Author: National Aeronautics and Space Adm Nasa
Publisher:
ISBN: 9781730701535
Category :
Languages : en
Pages : 58
Book Description
The analytical results from two-dimensional (2D) and three-dimensional (3D) finite element model investigations into the cracking of Space Shuttle Main Engine (SSME) High Pressure Fuel Turbopump (HPFTP) first- and second-stage turbine blades are presented. Specifically, the initiation causes for transverse cracks on the pressure side of the firststage blade fir tree lobes and face/corner cracks on the downstream fir tree face of the second-state blade are evaluated. Because the blade material, MAR-M-246 Hf (DS), is highly susceptible to hydrogen embrittlement in the -100 F to 400 F thermal environment, a steady-state condition (full power level = 109 percent) rather than a start-up or shut-down transient was considered to be the most likely candidate for generating a high-strain state in the fir tree areas. Results of the analyses yielded strain levels on both first- and second-stage blade fir tree regions that are of a magnitude to cause hydrogen assisted low cycle fatigue cracking. Also evident from the analysis is that a positive margin against fir tree cracking exists for the planned design modifications, which include shot peening for both first- and second-stage blade fir tree areas. Lee, Henry Marshall Space Flight Center...
Space Shuttle Main Engine High Pressure Fuel Turbopump Turbine Blade Cracking
Author: National Aeronautics and Space Adm Nasa
Publisher:
ISBN: 9781730701535
Category :
Languages : en
Pages : 58
Book Description
The analytical results from two-dimensional (2D) and three-dimensional (3D) finite element model investigations into the cracking of Space Shuttle Main Engine (SSME) High Pressure Fuel Turbopump (HPFTP) first- and second-stage turbine blades are presented. Specifically, the initiation causes for transverse cracks on the pressure side of the firststage blade fir tree lobes and face/corner cracks on the downstream fir tree face of the second-state blade are evaluated. Because the blade material, MAR-M-246 Hf (DS), is highly susceptible to hydrogen embrittlement in the -100 F to 400 F thermal environment, a steady-state condition (full power level = 109 percent) rather than a start-up or shut-down transient was considered to be the most likely candidate for generating a high-strain state in the fir tree areas. Results of the analyses yielded strain levels on both first- and second-stage blade fir tree regions that are of a magnitude to cause hydrogen assisted low cycle fatigue cracking. Also evident from the analysis is that a positive margin against fir tree cracking exists for the planned design modifications, which include shot peening for both first- and second-stage blade fir tree areas. Lee, Henry Marshall Space Flight Center...
Publisher:
ISBN: 9781730701535
Category :
Languages : en
Pages : 58
Book Description
The analytical results from two-dimensional (2D) and three-dimensional (3D) finite element model investigations into the cracking of Space Shuttle Main Engine (SSME) High Pressure Fuel Turbopump (HPFTP) first- and second-stage turbine blades are presented. Specifically, the initiation causes for transverse cracks on the pressure side of the firststage blade fir tree lobes and face/corner cracks on the downstream fir tree face of the second-state blade are evaluated. Because the blade material, MAR-M-246 Hf (DS), is highly susceptible to hydrogen embrittlement in the -100 F to 400 F thermal environment, a steady-state condition (full power level = 109 percent) rather than a start-up or shut-down transient was considered to be the most likely candidate for generating a high-strain state in the fir tree areas. Results of the analyses yielded strain levels on both first- and second-stage blade fir tree regions that are of a magnitude to cause hydrogen assisted low cycle fatigue cracking. Also evident from the analysis is that a positive margin against fir tree cracking exists for the planned design modifications, which include shot peening for both first- and second-stage blade fir tree areas. Lee, Henry Marshall Space Flight Center...
Assessment of Crack Growth in a Space Shuttle Main Engine First-Stage, High-Pressure Fuel Turbopump Blade
Author: National Aeronautics and Space Adm Nasa
Publisher: Independently Published
ISBN: 9781729181836
Category : Science
Languages : en
Pages : 26
Book Description
A two-dimensional finite element fracture mechanics analysis of a space shuttle main engine (SSME) turbine blade firtree was performed using the MARC finite element code. The analysis was conducted under combined effects of thermal and mechanical loads at steady-state conditions. Data from a typical engine stand cycle of the SSME were used to run a heat transfer analysis and, subsequently, a thermal structural fracture mechanics analysis. Temperature and stress contours for the firtree under these operating conditions were generated. High stresses were found at the firtree lobes where crack initiation was triggered. A life assessment of the firtree was done by assuming an initial and a final crack size. Abdul-Aziz, Ali Unspecified Center NAS3-25266; RTOP 553-13-00...
Publisher: Independently Published
ISBN: 9781729181836
Category : Science
Languages : en
Pages : 26
Book Description
A two-dimensional finite element fracture mechanics analysis of a space shuttle main engine (SSME) turbine blade firtree was performed using the MARC finite element code. The analysis was conducted under combined effects of thermal and mechanical loads at steady-state conditions. Data from a typical engine stand cycle of the SSME were used to run a heat transfer analysis and, subsequently, a thermal structural fracture mechanics analysis. Temperature and stress contours for the firtree under these operating conditions were generated. High stresses were found at the firtree lobes where crack initiation was triggered. A life assessment of the firtree was done by assuming an initial and a final crack size. Abdul-Aziz, Ali Unspecified Center NAS3-25266; RTOP 553-13-00...
Assessment of Crack Growth in a Space Shuttle Main Engine First-stage, High-pressure Fuel Turbopump Blade
Space Shuttle Main Engine High Pressure Fuel Pump Aft Platform Seal Cavity Flow Analysis
Scientific and Technical Aerospace Reports
Space Shuttle Main Engine
Author: Robert E. Biggs
Publisher: American Astronautical Society
ISBN:
Category : Science
Languages : en
Pages : 284
Book Description
The first ten years : The engine -- The beginning -- The requirements -- The obstacles -- The goals -- The first flight -- The second decade : The glory of Columbia -- Full power level moratorium -- Full power level certification -- Program reassessment and realignment -- Phase I flight program -- The tragedy of Challenger -- Return to flight -- Building margin -- Beyond the second decade.
Publisher: American Astronautical Society
ISBN:
Category : Science
Languages : en
Pages : 284
Book Description
The first ten years : The engine -- The beginning -- The requirements -- The obstacles -- The goals -- The first flight -- The second decade : The glory of Columbia -- Full power level moratorium -- Full power level certification -- Program reassessment and realignment -- Phase I flight program -- The tragedy of Challenger -- Return to flight -- Building margin -- Beyond the second decade.
NASA Authorization for Fiscal Year 1980
Author: United States. Congress. Senate. Committee on Commerce, Science, and Transportation
Publisher:
ISBN:
Category :
Languages : en
Pages : 514
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 514
Book Description
Energy Research Abstracts
Scientific and Technical Aerospace Reports
Report to the President
Author: United States. Presidential Commission on the Space Shuttle Challenger Accident
Publisher:
ISBN:
Category : Space shuttles
Languages : en
Pages : 1316
Book Description
Publisher:
ISBN:
Category : Space shuttles
Languages : en
Pages : 1316
Book Description