Parametric method for use in periodicboundarylayer theory at large Strouhal numbers
Abstract
A parametric method proposed by Loitsianskii (1973) for calculating steady laminar boundary layers is extended to include unsteady boundary layers whose velocity at the outer edge varies in time according to a periodic law. To this end, Linn's (1957) equation describing the motion in boundary layers with a rapidly oscillating external flow are reduced (with the aid of specially selected parameters) to a universal form that is independent of the characteristics of the oscillating external flow. Some qualitative conclusions on the influence of the oscillating external flow are drawn from the results of integration (in a local threeparameter approximation) of the universal equation. The results can be used also for approximate solution of problems with a given velocity distribution in the external flow.
 Publication:

Inzhenerno Fizicheskii Zhurnal
 Pub Date:
 January 1976
 Bibcode:
 1976InFiZ..30...96B
 Keywords:

 Boundary Layer Stability;
 Laminar Boundary Layer;
 Oscillating Flow;
 Unsteady Flow;
 Boundary Layer Equations;
 Differential Equations;
 Flow Velocity;
 Strouhal Number;
 Fluid Mechanics and Heat Transfer