NASA Goddard Space Flight Center s Cryogenics and Fluids Branch Code 552

Transcription

1 NASA Goddard Space Flight Center s Cryogenics and Fluids Branch Code 552 by Eric A. Silk, M.S., Ph.D. NASA Goddard Space Flight Center, Greenbelt, MD., Presented to Goddard Contractor s Association NASA Goddard Spaceflight Center Greenbelt, MD., September 8, 2016

2 Outline What is Cryogenics? History of the Branch Branch Personnel Lines of Business Technology Development Efforts Community Involvement/Outreach Conclusions 2

3 What is Cryogenics? 3

4 What is Cryogenics? Cryogenics is the art and/or science of making things cold. The NBS (National Bureau of Standards) defines cryogenic temperatures as beginning at 123K. Superconducting Magnets YBCO cubic magnet over BSSCO disc magnet in LN2 Key Notes: Fundamental physics based phenomena can change at low temperatures (i.e., cryogenic temperatures). Cryogenic payloads are becoming commonplace on NASA missions Cryogenics vs. Cryonics 4

5 Fundamental Cryogens 5

6 Cryogenic Materials Cryogenic engineering deals with the practical application of very lowtemperature process and techniques. The development of such processes and techniques often are in realm of low-temperature physics. Saturation Temperatures of Common Cryo-fluids at 1 atm 3 He 3.2 K CO 81.7 K 4 He 4.2 K Ar 87.3 K H K O K Ne 27.1 K CH K N K Kr K 6

7 Low Temperature Effects Fundamental physics based phenomena can change at low temperatures (i.e., cryogenic temperatures). YBCO cubic magnet over BSSCO disc magnet in LN2 Thermal Conductivity Specific Heat (single vs. multiple values) Structural Elasticity (Thermal expansions and/or contractions) Stiffness and/or Ductility (embrittlement may be prevalent) Electrical phenomena Superconductivity Quantum Effects Superfluid Helium (i.e., He-II) 7

8 Branch History 8

9 Brief Chronology : Cryogenics, Fluids, and Propulsion Branch was created as Code 713 Cryogenics sections developed cryogenic cooling systems Propulsion section developed spacecraft propulsion systems Fluids section supported cryogenic and propulsion fluid analyses and developed gas mixture systems 1997: Engineering Directorate had reorganization and became Code 500 Cryogenic and Fluids Branch (Code 552) was established within the Instrument Technology Center (now ISTD) Cryogenic and Fluids Branch focus on cryogenic cooling systems and gas mixture systems Propulsion, Code 574 later Code 597 was established within the Guidance, Navigation, and Control Center Most Fluids people transferred to Code 574 Remaining fluids work is in support of cryogenic fluids

10 Cryogenics & Fluids Facilities Building 7 Basement Laboratory Then Now 10

11 Cryogenics & Fluids Facilities Area 400 (Hazardous Test Facility) retained by Cryogenics and Fluids 11

12 What Does Code 552 Do? 12 Mission Proposals - Design of Temperature Control System Architectures - Technical expertise - Cryogenic Systems Engineering - Conceptual studies Technical Reviews - Spaceflight Programs (PDR, CDR, etc.) - SBIRs - BAAs - Strategic thrusts (e.g., NASA Roadmap) - Nationwide Space Grant Consortium submissions - IDL and MDL - Journals (e.g., Elsevier Journal of Applied Thermal Engineering) Technology Development - Design, analysis and test of cryogenic system components ADRs Cryocoolers Cryo-fluid storage/transfer systems Advanced Cryostats - Low Mid TRL promotion - Technology proposal development - Technology customization and infusion - External Code 552 technologies Optics Radiators Mechanisms Heat Pipes/LHPs Superconducting Detectors Engineering Support - Consulting - Product development and/or leadership - Structural and Thermal analysis - Design, development and assembly - Materials compatibility and testing - Training in proper handling of cryogens - Component fabrication - Purchasing and acquisitions (e.g., cryocoolers) - Technical oversight of contracts - On orbit analysis of cryosystems

