NASA Selects 5 Space Transportation Projects for SBIR Phase II Funding

NASA has selected five propulsion projects for phase 2 funding under its Small Business Innovation Business (SBIR) program. The space agency will enter into negotiations with the five companies on contracts worth up to $750,000 over two years.

Three of the projects involve technology for the storage and transfer of cryogenic propellants in space. The other two projects would fund development of nuclear systems.

The selected projects include:

• Lightweight, High-Flow, Low Connection-Force, In-Space Cryogenic Propellant Coupling — Altius Space Machines, Inc, Broomfield, CO
• Innovative Stirling-Cycle Cryocooler for Long Term In-Space Storage of Cryogenic Liquid Propellants — Converter Source, LLC, Athens, OH
• Proposal Title: A High Efficiency Cryocooler for In-Space Cryogenic Propellant Storage — Creare, LLC, Hanover, NH
• Joining of Tungsten Cermet Nuclear Fuel — Plasma Processes, LLC, Huntsville, AL
• Accident Tolerant Reactor Shutdown for NTP Systems — Ultra Safe Nuclear Corporation, Los Alamos, NM

Summaries of the proposal follow.

Proposal Title:
Lightweight, High-Flow, Low Connection-Force, In-Space Cryogenic Propellant Coupling
Subtitle Topic:
Cryogenic Fluid Management for In-Space Transportation

Small Business Concern
Altius Space Machines, Inc.
Broomfield, CO

Principal Investigator/Project Manager
Jonathan Andrew Goff

Estimated Technology Readiness Level (TRL) at beginning and end of contract:
Begin: 3
End: 6

Technical Abstract

Three of the key abilities needed for making future NASA and commercial launch and in-space transportation systems more affordable and capable are:

a) the ability to “live off of the land” via in-situ resource utilization (ISRU),
b) the ability to reuse in-space transportation hardware, and
c) the ability to leverage continuing advancements in lower-cost earth-to-orbit transportation.

All of these abilities require the ability to transfer large quantities of cryogenic liquids (Oxygen, Hydrogen, and Methane) between tanks on separate vehicles. While all cryogenic rocket stages have to have a propellant fill/drain coupling for loading propellant on the ground, existing designs are not capable of in-space refuelability. A dual-purpose coupler that could be used for both ground fill/drain and for in-space refueling would be extremely valuable.

In this proposed SBIR Phase II research effort, Altius Space Machines proposes continuing the development of just such a dual-purpose, lightweight, high-flow cryogenic propellant coupling to enable both ground fill/drain and in-space refueling. This coupling incorporates an innovative new cryogenic sealing architecture to enable a coupling with very low insertion/extraction forces, for manual, robotic, and astronaut-connected cryogenic propellant transfer operations.

In Phase I, Altius demonstrated the innovative new cryogenic sealing architecture, and performed insertion/extraction and leak tests, demonstrating significant improvements over traditional spring-energized polymer seals, raising the TRL from 2 to 3 at the end of Phase I.

In Phase II Altius will continue refinement of the cryogenic sealing architecture, and will design, fabricate, and test a family of couplers based on this architecture, and focused on an industry-provided launch vehicle application. Testing of the ground and in-space couplers during Phase II will raise the system TRL to 6, paving the way for Post-Phase II flight demonstration (yielding TRL 9).

Potential NASA Commercial Applications

Potential NASA applications include:

1- An integrated T-0 fill coupling for EUS that enables in-space refueling with the same coupling. This would enable refueling of the EUS upper stage in LEO or other in-space locations, enabling stage reuse, and/or launch of much larger payloads to deep space trajectories.

2- Fueling of Martian or Lunar Ascent Vehicles or future fully-reusable Mars or Lunar landing vehicles from ISRU production facilities.

3- Distributed launch for very high-energy robotic science missions.

Potential Non-NASA Commercial Applications

Potential Non-NASA applications include:

1- A combined T-0 coupling/in-space cryogenic transfer coupling that can be integrated into future upper stage designs, such as the planned ULA ACES or New Glenn cryogenic upper stages.

2- In-flight topoff couplings for air-launched liquid-propellant launch vehicles.

3- Refueling of commercial cryogenic stages in space for distributed lift missions, enabling direct insertion to GEO, or high energy earth departures for science missions.

4- Other terrestrial applications that could benefit from a low-connection force cryogenic coupling, such as automated LH2 fueling for fuel-cell cars.

