In this paper the comparison between two different numerical approaches for sonic boom evaluation is presented: one is based on the Carlson method, the other is based on CFD computations and both are aimed to evaluate the ground signature due to a supersonic flight. The Carlson’s method is a simplified method for the calculation of sonic-boom characteristics for a wide variety of supersonic airplane configurations and spacecraft operating at altitudes up to 76 km. Sonic-boom overpressures and signature duration may be predicted for the entire affected ground area for vehicles in level flight or in moderate climbing or descending flight paths and the prediction requires in input the geometry of airplane and the operative conditions. A classical, more general approach for the sonic boom analysis is based on solution of the aerodynamic field in the vicinity of the aircraft, evaluation of the pressure disturbance far field propagation and prediction of the ground acoustic signature from the effective sonic boom perceived annoyance. These two methods have been used for sonic boom evaluation on a conventional reference supersonic geometry: the ground signature has been obtained and the comparison has shown a reasonable numerical agreement under some physical conditions. The paper shows the technical aspects of two before mentioned different approaches with special regard to the computational effort needed, low for the simplified Carlson’s method, high for CFD approach, and the numerical reliability of the solution.
Numerical comparison between a simplified method and a full CFD approach for sonic boom evaluation on supersonic innovative configurations
SCARSELLI, Gennaro;
2007-01-01
Abstract
In this paper the comparison between two different numerical approaches for sonic boom evaluation is presented: one is based on the Carlson method, the other is based on CFD computations and both are aimed to evaluate the ground signature due to a supersonic flight. The Carlson’s method is a simplified method for the calculation of sonic-boom characteristics for a wide variety of supersonic airplane configurations and spacecraft operating at altitudes up to 76 km. Sonic-boom overpressures and signature duration may be predicted for the entire affected ground area for vehicles in level flight or in moderate climbing or descending flight paths and the prediction requires in input the geometry of airplane and the operative conditions. A classical, more general approach for the sonic boom analysis is based on solution of the aerodynamic field in the vicinity of the aircraft, evaluation of the pressure disturbance far field propagation and prediction of the ground acoustic signature from the effective sonic boom perceived annoyance. These two methods have been used for sonic boom evaluation on a conventional reference supersonic geometry: the ground signature has been obtained and the comparison has shown a reasonable numerical agreement under some physical conditions. The paper shows the technical aspects of two before mentioned different approaches with special regard to the computational effort needed, low for the simplified Carlson’s method, high for CFD approach, and the numerical reliability of the solution.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
