NASA SBIR 2004 Solicitation


SUBTOPIC TITLE:Revolutionary Materials and Structures Technology for Propulsion and Power Components
PROPOSAL TITLE:Physics-Based Probabilistic Design Tool with System-Level Reliability Constraint

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
N&R Engineering
6659 Pearl Road. #400
Parma Heights ,OH 44130 - 3821
(440) 845 - 7020

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Vinod   Nagpal
6659 Pearl Road. #400
Parma Heights, OH  44130 -3821
(440) 845 - 7020

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
The work proposed herein would develop a set of analytic methodologies and a computer tool suite enabling aerospace hardware designers to rapidly determine optimum risk-constrained designs subject to multiple physics-based uncertainties in applied loads, material properties, and manufacturing processes. This means that the design process no longer would consist of a sequence of separate code invocations to: (1) obtain the geometry model, (2) determine the various loads, (3) determine performance, (4) perform a structural analysis, (5) perform design optimization, and (6) perform a probabilistic risk assessment. Instead, all of these functions would be automatically incorporated into a single framework using existing physics-based deterministic modeling codes and a set of computer-generated data transfer interfaces. Thus, a design engineer would be able to rapidly explore the design space to identify the minimum weight design that meets a given reliability constraint ? thereby avoiding both an overly conservative design and an excessively risky design.

Moreover, the methodology would also rollup component-level uncertainties to the system level for multiple components -- thereby enabling a system level reliability constraint to be imposed at the component level. Advanced techniques will be developed including methods to: (a) determine confidence bounds on reliability predictions, (b) efficiently determine response surfaces, and (c) use physics-based progressive failure modeling. The software tool could be used, for example, to determine the wall thickness of a launch vehicle's external cryogenic propellant tanks exposed to high but uncertain thermal and aerodynamic loads with a reliability of 0.99999.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
A broad spectrum of design problems involving parts/subsystems/systems required to attain mission-critical reliability levels at minimum weight, yet subject to major technical uncertainties. These problems typically involve high temperature/high stress propulsion systems and range from single part designs such as novel CMC turbine blades used in advanced rocket engine turbopumps and jet engines to complete systems such as the unconventional propulsion concepts proposed for future space vehicles (e.g., nuclear thermal rockets, nuclear-electric, and solar-electric systems). These applications include conceptual designs where future technology status is uncertain as well as operational systems that experience variances in operating conditions and manufacturing fidelity.

The final product will be a suite of software tools that accelerate the design/analysis process, take the grunt work out of the typical engineering tasks of transferring/converting data streams from one application code to another, and capture the intrinsically probabilistic nature of design problems. This will enable engineers and managers to spend more of their time interpreting results and making wise decisions as well as yield a physics-based design-to-reliability solution.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
A fundamental architectural change in the design process is proposed that could revolutionize the way many commercial designs are conducted that involve advanced technology and important uncertainties. For example, high-tech applications such as nuclear-powered central powerplants, artificial hearts, flight-qualified control system actuators, home heat pumps/air conditioners, automotive engines, and avionic circuit boards all require ultra-reliable, minimal-maintenance operation. Some of these operate in uncertain hostile environments and all involve a continuous stream of technical improvements with inherent uncertainties. The software tool developed in this effort would accelerate these design processes while simultaneously yielding more reliable, cost-effective products.

Form Printed on 08-01-05 13:52