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Herring, H. J.

Publications and source records attributed to Herring, H. J..

Use of multiple discrete wall jets for delaying boundary layer separation

The effectiveness of a spanwise array of small discrete blowing nozzles in preventing separation of a turbulent boundary layer was investigated experimentally. The spacing, axial location, and momentum flux of the nozzles were varied in a systematic way, and overall performance was measured for each combination. Extensive mean velocity profiles were measured for one selected combination. Overall diffusion achieved before separation was correlated successfully with a momentum flux excess parameter, and in terms of this parameter discrete nozzles, when advantageously placed, were found to perform somewhat better than an optimally placed two-dimensional jet slot.

Mclean, J. D.↗

Discrete wall jets in quiescent air

An experimental investigation was made of turbulent jet flows resulting from small, round nozzles discharging parallel to a smooth, flat wall in quiescent air. Nozzle axes were located 3.0 nozzle diameters above the wall surface. The case of a single nozzle and the case of a spanwise array of equally spaced nozzles were investigated. Several forms of approximate velocity profile similarity were noted, and the flow from the array of nozzles was seen to approach the form of a two-dimensional wall jet.

Mclean, J. D.↗

Computer program for calculating laminar and turbulent boundary layer development in compressible flow

A computer program is described which performs a numerical integration of the equations of motion for a compressible two-dimensional boundary layer. Boundary layer calculations may be carried out for both laminar and turbulent flow for arbitrary Reynolds number and free stream Mach number distribution on planar or axisymmetric bodies with wall heating or cooling, longitudinal wall curvature, wall suction or blowing, and a rough or a smooth wall. A variety of options are available as initial conditions. The program can generate laminar initial conditions such as Falkner-Skan similarity solutions (so that initial wedge flows can be simulated including Blasius or stagnation point flow) or approximate equilibrium turbulent profiles. Alternatively, initial profile input data can be utilized.

Herring, H. J.↗

Computing incompressible laminar and turbulent boundary layer formation

Program generates initial laminar conditions, such as in Falkner-Skan similarity flows, or turbulent equilibrium profiles. Initial profile input data is used. Combination with inviscid-freestream calculations to predict entire flow field in turbine cascade or around airfoil is possible.

Herring, H. J.↗