NASA STTR 2007 Solicitation


PROPOSAL NUMBER: 07-1 T2.02-9799
RESEARCH SUBTOPIC TITLE: Foundational Research for Aeronautics Experimental Capabilities
PROPOSAL TITLE: A Reusable, Oxidizer-Cooled, Hybrid Aerospike Rocket Motor for Flight Test

NAME: Rolling Hills Research Corporation NAME: Cal Poly Corporation
STREET: 420 N. Nash Street STREET: Building 15
CITY: El Segundo CITY: San Luis Obispo
STATE/ZIP: CA  90245 - 2822 STATE/ZIP: CA  93407 - 9000
PHONE: (310) 640-8781 PHONE: (805) 756-1123

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
William R Murray

Expected Technology Readiness Level (TRL) upon completion of contract: 3 to 4

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
The proposed innovation is to use the refrigerant capabilities of nitrous oxide (N2O) to provide the cooling required for reusable operation of an aerospike nozzle in conjunction with an N2O-HTPB† hybrid rocket motor. The phase change cooling as liquid N2O is flashed into a vapor is crucial to limiting to acceptable levels the erosion of both the nozzle throat and spike, thereby enabling reusable operation and/or long burn times. The N2O used for cooling the nozzle throat will be reintroduced into the combustion chamber, and the N2O used for cooling the spike will be used to provide base bleed, virtually eliminating any performance penalty associated with using a severely truncated, and therefore significantly lighter, spike. Because of its high vapor pressure, N2O can be self-pumping, thereby making it an ideal choice of oxidizer for simple, low-cost applications. As a simple, practical nozzle, the proposed innovation fits well with N2O-HTPB hybrid rocket designs, which tend toward simpler, less expensive design alternatives.
Because of their high efficiency due to altitude compensation, aerospike nozzles could play an important role in bringing to fruition inexpensive access to low Earth orbit. In addition, these altitude compensating nozzles could provide significantly increased performance for a wide array of tactical missiles. Although a few rocket flights powered by liquid propellant rocket engines and two flights powered by solid propellant rocket motors have used aerospike nozzles in the last several years, the lack of a comprehensive flight test database has precluded the use of these nozzles in current as well as next-generation space vehicles.
The simple, low-cost, reusable, oxidizer-cooled aerospike nozzle for operation on an N2O-HTPB hybrid rocket motor that is proposed herein is a device that will enable much-needed flight research of aerospike nozzles.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
At present no research other than our own is addressing thrust vectoring and throttling of the annular aerospike nozzle. Having a liquid oxidizer in a hybrid motor provides enhanced flexibility and safety compared to solid fuel propellants. The liquid oxidizer may be throttled back and forth, allowing for controlled thrust. In addition, according to our results, axial translation also can provide a measure of throttling. The two approaches, taken together, provide a means of continuous extreme throttling, allowing the possibility of in-flight shut-downs and restarts, thereby enhancing the flight envelope.
In the near term, aerospike nozzles with optimal thrust vector control would provide added safety and improved capability to the NASA Dryden Aerospike Rocket Test project, as well as economic benefit through the reuse of nozzles. Thrust vectoring and throttling capabilities would provide control of flight regimes (speed, angle of incidence, transients, and other flight conditions). In addition, flights with thrust vector control would have less dispersion and therefore could be confined to a smaller test area, which would improve range safety.
An aerospike nozzle with thrust vector control would be appropriate for future NASA single-stage-to-orbit programs.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The development of a cooled, truncated aerospike nozzle with an N2O-HTPB hybrid rocket motor will allow cost effective, reusable, and less expensive rocket designs. There are two major non-NASA customer groups for this technology: the U.S. military, and the numerous companies working to develop inexpensive low Earth orbit (LEO) launch vehicles. In addition to launching satellites into LEO, there has been increasing interest in developing space tourism in recent years. Scaled Composites and Virgin Galactic have teamed up to develop SpaceShipTwo specifically to pursue the space tourism market. Likewise, Benson Space Company is developing the Dream ChaserTM, which is a 4-passenger suborbital or 6-passenger orbital vehicle, both of which are based on NASA's HL-20 Personnel Launch System. Both versions of the Dream ChaserTM vehicle will use a hybrid rocket motor, an internal hybrid for the smaller vehicle or an internal hybrid plus an external hybrid booster for the larger vehicle.

NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.

Computational Materials
Launch Assist (Electromagnetic, Hot Gas and Pneumatic)
Launch and Flight Vehicle
Structural Modeling and Tools

Form Generated on 09-18-07 17:52