primacy of the velocity field during transition and show that the growth of turbulence in the temperature field lags behind that in the velocity field. The study of the turbulence growth, in terms of intermittency factors in both the velocity and temperature fields, resulted in unambiguous criteria for the boundaries of the transition regime. Our results suggest a kinetic energy flux parameterEand a single value closely correlates both our measurements of the onset of transition as well as those from all past studies known to us, for both different fluids and heating conditions.
Publisher
Cambridge University Press (CUP)
Subject
Mechanical Engineering,Mechanics of Materials,Condensed Matter Physics
Reference25 articles.
1. Gebhart, B. 1969 Natural convection flow, instability and transition J. Heat Transfer,91,293.
2. Polymeropoulos, C. E. 1966 A study of the stability of free convection flow over a uniform flux plate in nitrogen. Ph.D. thesis, Cornell University. (See also Polymeropoulos, C. E. & Gebhart, B. 1967 Incipient instability in free convection laminar boundary layers J. Fluid Mech. 30,225.)
3. Colak-Antic, P. 1964 Hitzdraht messungen des Laminar-Turbulenten Umschlags bei freier Konvektion. In Jahrbuch der WGLR ,p.172.
4. Godaux, F. & Gebhart, B. 1974 An experimental study of the transition of natural convection flow adjacent to a vertical surface Int. J. Heat Mass Transfer,17,93.
5. Jaluria, Y. 1972 The growth and propagation of three-dimensional disturbances in laminar natural convection flow adjacent to a flat vertical surface. M.S. thesis,Cornell University.
Cited by
71 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献