THE CONTRACTOR SHALL DEVELOP AN INJECTION HOLD GEOMETRY THAT IS COMPATIBLE WITHIN THE PHYSICAL CONSTRAINTS…

Public award description

THE CONTRACTOR SHALL DEVELOP AN INJECTION HOLD GEOMETRY THAT IS COMPATIBLE WITHIN THE PHYSICAL CONSTRAINTS OF THE EXISTING 61 ELEMENT THRUSTER HARDWARE. THE CONTRACTOR SHALL PERFORM ALL STRUCTURAL AND FLOW ANALYSIS NEEDED TO VALIDATE THE FUNCTION AND PERFORMANCE OF THE REPLACEMENT FACEPLATE DESIGN. THE CONTRACTOR SHALL FABRICATE, TEST AND DELIVER THREE INJECTOR FACEPLATES WITHIN THE TIME CONSTRAINTS OF THE CONTRACT. THE REPLACEMENT INJECTOR FACEPLATES MUST BE COMPATIBLE WITH EXISTING NASA HARDWARE. THE CONTRACTOR IS RESPONSIBLE FOR ALL DESIGN, FABRICATION, TESTING AND DELIVERY OF THE REPLACEMENT INJECTOR FACEPLATES. NASA WILL PROVIDE ALL TECHNICAL INFORMATION ABOUT EXISTING HARDWARE AND PROPELLANT FLOW CONDITIONS THAT ARE ANTICIPATED FOR OPERATIONAL USE. AN EXISTING INJECTOR ASSEMBLY AND THRUSTER CHAMBER WILL BE USED WITH THE REPLACEMENT INJECTOR FACEPLATES. IN ORDER TO DROP INTO THIS EXISTING LABORATORY HARDWARE, THE REPLACEMENT INJECTOR FACEPLATES SHALL HAVE EXTERIOR MECHANICAL INTERFACES IDENTICAL TO THAT SHOWN IN NASA DRAWING 623862. AN EXISTING 69-ELEMENT OXYGEN INJECTOR WILL BE USED WITH THE REPLACEMENT INJECTOR FACEPLATES. THE INTERIOR MECHANICAL INTERFACES OF THE OXYGEN INJECTOR ARE SHOWN IN NASA DRAWING 623862. THE REPLACEMENT INJECTOR FACEPLATES SHALL ALSO BE COMPATIBLE WITH THE 1/8 INCH PRESSURE TAP TUBE, AND INCLUDE TWO HOLE OPENINGS AT DIAGONALLY OPPOSITE CORNERS. THE REPLACEMENT INJECTOR FACEPLATES WILL BE USED OVER A RANGE OF CHAMBER PRESSURES AND MIXTURE RATIOS UNDER LABORATORY CONDITIONS. THE FUEL INJECTOR HOLES WITHIN THE FACEPLATES SHALL HAVE FLOW CHARACTERISTICS COMPATIBLE WITH INFORMATION SHOW IN FIGURE 1 AND TABLE 1. TYPICALLY, THE FACEPLATES ARE TO OPERATE WITH GASEOUS OXYGEN OXIDIZER AND GASEOUS METHANE FUEL OVER A PC RANGE OF FROM 1.3 TO 4.0 FOR DURATIONS OF APPROXIMATELY 5 SECONDS. IT IS UNDERSTOOD THAT ACTUAL OPERATION AT STOICHIOMETRIC MR IS NOT TO BE USED AS A DESIGN LIMITING PARAMETER. THE DESIGN IS TO UTILIZE THE EXISTING GOX/H2 OPERATIONAL CHARACTERISTICS AS GUIDELINES FOR THERMAL DISTRIBUTION AND MAXIMUM PRESSURE DROP. THERE IS ALSO A DESIRE TO REDUCE OVERALL FACEPLATE FUEL PRESSURE DROP AND IN NO CASE EXCEED THE CURRENT DROP. VERIFICATION OF UNIT PRESSURE DROP SHALL BE BY COLD FLOW. WHILE THE THERMAL DISTRIBUTION OF THE EXISTING INJECTOR FACEPLATES, WHEN TESTED WITH GOX/H2 IS KNOWN TO BE LESS THAN UNIFORM, THE GOAL IS TO PROVIDE NO WORSE DISTRIBUTION. LIMITED ANALYSIS SHALL BE PERFORMED TO ASSESS THIS GOAL; NO FUNCTIONAL VERIFICATION NEED BE PERFORMED.