Creare addresses critical issues across a breadth of power systems and related engineering technologies. Our experience encompasses scales ranging from large power plants to compact portable units and applications from deep oceans to outer space. We work in generation of power as well as its efficient transmission, storage, and ultimate usage. Our focus can range from detailed design and prototyping of a specific component to overall thermodynamic analysis of alternative system configurations. While some of our assignments simply result in reports and studies, most culminate in the construction and testing of laboratory or fieldable prototypes.

Examples of our work include:

  • Design, construction, and testing of an ammonia/water bottoming cycle for gas turbines based on a recuperated Rankine cycle.
  • Development of evaporators and condensers for alkali metal thermal-to-electric conversion cells.
  • Evaluation of a pressure-recovery concept for gas turbine power plant exhaust.
  • Development of heat exchanger technology for a pressurized-air energy storage system.

Creare analyzes, develops, and tests combustion processes and equipment for applications ranging from power generation to propulsion. Our core capabilities encompass analysis of flow, heat transfer, and kinetics—including conventional and novel CFD approaches—and design, prototyping, and testing of small-scale (< 20 kW) combustion devices and instrumentation.

Much of Creare’s recent work in combustion has been focused on air-breathing propulsion, with an emphasis on gas-turbine engines, augmenters, and scramjets. Another area of interest includes small-scale devices that run on heavy, low volatility fuels for applications such as combat feeding and portable tactical power systems.

Some examples of Creare combustion projects include:

  • A recuperated, multifuel burner for a Stirling engine power system.
  • A control system for small diesel generators that reduces emissions and maintenance intervals.
  • Novel fueling systems for enhancing augmenter combustion stability.
  • Instrumentation for three-dimensional imaging of fuel sprays.
  • A high-efficiency burner and appliances for military field kitchens.
  • Compact fuel reformer systems for converting jet fuel to syngas in small devices.
  • Custom CFD-based software tools for predicting combustion stability.
  • Compact gas turbine combustors for inter-turbine burning.
  • Passive optical sensors for measuring heat release and fuel distribution in realistic combustion systems.
Single-person portable Brayton power system.

Single-person portable Brayton power system.

Creare is an innovative developer of advanced technology for compact power systems. Small systems are inherently challenging due to fundamental scaling penalties and fabrication constraints. For these reasons, Creare has focused intense effort for decades on the development of small turbomachines, heat exchangers, and thermodynamic systems. The resulting technology, expertise, and equipment enable us to address a wide variety of unique applications with very demanding requirements.

Current or recent projects include:

  • 500 We closed-loop Brayton system that is powered by JP-8 combustion and is single-person portable.
  • 1 kWe closed-loop Brayton system to be powered by a fission reactor for space applications.
  • 10 kWe closed-loop Brayton system for high-altitude aircraft.
  • 8 kWe Rankine bottoming system that converts waste heat into electric power without burning fuel.
  • 20 kWe Rankine system powered by heat from deep sea hydrothermal vents.
  • Performance enhancements for military diesel cycle generators.
  • Industrial expander for natural gas pipelines.
  • Ultra-compact alternator technology for military applications.
  • Plasma gasification system for waste-to-energy conversion.

Creare develops innovative fuel cell components and systems, primarily for lightweight portable power applications. Our work in this area has its heritage in prior Creare development of alkali metal thermal-to-electric conversion (AMTEC) systems and compact high-performance heat exchangers. Creare’s fuel cell work focuses on stack design, system optimization, and control of thermal-fluid material balances in the cell.

Examples of innovative fuel cell technology developed at Creare include:

  • Thermal and fluid management systems for prototype fuel cells.
  • Innovative sensors and techniques for methanol concentration control in direct methanol fuel cells.
  • In cooperation with corporate partners, Creare has demonstrated compact, lightweight direct methanol fuel cells and polymer electrolyte membrane (PEM) fuel cells with potential use in portable power systems.
  • Demonstration of a compact hydrogen generator for portable PEM fuel cells.
  • Very high efficiency (98%) water recovery and recycling systems for solid oxide fuel cell/reformer systems used for portable power generation.
  • Low-cost, high-efficiency humidifiers for PEM fuel cell systems.
ITB engine test

Engine Test of an Inter-Turbine Burner Concept.

Creare’s engineers are actively engaged in a broad range of propulsion research, with a focus on air-breathing propulsion.  Our primary areas of interest include gas turbine engines and augmentors, spark ignition engines, and scramjets. Our contributions in these areas have included development of novel combustors such as inter-turbine burners, modeling of ignition, fuel spray, and combustion processes, development of novel fuel injectors and fueling systems, development of instrumentation for combustion research and active combustion monitoring and control, and development of high temperature heat exchangers for gas turbine engines.

Examples of our work include:

  • Novel fueling systems for enhancing augmenter combustion stability.
  • Instrumentation for three-dimensional imaging of fuel sprays.
  • Custom CFD-based software tools for predicting combustion stability.
  • Compact gas turbine combustors for inter-turbine burning.
  • CFD tools for modeling fuel sprays and ignition processes in gas turbine combustors.
  • Passive optical sensors for measuring heat release and fuel distribution in realistic combustion systems.
  • Recuperators for fuel-efficient UAV propulsion.
  • Development of cooled probes for application of optical diagnostics in combustors.
  • Development of sensors and actuators for scramjet flow and combustion control.
Thermophotovoltaic power system assembled for testing.

Thermophotovoltaic power system assembled for testing.

For over 40 years, NASA has used nuclear-powered thermoelectric generators to provide electric power for a range of space exploration missions. Creare engineers are working with NASA on alternative technologies that promise to improve power conversion efficiency and reduce the weight and cost of next-generation power systems. Creare is developing both static and dynamic systems with potential to improve conversion efficiency by a factor of two to four and reduce weight by a factor of two to three.

Creare’s ongoing work with static systems is primarily focused on thermophotovoltaics to convert radiant energy from a radioisotope heat source directly into electricity. The technical challenges for this concept include the fabrication of high-temperature (1200 K) selective emitter structures and the thermal design, development, and fabrication of converter hardware, advanced photovoltaic cells, and advanced optical filters to maximize efficiency.

Creare is also developing dynamic power conversion systems based on the closed-loop Brayton cycle. These systems use miniature turbomachine technology to compress and expand the working gas. The key technical challenge for these systems is to fabricate small high-speed turbomachines with a high-temperature (1100 K) turbine and a low-temperature (350 K) compressor joined in a common rotor assembly supported by maintenance-free gas-bearings.