The interference phenomenon occurring when a subsonic turbulent jet exhausts normally from a large flat plate into a low speed crossflow was experimentally investigated in the Georgia Tech nine foot wind tunnel. Static pressures were measured on the surface around the jet. In the region off the surface, including the jet plume, wake and surrounding areas, the average total and static pressures and the average velocity magnitudes and directions were determined. Three jet exit configurations were studied, one circular and two slot-shaped with width to length ratios of 0.3 and 3.4. All have the same exit area. The effective jet to cross-flow velocity ratio was varied, for each of the exit configurations, over the range 4.0 to 12.0. Analysis of the data indicates that the pressure distributions induced on the surface are a combined result of the jet's blocking and entraining effects on the cross flow with entrainment becoming the more dominant of the two as the effective velocity ratio is increased. This relative dominance brings about an attenuation of total interference lift loss (when computed as a fraction of gross thrust) primarily by causing a rise in the low pressures in the wake region as the effective velocity ratio increases. When the effective velocity ratio is held fixed, the total interference lift loss increases with increasing width to length ratio of the jet exit. (Author).

Measurements have been made of the mean total-head and temperature fields in a round turbulent jet with various initial temperatures.

An investigation has been undertaken to develop a theoretical model of the incompressible jet injection process. The discharge of a turbulent jet into a cross flow was mathematically modeled by using an integral method which accounts for natural fluid mechanisms such as turbulence, entrainment, buoyancy, and heat transfer. The analytical results are supported by experimental data and demonstrate the usefulness of the theory for estimating the trajectory and flow properties of the jet for a variety of injection conditions. The capability of predicting jet flow properties, as well as two- and three- dimensional jet paths, was enhanced by obtaining the jet cross-sectional area during the solution of the conservation equations (a number of previous studies assume a specific growth for the area). Realistic estimates of temperature in the jet fluid were acquired by accounting for heat losses in the jet flow due to forced convection and to entrainment of free-stream fluid into the jet.