13 Branch Personnel 13

14 Technical Backgrounds Degree Background Mechanical Engineering Aerospace Engineering Materials Science & Engineering Low Temperature Physics Nuclear Physics Degree Levels Ph.D. (11) Masters (6) Bachelors (7) Statistics 30 Branch Members 26 Civil Servants 4 Contractors 27 Full Time Employees 3 Co-ops 14

15 Lines of Business 15

16 Key Lines of Business Cryogenic Temperature Control System Magnetic Refrigeration Systems Mechanical Cryocoolers Cryogenic & Microgravity Fluid Management Thermophysical Properties Testing 16 Cooling system design, fabrication, assembly and test ADR & HTS Leads SME Contract technical support Cryocooler integration and testing Cryocooler SME Contract technical support Dewar and fluid system design, assembly and testing Cryofluid SME Contract technical support Technical Support SME for low temperature thermal performance of materials Cryogenic testing

17 Sub-Kelvin Cooling Dilution Refrigeration using He 3 /He 4 mixture (mk scale) Nuclear Demagnetization Refrigeration (µk scale) Adiabatic Demagnetization Refrigeration (mk scale) Notes: Dilution refrigeration has been performed on spaceflight missions in an open loop cycle. Adiabatic Demagnetization Refrigeration has been successfully demonstrated in space on Astro-E2 and Astro-H. 17

18 Entropy [J/mol-K] ADR Systems Adiabatic Demagnetization Refrigeration relies upon magnetic cooling of a paramagnetic material. Heat transfer is fostered through the magneto-caloric affect. S 1 S 3 =S H 0 =0 δq= T 1 (S 1 -S 2 ) H=H 1 Step 1-2: Pre-cool via coupling to cold sink and apply a magnetic field Step 2-3: Isolate paramagnet from cold sink, reduce magnetic field to initial value Step 3-1: System reconditions to initial value 18 T 2 T 1 Temperature [mk]

19 ADR System Component 5 key components for each stage Paramagnetic material Superconducting magnet Heat switch Thermally isolating support structure Thermometers Lateral suspension Ti ; Shell mm thick Paramagnetic Materials Superconducting Magnet 19

20 HTS Leads High Temperature Superconducting leads are used to provide current to the ADR system internal to the cryogenic volume without producing residual heating. Note: In the superconducting state, electrical resistance approximates to 0 Ohms. 20

21 Goddard Flight Systems Astor-E XRS Astor-E2 XRS2 Astro-H SXS Astro-E XRS Launch Date: 2000 Est. Lifetime: 2 years Ne/He/ADR System Astro-E2 XRS2 Launch Date: 2005 Est. Lifetime: 3 years Ne/He/ADR System Astro-H SXS Launch Date: 2016 Est. Lifetime: 3 years He/ADR System 21

22 Cryogenic & µ-g Fluid Mgmt. Traditionally, Cryogenic materials (in either solid or liquid phase) have been used to foster cooling to desired cryogenic temperatures. Solid Cryogens Argon (Triple Point Temperature = 83.8 K) Nitrogen (Triple Point Temperature = 63.2 K) Neon (Triple Point Temperature = 24.4 K) Hydrogen (Triple Point Temperature = 14.0 K) Liquid Cryogens 4 He (Lambda Point Temperature = 2.17 K) 3 He (0.34 K) Note: Cryomaterials provide cooling over temperature range Kelvin with some gaps. 22

23 Stored Cryogens Capable of operating with 300 K main shell Bulk cooling available Lifetime limited by heat input and mass/volume constraints Dt = ml/q where Dt = lifetime, m = mass, l = heat of vaporization or sublimation, and Q is the total heat input Substantial ground and launch pad operations System is active any time it contains cryogens Cryogen must be conditioned prior to launch to maximize on-orbit lifetime Hazards associated with stored cryogens Extreme cold Asphyxiation Overpressurization 23

