2009

Prediction of Launch Vehicle Ignition Overpressure and Liftoff Acoustics

The LAIOP (Launch Vehicle Ignition Overpressure and Liftoff Acoustic Environments) program predicts the external pressure environment generated during liftoff for a large variety of rocket types. These environments include ignition overpressure, produced by the rapid acceleration of exhaust gases during rocket-engine start transient, and launch acoustics, produced by turbulence in the rocket plume. The ignition overpressure predictions are time-based, and the launch acoustic predictions are frequency-based. Add itionally, the software can predict ignition overpressure mitigation, using water-spray injection into the rocket exhaust stream, for a limited number of configurations.

The framework developed for these predictions is extensive, though some options require additional relevant data and development time. Once these options are enabled, the already extensively capable code will be further enhanced.

The rockets, or launch vehicles, can either be elliptically or cylindrically shaped, and up to eight strap-on structures (boosters or tanks) are allowed. Up to four engines are allowed for the core launch vehicle, which can be of two different types. Also, two different sizes of strap-on structures can be used, and two different types of booster engines are allowed.

Both tabular and graphical presentations of the predicted environments at the selected locations can be reviewed by the user. The output includes summaries of rocket-engine operation, ignition overpressure time histories, and one-third octave sound pressure spectra of the predicted launch acoustics. Also, documentation is available to the user to help him or her understand the various aspects of the graphical user interface and the required input parameters.

This work was done by Matthew Casiano of Marshall Space Flight Center. For more information, contact Sammy Nabors, MSFC Commercialization Assistance Lead at This email address is being protected from spambots. You need JavaScript enabled to view it.. Refer to MFS-32579-1.

White Papers

R&S® SMB100A, NRP, FSW-K6, ZVL Radar Educational Videos
Sponsored by Rohde and Schwarz A and D
Reliability Testing of GORE® Protective Vents in LED Luminaires
Sponsored by Gore
Medical Capabilities Brochure
Sponsored by Nordson EFD
When Wire Feedthroughs Make Sense
Sponsored by Douglas Electrical Components
Thermally Conductive Epoxies Optimize Electronic Assemblies
Sponsored by Master Bond
6 Ways Software Rendering Boosts Embedded System Graphics
Sponsored by ENSCO Avionics

White Papers Sponsored By: