NASA 1998 SBIR Phase I


PROPOSAL NUMBER: 98-1 04.04-2321A

PROJECT TITLE: Design-Based Developments for Pump Cavitation Control

TECHNICAL ABSTRACT (LIMIT 200 WORDS)

This project offers a design-oriented developmental approach to improve fundamental knowledge and design techniques for high-performance, cavitating inducers. It is built upon an innovative approach to inducer design using bowed blading, sweep, and incidence, plus cover treatment concepts. On a step-by-step basis, this investigation deals with tradeoffs between blade shape, hence loading, and cavitation. It deals with blade design parameters such as solidity, leading edge shape (sweep), cant angle, tip speed, and clearance plus thickness effects. These parameters will be independently investigated in the laboratory with steady and dynamic measurements plus flow visualization. Computational fluid dynamics (CFD) is evaluated for modeling both non-cavitating and cavitating performance in an effort to more clearly understand this design problem. An advanced inducer is designed and tested in Phase I with low NPSH implying a suction specific speed of 65,000 to above 85,000 with an inducer flow coefficient of over 0.10. Tests will be conducted on CETI's magnetic bearing rig to collect force data. Measured results will be compared to the fundamental modeling. Overcoming current turbopump design thresholds due to cavitation, and related instabilities, is a critical path item for advanced propulsion technologies.

POTENTIAL COMMERCIAL APPLICATIONS

Improved design methods for cavitating inducers will be of immediate use to aerospace and industrial pumping companies. Information learned will be introduced into CETI's design software system used by industrial and rocket engine turbopump manufacturers. Our "Centrifugal Pump Design and Performance" course material will be updated based upon project results. The ability to optimize suction performance will allow increases in rotational speed. This will lead to smaller, less costly, more reliable turbopumps and industrial pumps.

NAME AND ADDRESS OF PRINCIPAL INVESTIGATOR

Dr. David Japikse
Concepts ETI, Inc.
4 Billings Farm Road
White River Junction , VT 05001

NAME AND ADDRESS OF OFFEROR

Concepts ETI, Inc.
4 Billings Farm Road
White River Junction , VT 05001