24 Stored Cryogen Missions Mission Launch Cooler Issues Mission Outcome NIMBUS 6/LRIR 1975 Solid NH 3 /CH 4 Premature boiloff Successful HEAO-B 1978 Solid NH 3 /CH 4 Premature boiloff Successful NIMBUS 7/LRIR 1978 Solid NH 3 /CH 4 Premature boiloff Successful COBE 1989 SHe None Outrageous success! SHOOT 1993 SHe, K Ice plugs in emergency vent line Successful NICMOS 1997 Solid Nitrogen Distortion of dewar from expansion of SN2 Focus issues; short lifetime; retrofitted w/ cryocooler WIRE 1999 Solid Hydrogen Premature ejection of cover Loss of mission XRS1/Astro-E SHe/Solid Neon None Rocket failure Spitzer (SIRTF) 2003 SHe Ice plug in vent line Recovered XRS2/Astro-E SHe/Solid Ne/cryocooler Ice plug and explosion of GSE helium tank; contamination of dewar guard vacuum with He gas on orbit Successful operation (2 weeks) until catastrophic venting of He WISE 2009 Solid H 2 /H 2 Premature boiloff Successful Astro-H/SXS 2016 Cryocooler/He- II/ADR Loss of spacecraft on orbit Set new low temperature record. Incomplete science survery. 24

25 Stored Cryogens SHOOT: 1993 launch Demonstrated cryogen transfer between tanks 25 COBE: 1989 launch Achieved 10 month lifetime Helium Heat Load 70 mw XRS: 2000 launch XRS2: 2005 launch Neon Heat Load 100 mw Helium Heat Load 1 mw

26 Robotic Refueling Mission 3 Transfer of liquid phase cryogen from a source dewar to a receiver dewar No vent transfer No mechanical pumping of cryogen 552 is Lead for Cryogen Demonstration System ISS is µ-g platform Ground System Cryogen Freeze Testing Using Argon 26

27 Mechanical Coolers Cryocoolers are mechanical coolers designed for cooling to cryogenic temperatures. Cooling available over temperature range K Cryocooler designs are optimized to operate at a particular temperature, and effectively cover a small range of temperatures Most cryocoolers in-orbit are single-stage coolers operating at T > 55 K Temperature lift for heat rejection Compressor operates at ~ K Planetary missions need K compressor 27

28 Types of Cryocoolers System Type AC DC Compressor Heat Exchanger Cold End Type Component Cooler Name Mechanical Regenerator Displacer Stirling Mechanical Regenerator Pulse Tube Pulse Tube Mechanical Recuperator Turbine Turbo-Brayton Mechanical Recuperator J-T Valve J-T Cooler Example Joule-Thompson Cycle W ṁ Recuperative Heat Exchanger Heat Exchanger J-T Expansion Valve Q in 28 Note: Cryocoolers typically perform somewhere between 3% and 8% of their Carnot efficiency.

29 Types of Cryocoolers 29 Reverse Turbo-Brayton High speed rotary compressor and expander Recuperative heat exchanger Moving parts supported by gas bearings Stirling Linear compressor with pneumatically driven displacer Regenerative heat exchanger Moving parts supported by flexure springs or gas bearings Most cryocoolers on-orbit are Stirling cycle machines Pulse tube Linear compressor with tuned expansion pipe Regenerative heat exchanger No cold moving parts Joule-Thompson Isenthalpic expansion of gas through an orifice Sometimes used as low temperature stage for a Stirling or pulse tube cooler

30 Cryocooler Missions Left: Sunpower M77 (RHESSI) Above: Creare Reverse Brayton (HST/NICMOS) Above: NGST Pulse Tube (MIRI JT Pre-cooler) 30 Right: Ball Stirling (LDCM/TIRS)

