1、Best Practices Entry: Best Practice Info:a71 Committee Approval Date: 2000-04-17a71 Center Point of Contact: MSFCa71 Submitted by: Wil HarkinsSubject: Rocket Engine Technology Test Bed Practice Practice: Conduct highly instrumented tests of O2/H2rocket engine systems to: (1) evaluate and verify new
2、propulsion technologies; (2) validate or modify analytical models; (3) more fully understand the operation of rocket engine systems under varying performance conditions, and (4) ensure engine reliability and operability.Programs that Certify Usage: This practice has been used on Space Shuttle Main E
3、ngine (SSME), and Technology Test Bed (TTB) Program.Center to Contact for Information: MSFCImplementation Method: This Lesson Learned is based on Reliability Practice number PT-TE-1427 from NASA Technical Memorandum 4322A, NASA Reliability Preferred Practices for Design and Test.Benefit:Highly instr
4、umented engine system tests of varying configurations under varying conditions provides engine system level validation of advanced propulsion technology concepts prior to incorporation of these concepts into development or production units; provides an opportunity for greater understanding and fine-
5、tuning of analytical tools that characterize engine performance; results in the Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-development and improvement of diagnostic methods; and increases the depth of available knowledge about the inner workings
6、 sensitivities, and detailed performance characteristics of liquid rocket engine systems. The overall benefit are the validation of technology, improved system performance, high system reliability, and mission safety.Implementation Method:Experience in the planning and conduct of propulsion technol
7、ogy tests using the Space Shuttle Main Engine (SSME) has resulted in a systematic and methodical procedure for planning, testing, data analysis, and reporting the results of test bed activities. As seen in Table 1, the testing has ranged from evaluation of new engine components and features, to adva
8、nced diagnostic and sensor techniques, to the development of systems for anomaly and failure detection. A key to the continued success of this program has been a technology integration process that places emphasis on integration requirements and costs at an early point in the process. Figure 1 is a
9、flow diagram that depicts the technology integration process. Once an engine technology item has proceeded through the concept evaluation process to a point where a decision is made to pursue test bed evaluation, it is presented by the principal investigator to the Test Bed project manager for presc
10、reening review and then a technology item screening review.refer to D descriptionD Table 1. Typical Types of Technology Test Bed Testing Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-refer to D descriptionD Fig. 1. Technology Test Bed Technology In
11、tegration ProcessIn the screening review, an engine technology candidate is judged by its technical merit and potential benefit, the risk of testing the item on the Technology Test Bed engine, and the cost of integrating the item into the engine or facility. Key milestones in the process are Technol
12、ogy Item Screening, the Technology Item Final Design Review, the Integration Design Review, and Hot Fire Testing.Technology Item Final Design Review:Once the technology item is accepted as an output of Technology Item Screening, technology item development proceeds with the conduct of analytical stu
13、dies, component testing, and the incorporation of design revisions, if required. Then a Technology Item Final Design Review is conducted in which four subject areas are presented and discussed: (1) Technology Item Design Description; (2) Technology Item Design Verification; (3) System Issues; and (4
14、) Safety/Quality Issues. The Technology Item Design Description includes the design configuration and characteristics; the design intent or function; the design requirements; materials and processes, drawings and an integrated design configuration. The Technology Item Design Verification consists of
15、 the qualification approach, test and verification plans and results, supporting analysis and assurance that the design and performance meets the intent of the requirements. System Issues include system requirements, system compatibility issues, integration plans and issues, constraints, and Technol
16、ogy Test Bed test operational requirements. Safety/Quality Issues include quality assurance provisions such as fabrication processes and controls, traceability, vendor qualification, and nondestructive evaluation techniques; technology item life; risk assessment; hazards analysis; failure modes and
17、effects analysis; risk mitigation; materials certification; and supporting analyses. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-When the technology item final design review is successfully completed, fabrication can proceed and readiness certifi
18、ed upon acceptance.Technology Item Integration Design Review:The integration review is conducted to verify that the technology item can be accommodated safely and effectively into the TTB. It consists of: (1) an Integration Design Description; (2) Integrated Design Verification; (3) System Issues, a
19、nd (4) Safety/Quality Issues. The subject areas covered in the Technology Item Integration Design Review are similar to those for the Technology Item Final Design Review except that all factors are viewed from the standpoint of interaction of the technology item with the Test Bed and its related sub
20、systems, facilities, instrumentation, software and data.Hot Fire Testing and Results:A test plan is prepared for each test series, and it is reviewed at a pretest readiness review before each test. Instrumentation is configured in accordance with an Instrumentation Program and Command List (IP&CL).
21、A test results review is held after each test and a test report is prepared. When two or more tests are combined into a test series, a test series report is prepared. Examples of these documents are included in the list of References for this practice.Technical Rationale:In the conduct and analysis
22、of over fifty tests conducted in the Technology Test Bed program by MSFC since September 1988, the SSME TTB program has proven to be an indispensable tool in the validation of propulsion technology advances for large liquid oxygen/liquid hydrogen rocket engines. The program has also yielded numerous
23、 advances in measurement and diagnostic methods that are continuing to be used in the TTB program and are applicable to other similar test and evaluation scenarios. The TTBs highly instrumented engine employs over five times the number of measurements used for an acceptance test of a flight engine.
24、This in-depth instrumentation using flow meters, steady state pressure transducers, high frequency pressure measurements, thermocouples, strain gauges, accelerometers, and sophisticated laser and optics techniques has provided an unprecedented amount of detailed knowledge of the performance subtleti
25、es of large O2/H2engines under widely varying conditions. The program has yielded results that have permitted the incorporation of state-of-the-art technology advances without compromising engine reliability.References:1. “SSME Improved Characterization Using Highly Instrumented Engine Test Data,“ B
26、 Piekarski and J. Leahy, Martin Marietta, AIAA/SAE/ASME/ASEE 28th Joint Propulsion Conference, July 6-8, 1992, Nashville, TN, AIAA # 92-3451.2. “Space Shuttle Main Engine Technology Test Bed overview,“ H.V. McConnaughey, Provided by IHSNot for ResaleNo reproduction or networking permitted without l
27、icense from IHS-,-,-Advanced Earth-to-Orbit Propulsion Technology Conference, 1992, Huntsville, AL.3. “Technology Test Bed Program: Engine 3001 with Instrumented Turbopumps,“ NASA/MSFC Test Series Report No. TTB-DEV-EP93-001, January 15, 1993, Huntsville, AL.4. “Technology Test Bed Test Report: Engi
28、ne #3001,“ NASA/MSFC Report # EP52(92TR-033), August 1992, Huntsville, AL.5. “Technology Test Bed Program: Instrumentation Program and Command List,“ NASA/MSFC Document 1618, November 1989, Huntsville, AL.Impact of Non-Practice: Failure to conduct technology testing could result in the absence of re
29、liability enhancing improvements in the engine configuration and could cause subtle failure modes or performance limits to be unnoticed until critical points in the engine development or flight schedule.Related Practices: N/AAdditional Info: Approval Info: a71 Approval Date: 2000-04-17a71 Approval Name: Eric Raynora71 Approval Organization: QSa71 Approval Phone Number: 202-358-4738Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