5- The innovative cryogenic sealing architecture also has elements that could potentially be extrapolated to low insertion force, resettably-self-fusing high-power electrical connectors.

Technology Taxonomy Mapping

• Cryogenic/Fluid Systems
• Fasteners/Decouplers
• Fuels/Propellants
• Pressure & Vacuum Systems
• Robotics (see also Control & Monitoring; Sensors)
• Tools/EVA Tools

Proposal Title: Innovative Stirling-Cycle Cryocooler for Long Term In-Space Storage of Cryogenic Liquid Propellants
Subtopic Title: Cryogenic Fluid Management for In-Space Transportation

Small Business Concern
Converter Source, LLC
Athens, OH

Principal Investigator/Project Manager
Laurence Penswick

Estimated Technology Readiness Level (TRL) at beginning and end of contract:
Begin: 2
End: 3

Technical Abstract

Under this Phase II SBIR project we will build and test a stirling-cycle cryocooler and coolant circulating subsystem for use with broad area cooling (BAC) systems to deliver reduced or zero boil-off propellant storage. We will also refine the design of an innovative linear-reciprocating cold-circulator that resides at the same temperature as the BAC coolant, although we will not have the resources to build this component in Phase II. Compared to conventional reverse turbo-brayton cycle cooling technology our stirling-cycle technology offers higher cooling efficiency and requires no bulky recuperator component. Our double-acting stirling cycle configuration combines a linear motor with a moving piston/regenerator assembly into a self-contained module. A number of such modules can be connected together into several possible cryocooler layouts to scale heat lift capacity, achieve system redundancy and provide flexible integration with the BAC coolant loop. This modular approach provides the system designer with packaging options not available with conventional stirling cryocoolers.

Potential NASA Commercial Applications

Space-based Cryocooling – The cryocooler we will build can be used to produce cooling in the temperature range of 75 – 120 K. Lower operating temperatures are possible via staging. Potential applications include direct cooling of space sensors, vapor re-liquefaction for zero boil-off fluid storage or cooling superconducting magnetic bearings in support of flywheel energy storage systems.

Space-based Refrigeration and Compression – The core cryocooler and linear motor technology could be applied to build higher-temperature Stirling coolers for in-space scientific experimentation or biological material preservation. The same enabling technology could be used to build linear compressors for refrigerant-based cooling or other working gas compression or fluid pumping.

Potential Non-NASA Commercial Applications

Cryocooling – The cryocooler could be used to cool high-temperature superconducting magnetic bearings in industrial spindles and motors. The ability to cool a central load and reject heat at the periphery is ideal for zero boil-off re-condensation of liquid nitrogen, volatile fuels and other substances.

Refrigeration and Gas Compression – The core hydrodynamic bearing technology could be applied to linear free-piston compressors for domestic refrigeration. The Department of Energy Office recently issued a new report which prioritized accelerating the commercialization of high-efficiency appliance technologies. This Roadmap ranked the development of advanced compressor technologies for refrigerators and freezers as having the highest overall importance and potential impact.

Technology Taxonomy Mapping

• Active Systems
• Cryogenic/Fluid Systems
• Fuels/Propellants
• Heat Exchange
• Isolation/Protection/Shielding (Acoustic, Ballistic, Dust, Radiation, Thermal)
• Machines/Mechanical Subsystems
• Models & Simulations (see also Testing & Evaluation)
• Simulation & Modeling

Proposal Title: A High Efficiency Cryocooler for In-Space Cryogenic Propellant Storage
Subtopic Title: Cryogenic Fluid Management for In-Space Transportation

Small Business Concern
Creare, LLC
Hanover, NH

Principal Investigator/Project Manager
Mark V Zagarola

Estimated Technology Readiness Level (TRL) at beginning and end of contract:
Begin: 3
End: 4

Technical Abstract

NASA is considering multiple missions involving long-term cryogen storage in space. Liquid hydrogen and liquid oxygen are the typical cryogens as they provide the highest specific impulse of practical chemical propellants. These cryogens are stored at temperatures of nominally 20 K for hydrogen and 90 K for oxygen. Due to the large size of these tanks, refrigeration loads to maintain zero-boil-off are high, on the order of tens of watts at 20 K and hundreds of watts at 90 K. Space cryocoolers have been developed for cooling space sensors that have modest cooling loads and are not suitable for high capacity applications. On this program, we proposed to develop a high capacity turbo-Brayton cryocooler that provides 150 W of refrigeration at 90 K. On the Phase I project, we developed a preliminary design of the 90 K cryocooler, assessing its size, mass, performance, and maturity. The proposed cryocooler significantly exceeds the performance targets set forth in the solicitation — the cryocooler specific power is only 8 W/W (solicitation goal of 15 W/W), and the specific mass is 0.4 kg/W (solicitation goal of 12 kg/W). On the Phase II project, we propose to develop and demonstrate the least mature components, the compressor and its inverter drive. On a future Phase III project, we plan to build and demonstrate an engineering model cryocooler. Successful completion of this project fills a clear void in space cryocooler technology.