31 Operational Features 31 Point cooling Cooling at multiple locations requires thermal distribution system (e.g., copper or aluminum straps, capillary pumped loop) Multi-stage coolers can provide point cooling at different temperatures Anticipated lifetime is 5-10 years Electronics may be life-limiting component for many cryocoolers Low-cost cryocoolers are expected to have lower reliability Vibration Linear cryocoolers (Stirlings and pulse tube coolers) have residual vibrations on the order of 1 N Can be reduced by an order of magnitude in the axial direction using vibration cancellation algorithm in the drive electronics Rotary cryocoolers (Reverse Turbo-Brayton) have no measurable vibration

32 Thermophysical Properties Lab New laboratory brought online in summer 2016 Two cryostats capable of temperature testing 4K 300K Thermal Conductivity and Emissivity measurements 32

33 Summary of Missions Mission Past Present Future Magnetic Refrigeration Systems Astro-E Astro-E2 Astro-H PIPER HIRMES Astro-H2? PIXIE SGG Far IR Telescope Cryocoolers RHESSI HST/NICMOS EOS- AURA/HIRDLES, GOES-RBI TIRS-I TIRS-II WFIRST WFIRST PIXIE SGG Far IR Telescope Cryogenic & Microgravity Fluid Management NIMBUS 6, HEAO-B NIMBUS 7, COBE, SHOOT, NICMOS, WIRE, Astro-E, Spitzer, Astro-E2, WISE, Astro-H RRM3 TiME Thermophysical Properties Measurements Astro-H OVIRS Hybrid Plane JWST WFIRST Airborne missions 33

34 Technology Development Efforts 34

35 SBIRs Agency Subtopics Supported S1.09: Cryogenic Systems for Sensors and Detectors (Lead) H2.01: Cryogenic Fluid Management Technologies (Participant) S3.07: Thermal Control Systems (Participant) Present Awards Phase II: A High Efficiency 30-K Cryocooler with Low Temperature Heat Sink, Creare Phase I: A Shielded 3-T HTS ADR Magnet Operating at 30-40K, Superconducting Systems, Inc. 35

36 A Low-G Ideal Integrating Bolometer (IIB) PI: Ed Canavan/552 Description and Objectives: (Why) : We propose to develop a novel detector to enable a new class of far-ir spectroscopic surveys. Achievable sensitivity for these devices is roughly 2 orders of magnitude better than current devices. By reducing detection times by a factor of , the IIB enables rapid surveys of cosmological volumes. Key challenge(s)/innovation: Circumvent limitations on bolometer sensitivity through the use of: a phononic crystal, an array of holes optimized to minimize phonon transmission, to obtain extremely low conductance a micro-scale superconducting heat switch to control heat flow Approach: (How) In FY15 effort, fabricated micro-heat switch, and successfully demonstrated switching of electrical conductance; thermal conductance testing underway. Proposed effort will integrate the heat switch onto a phononic crystal structure, currently in development under a separate effort Application / Mission: (Future Plans) A background-limited high resolution far-infrared (0.3 3 THz) spectrometer, initially for balloon observatories, eventually for the Far-IR Surveyor mission. Collaborators: A. Kogut/665, T. Stevenson/553, K. Denis/553 Canavan (GSFC/ 552) 09/11/2015 Completed test chip Superconducting heat switch Micrograph of IIB pixel FTE and Procurement Allocation: 0.85 FTE / $30k procurement / $10k WYE Top Level Milestones and Schedule: Q1: Complete testing of micro heat switch; complete design of new devices Q2 Q3: fabricate devices Q4: complete device testing Space Technology Roadmap Mapping: 8.1.1: Detectors and focal planes Technology Readiness Level: Starting TRL: 2; End TRL 3 Isolated membrane

