James R. Forsythe

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Cross-sectional echocardiography is a new noninvasive technique for imaging the heart. We developed a method for using mechanical cross-sectional echocardiograms (sector scans) to determine left ventricular volumes and ejection fraction. Using left ventricular cineangiography as a standard, sector scan ejection fraction correlated better (r = 0.93) than(More)
Detached-eddy simulation is applied to an axisymmetric base flow at supersonic conditions. Detached-eddy simulation is a hybrid approach to modeling turbulence that combines the best features of the Reynolds-averaged Navier-Stokes and large-eddy simulation approaches. In the Reynolds-averaged mode, the model is currently based on either the Spalart-Allmaras(More)
The flowfield around a 6:1 prolate spheroid at angle of attack is predicted using solutions of the Reynolds-averaged Navier-Stokes (RANS) equations and detached-eddy simulation (DES). The calculations were performed at a Reynolds number of 4.2ϫ10 6 , the flow is tripped at x/Lϭ0.2, and the angle of attack ␣ is varied from 10 to 20 deg. RANS calculations are(More)
Predictions of the massively separated flow around a rectangular ogive forebody are obtained using Detached-Eddy Simulation (DES) and solutions of the unsteady Reynolds-averaged Navier-Stokes (URANS) equations. Based on the body width/diameter D, the forebody length is 2D while the length of the aft section is 4D. The cross-section is a rounded-corner(More)
Predictions of the flow over a wall-mounted hump are obtained using solutions of the Reynolds-averaged Navier-Stokes (RANS) equations and Detached-Eddy Simulation (DES). The upstream solution is characterized by a two-dimensional turbulent boundary layer with a thickness approximately half of the maximum hump thickness measured at a location about two chord(More)
A successful fielding of computation-based engineering (CBE) software requires quality assurance to be built into the fabric of capability development and deployment processes. Good software quality is an emergent property of the healthy interplay among CBE software development teams, testing teams, user support, and training teams, with the vital notion of(More)
Aircraft aerodynamics have been predicted using computational fluid dynamics for a number of years. While viscous flow computations for cruise conditions have become commonplace, the non-linear effects that take place at high angles of attack are much more difficult to predict. A variety of difficulties arise when performing these computations, including(More)
Detached-Eddy Simulation (DES) is used to predict the flow over an axisymmetric cavity. The freestream Mach number is 0.4, the length-to-depth ratio of the cavity is equal to five. The main objectives are to characterize the instantaneous and mean properties of the solution, with a focus on the application of adaptive mesh refinement for improving the(More)
Prediction of the time-dependent flow around a 6 : 1 prolate spheroid undergoing a pitchup maneuver were obtained using Detached-Eddy Simulation (DES). The spheroid pitches about its centroid from 0 • to 30 • angle of attack at a dimensionless rate of 0.047 (based on the freestream speed and model length). Flowfield predictions are evaluated using(More)