Potential NASA Commercial Applications

Space applications for high-capacity turbo-Brayton cryocoolers include cryogen storage for planetary and extraterrestrial exploration missions, CEVs, extended-life orbital transfer vehicles, long-term geosynchronous missions, in-space propellant depots and extraterrestrial bases, and cooling systems for observation platforms requiring large arrays of infrared and X-ray detectors. Terrestrial applications include cooling for spaceport cryogen storage and transportation systems. The highly reliable and space-proven turbo-Brayton cryocooler is ideal for these missions.

Potential Non-NASA Commercial Applications

Private sector applications for high-capacity turbo-Brayton cryocoolers include cooling for laboratory- and industrial-scale gas separation, liquefaction, cryogen storage and cryogen transportation systems; high-temperature superconducting magnets in motors, generators, transmission lines, and magnetic resonance imaging systems; liquid hydrogen fuel cell storage for the automotive industry; and commercial orbital transfer vehicles and satellites.

Technology Taxonomy Mappping

• Cryogenic/Fluid Systems

Proposal Title: Joining of Tungsten Cermet Nuclear Fuel
Subtopic Title: Nuclear Thermal Propulsion (NTP)

Small Business Concern
Plasma Processes, LLC
Huntsville, AL

Principal Investigator/Project Manager
John Scott O’Dell

Estimated Technology Readiness Level (TRL) at beginning and end of contract:
Begin: 2
End: 4

Technical Abstract

Nuclear Thermal Propulsion (NTP) has been identified as a critical technology needed for human missions to Mars and beyond due to its increased specific impulse (Isp) as compared to traditional chemical propulsion systems. Recently, the Game Changing Development (GCD) Program, which is a partnership between NASA, DOE, and industry, was initiated to evaluate the feasibility of a low enriched uranium (LEU) NTP system. A critical aspect of NTP is to develop a robust, stable fuel. One of the fuel configurations currently being evaluated is a W-UO2 cermet. Fabrication of full-size cermet elements (>20?) has proven to be difficult. As a result, the use of cermet segments to produce a full-size fuel element is of interest. However, techniques for joining the segments are needed. During Phase I, diffusion bonding techniques were developed for producing fuel elements from cermet segments. Microscopic examination and preliminary properties testing showed excellent joints were formed. For example, quantitative tensile testing of W samples produced at 1500C HIP with a Nb interfacial coating showed the failures were in the bulk W and not at the Nb-W interfaces. Therefore, the strength of the joints were greater than the strength of the bulk W material. Using the most promising fabrication methods, a 6.3′ long simulated cermet fuel element comprised of twenty-five 0.25′ thick segments was produced to demonstrate proof-of-concept. During the Phase II investigation, the HIP diffusion bonding process will be optimized for making W cermet based fuel elements. This will be accomplished by performing a process parameter-characterization-properties study. The optimized fabrication methods will then be used to make prototype fuel elements with W claddings and subscale fuel elements for delivery to NASA for hot hydrogen testing.

Potential NASA Commercial Applications

NASA applications that would benefit from this technology include Nuclear Thermal Propulsion (NTP) and Nuclear Electric Propulsion (NEP). For example, the proposed Phase II effort directly supports the goals of NASA’s GCD Program. Initial NTP systems will have specific impulses roughly twice that of the best chemical systems, i.e., reduced propellant requirements and/or reduced trip time. During Phase II-X and III, full-size full elements will be fabricated for testing in NTREES. Potential NASA missions include rapid robotic exploration missions throughout the solar system and piloted missions to Mars and beyond, where power from solar panels becomes more difficult to obtain.

Potential Non-NASA Commercial Applications

Both government and commercial entities in the following sectors would benefit from the development refractory metal coatings and diffusion bonding: defense, material R&D, nuclear power, aerospace, propulsion, automotive, electronics, crystal growth, and medical. Targeted commercial applications include high temperature-corrosion resistant claddings for nuclear fuel rods, hot gas path rocket motors, net-shape fabrication of refractory rocket nozzles, crucibles, heat pipes, and propulsion subcomponents; and advanced coating systems for x-ray targets, sputtering targets, turbines, and rocket engines.