37 Introduction Cryogenic LH2+LO2 Propulsion for Planetary Science Mission NASA/ GSFC, NASA/ MSFC PI: Shuvo Mustafi Cryogenic Liquid Hydrogen (LH2) and Liquid Oxygen (LO2) propellants provides the highest specific impulse for any practical chemical propulsion system LH2+LO2 propulsion provides high V and/or high dry mass spacecraft with lower spacecraft wet mass. A detailed design study comparing LH2+LO2 propulsion with conventional hypergolic propulsion using Mono Methyl Hydrazine (MMH) and Nitrogen Tetra Oxide (NTO) was performed by GSFC and MSFC on a representative mission to Titan, the Titan Orbiter Polar Surveyor (TOPS) Years Cryogenic Propellant Storage Mission Launch in 2022 Jupiter is not available for a gravity assist. V = 5887m/s; Non-Main Propulsion Dry Mass = kg; Science Payload Mass = 53.3 kg; 7 Engine Burns Contact: Shuvo Mustafi shuvo.mustafi@nasa.gov, TOPS Design Study Results For the TOPS mission, passively cooled LH2+LO2 reduces launched spacecraft mass by 43% and allows for launch on an Atlas launch vehicle. The same mission cannot be performed using a MMH+NTO propulsion and an Atlas launch vehicle. Subcooling cryogenic propellants on the launch pad enables multiyear storage of LH2 without adding launched mass. For the TOPS Mission Subcooling saved LH2 boil-off mass that amounts to 56% of science payload mass. Subcooling triples the in-space vent-free hold time of LH2 by just processing the hydrogen on the ground. LH2+LO2 propulsion provides an enabling solution for many missions that have high V and/or high dry mass constraints, such as missions to and from many planetary science destinations including planets, moons, asteroids, comets. TOPS Mission and other planetary science missions can be accomplished without any in-space active cooling. LH2+LO2 Propulsion Required Technology Storage High Performance Advance Multi-Layer Insulation Low Conductivity Supports Launchpad subcooling to enhance long duration in-space storage Propellant Tank Pressure Control Tank Liquid Acquisition Devices 890 N (200 lbf) LH2+LO2 Engine Electric Pumps and Motors Igniters Injector and Chamber Design Long-life Cryogenic Valves Application / Mission: Science Missions to Outer Planets/Moons/ Asteroids In-Space Cryogenic Upper Stages and Depots Flexible architecture Human Missions Asteroid Missions, Martian Missions, Lunar Mission High Isp Advanced Electric Propulsion Missions Cryogenic Hydrogen Radiation Shielding

38 Community Involvement/Outreach 38

39 Outreach Activities USA Science and Engineering Festival (2014) NASA Goddard Science Jamboree (annually) DC Elementary Student Science Project Consulting (2016) SCW: Space Cryogenics Workshop (every 2 years) CEC: Cryogenics Engineering Conference (every 2 years) AIAA Aerospace Sciences Meeting (annually) AIAA Summer Thermophysics Conference (annually) Tour of Cryogenics and Thermal laboratory facilities to ASME HTFEICNMM conference (2016) CEC Organizing Committee (Dr. Michael J. Dipirro) American Editor for Elsevier s Journal of Cryogenics (Dr. Peter Shirron). AIAA Thermophysics Technical Committee Past Chair (Dr. Eric A. Silk) 39

40 Outreach Activity Photos 2014 USA Science & Engineering Festival Goddard Science Jamboree LN2 Ice Cream: Before LN2 Ice Cream: After 40

41 Conclusions Code 552 provides world class expertise in the design and development of low temperature cooling systems for spaceflight applications. We welcome partnerships across NASA, the government, the education community and private industry. 41

42 Thank You Branch Head: Eric A. Silk Assoc. Branch Head: Hudson Delee Branch Secretary: Saiqa Huda

43 Questions 44

44 Extras

45 Titanium Shell Body Heat Switch Larger body allows larger surface area for higher on-conductance Shell body Ti ; ~0.127 mm (0.005 inch) thick