Sonic Boom Prediction of LowBoom Geometries
A spacetime CESE solver, ez4d developed by C.L. Chang at NASA LaRC, was used to obtain the following results
Cone cylinder geometry (Mach no. = 1.6, altitude = 45k ft, zero angle of attack)
Pressure disturbance contours

Comparison of pressure signature at h/L = 10

Ref.: Mendoza, J. P. and Hicks, R. M., “Further Studies of the Extrapolation of NearField Overpressure Data,” NASA TM X2219, 1971.
Quartic cone geometry (Mach no. = 1.6, altitude = 45k ft, zero angle of attack)
Ref.: Carlson, H. W., Mack, R. J., and Morris, O. A., “A Windtunnel Investigation of the Effect of Body Shape on Sonicboom Pressure Distribution,” NASA TN D3106, 1965.
Sonic Boom and Drag Mitigation of LowBoom Geometries using Counterflowing Jet
Conecylinder geometry
Geometry with counterflowing jet

Geometry and flow condition of counterflowing jet

Effect of counterflowing jet Mach number
Ratio of jet penetration length to jet diameter v.s. nozzle pressure ratio

Drag reduction percentage v.s. nozzle pressure ratio

Effect of counterflowing jet diameter
Effect of counterflowing jettobase diameter ratio
Ratio of jet penetration length to jet diameter v.s. nozzle pressure ratio

Drag reduction percentage v.s. nozzle pressure ratio

Numerical density gradient contours for diameter ratio of 1/8 at a nozzle total pressure of 11 atm
(click the picture for time animation)
(click the picture for time animation)
Numerical density gradient contours for diameter ratio of 1/16 at a nozzle total pressure of 11 atm
(click the picture for time animation)
(click the picture for time animation)
Quartic geoetry
Geometry with counterflowing jet

Geometry and flow condition of counterflowing jet

Comparison of density gradient contours for quartic geometry w/o counterflowing jet
Effect of counterflowing jettobase diameter ratio
Ratio of jet penetration length to jet diameter v.s. nozzle pressure ratio

Drag reduction percentage v.s. nozzle pressure ratio

Effect of counterflowing jet Mach number
Ratio of jet penetration length to jet diameter v.s. nozzle pressure ratio

Drag reduction percentage v.s. nozzle pressure ratio
