Category
Applied
Description
This research investigates the use of computational fluid dynamics (CFD) to derive a coefficient-of-drag (Cd) profile for a high-powered rocket with an active airbrake control system to drive precise apogee control and trajectory prediction. High-fidelity CFD simulations are used to produce a reliable drag-coefficient function across relevant Mach numbers with airbrakes retracted and extended into the relative airstream, enabling more accurate trajectory modeling and control strategies for rockets employing aerodynamic drag modulation. This accurate drag characterization is critical as small deviations in the rocket’s Cd can significantly alter the predicted launch behavior and stability during high-powered flight. Prior work in aerospace analysis demonstrates that CFD methods, when supported by appropriate meshing strategies, turbulence models, and verification practices, can closely approximate experimental aerodynamic behavior for slender rocket geometries, but little to no research has been conducted to characterize drag modulation systems in subsonic rockets to apogees of 5,000-15,000ft. Preliminary results of this research yield Cd values for the rocket body with airbrakes retracted which are consistent with existing literature values, confirming the validity of the meshing and simulation approach and validating the accuracy of new results found for the Cd with airbrakes extended. A mathematical expression can then be derived for the Cd as a function of the rocket Mach number with airbrakes extended and retracted by interpolating between the resulting data points. This Cd curve can then be incorporated into rocket trajectory simulation environments to analyze the influence of airbrake drag modulation on rocket performance and support apogee control strategies in real rocket systems. The results of this work have broad implications in the aerospace field, as accurate CFD-derived drag models can improve trajectory prediction, aerodynamic design, and flight-control strategies for high-powered and sounding rockets to improve flight simulation and active flight control.
Aerodynamic Performance Analysis of High-Powered Rocket Airbrakes
Applied
This research investigates the use of computational fluid dynamics (CFD) to derive a coefficient-of-drag (Cd) profile for a high-powered rocket with an active airbrake control system to drive precise apogee control and trajectory prediction. High-fidelity CFD simulations are used to produce a reliable drag-coefficient function across relevant Mach numbers with airbrakes retracted and extended into the relative airstream, enabling more accurate trajectory modeling and control strategies for rockets employing aerodynamic drag modulation. This accurate drag characterization is critical as small deviations in the rocket’s Cd can significantly alter the predicted launch behavior and stability during high-powered flight. Prior work in aerospace analysis demonstrates that CFD methods, when supported by appropriate meshing strategies, turbulence models, and verification practices, can closely approximate experimental aerodynamic behavior for slender rocket geometries, but little to no research has been conducted to characterize drag modulation systems in subsonic rockets to apogees of 5,000-15,000ft. Preliminary results of this research yield Cd values for the rocket body with airbrakes retracted which are consistent with existing literature values, confirming the validity of the meshing and simulation approach and validating the accuracy of new results found for the Cd with airbrakes extended. A mathematical expression can then be derived for the Cd as a function of the rocket Mach number with airbrakes extended and retracted by interpolating between the resulting data points. This Cd curve can then be incorporated into rocket trajectory simulation environments to analyze the influence of airbrake drag modulation on rocket performance and support apogee control strategies in real rocket systems. The results of this work have broad implications in the aerospace field, as accurate CFD-derived drag models can improve trajectory prediction, aerodynamic design, and flight-control strategies for high-powered and sounding rockets to improve flight simulation and active flight control.