Technology Taxonomy Mapping

• Ceramics
• Coatings/Surface Treatments
• Composites
• Fuels/Propellants
• Joining (Adhesion, Welding)
• Metallics
• Processing Methods
• Prototyping
• Spacecraft Main Engine

Proposal Title: Accident Tolerant Reactor Shutdown for NTP Systems
Subtopic Title: Nuclear Thermal Propulsion (NTP)

Small Business Concern
Ultra Safe Nuclear Corporation
Los Alamos, NM

Principal Investigator/Project Manager
Paolo Venneri

Estimated Technology Readiness Level (TRL) at beginning and end of contract:
Begin: 3
End: 4

Technical Abstract

In brief, USNC’s accident submersion safe drums are control drums where a small amount of fuel is added opposite to the neutron absorber and the drums impinge on the active core to substantially increase the shutdown criticality margin of the control drums. Phase 1 results indicate that the shutdown criticality margin is more than sufficient to maintain sub-criticality in the worst-case water submersion accidents. Key accidents that the accident submersion safe drums address include submersion in freshwater and sand with a stuck drum in the full-on position and submersion in water and wet sand with reflector loss.

This SBIR will develop the submersion safe reactor shutdown system for Nuclear Thermal Propulsion (NTP) identified in the Phase 1. Remaining subcritical during a during water submersion accident is a design requirement for NTP systems. As of now, all thermal spectrum NTP concepts (including LEU NTP systems) fail to remain subcritical during water submersion and thus are not water submersion safe. USNC’s submersion safe control drums enable thermal spectrum NTP systems to remain subcritical during water submersion accidents.

Key tasks that will be completed include:

1. Develop a detailed integrated thermal-mechanical and neutronic design of the control drums.

2. Design a power cycle and coolant paths that adequately remove heat from the submersion safe drums while minimizing complexity of the NTP system.

3. Demonstrate the Submersion safe control drum technology in a prototypical reactor experiment and raise the technology’s TRL up to 4/5.

4. Deliver a set of NTP system point designs that showcase the full implementation of the drums integrated into a realistic NTP system.

Potential NASA Commercial Applications

NTP has great promise in spreading human presence to Mars and other locations beyond low earth orbit. USNC’s submersion safe control systems will address key needs in NTP development to make NTP a viable technology to fulfill NASA human exploration needs. USNC’s work directly aligns with the NASA Technological Roadmap 2015 “TA 2: In-Space Propulsion Technologies: 2.2.3 Thermal Propulsion” .

Currently, NTP and USNC’s submersion safe reactor shutdown technology are being investigated for a human Mars Mission in the 2030s time frame, but NTP also has application for many other applications beyond low earth such as lunar exploration architectures and robotic missions into deep space.

In the near term USNC’s technology will be able to support NTP development efforts by providing the research tools and insight required to understand water submersion accidents in LEU-NTP systems. Before the Phase 1, little work had been conducted on the water submersion in LEU NTP systems and a great deal was learned. After Phase 2, USNC will have a much greater understanding and modeling capabilities that will assist in NASA NTP development efforts.

Beyond NTP the technology and expertise that USNC is building has application to small nuclear systems for surface power and science missions.

Potential Non-NASA Commercial Applications

The market for NTP systems and their supporting technologies extend beyond NASA with numerous potential customers in private industry and defense field. NTP is a game changing technology and it is difficult to quantify this non-NASA market but it has the potential to be very large.

USNC is pursuing earth based mobile reactors and small modular reactors. These reactors are different than traditional reactors as they can be shipped in whole or modular sections. In shipment of these reactors it is essential to ensure that they are subcritical during water submersion (much like space reactors). The technology developed in this SBIR may have application in addressing water submersion in these earth-based reactors.

In addition, a number of other companies are trying to bring mobile or small modular reactors to the market and the novel technology developed in this SBIR might find a market here. The market potential for advanced reactors is several billion dollars and approximately 40 U.S. companies are trying to bring advanced nuclear technology to the market backed by total of more than 1.3 billion dollars of private investment. USNC’s submersion safe control technology can address the needs of this emerging market.

Technology Taxonomy Mapping

• Sources (Renewable, Nonrenewable)
• Spacecraft Main Engine