USAF researches REL Skylon/Scimitar tech for hypersonic aircraft

[DocM]

USAF is looking to use Reaction Engines Ltd.'s (UK) SABRE and SCIMITAR engine precooler for high Mach flight engines. 

 

SDC broke it:

 

http://www.space.com/32115-skylon-space-plane-engines-air-force-vehicle.html?cmpid=514648

 

The REL precooler tech  was given a thumbs up by the USAF Research Lab (USAFRL) last year, and REL is now partnered with BAE Systems which now holds 20% of REL. The USAFRL cooperation with Reaction Engines is continuing under a Cooperative Research and Development Agreement. USAFRL is headquartered at Wright-Patterson Air Force Base in Ohio.

 

The SBIR (Small Business Innovation Research) posting says the desired performance is to precool incoming air by at least 500°F at 55,000 feet. REL's precooler has precooled air from 1,832°F  (1000°C) down to -238°F (-150°C) in 10 milliseconds with no frosting. It also mentions the possibility of commercialization.

 

This appears similar to REL's SCIMITAR boosted turbo-ramjet engine

 

 

PopSci story on SCIMITAR
http://www.popsci.com/military-aviation-space/article/2008-01/green-skies-mach-5

 

For takeoff, landing and subsonic flight, the A2's Scimitar engine sends intake air through a bypass duct [1] and into a turbine [2], like a standard jet engine. After reaching supersonic speed, though, the engine redirects air from the bypass duct through the engine core [3] for flight up to Mach 5. Like a ramjet, the Scimitar works by taking in air from the atmosphere at high speeds and funneling (or "ramming") it until it's intensely compressed. At this point, the extremely hot air mixes with fuel and causes ignition. But the Scimitar one-ups traditional ramjet design by adding a turbine [4] that compresses the incoming air even further. Ramjets usually can't use turbines because the incoming air is so hot that it will melt the turbine blades. The Scimitar solves that problem by first cooling the air in a heat exchanger [5] using gaseous helium.

 

SBIR solicitation 

 

https://www.sbir.gov/sbirsearch/detail/870285

 

Durable Pre-cooling Heat Exchangers for High Mach Flight

 

Agency: Department of Defense
Release Date: December 10, 2015
Branch: n/a
Open Date: December 10, 2015
Program / Phase / Year: SBIR / Phase I / 2016
Application Due Date: February 17, 2016
Solicitation: DoD 2016.1
Close Date: February 17, 2016
Topic Number: AF161-074
Description: TECHNOLOGY AREA(S): Air Platform

 

The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with section 5.4.c.(8) of the solicitation and within the AF Component-specific instructions. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws. Please direct questions to the AF SBIR/STTR Contracting Officer, Ms. Gail Nyikon, gail.nyikon@us.af.mil.

 

OBJECTIVE: Enable turbomachinery operation in excess of Mach 4 by pre-cooling the incoming air. Utilize modern materials, manufacturing, and design processes to design a durable pre-cooling heat exchanger.

 

DESCRIPTION: Throughout the past 50 years, there have been multiple efforts to develop a single air-breathing engine that is capable of thrust from takeoff up to Mach 4 speeds and faster. A major challenge in developing this capability is the hot air that is ingested at high Mach speeds. There have been attempts dating back to the 1960s to solve this problem by using a pre-cooler heat exchanger in front of the air compressor face to reduce the temperature of the incoming air. It is expected that high Mach flight will be growing in importance for the Air Force to execute its five core missions and that precooled propulsion could be an enabler for new platform capabilities. The objective of this topic is to mature the technology for a lightweight and compact pre-cooler heat exchanger for high Mach propulsion that uses turbomachinery.
No pre-cooling heat exchanger has ever been flown. The biggest difficulty is getting the heat exchanger light weight and compact enough to be practical for flight. In many industries, modern manufacturing has allowed for lighter weight components and unique geometries to be built. 

 

This topic will leverage modern manufacturing techniques (e.g., additive manufacturing, friction stir welding, C&C milling, etc.) to develop a pre-cooler heat exchanger that is practical to be used in a propulsion system on a high Mach flight system. At the end of the Phase II, it is expected to fabricate a scaled prototype of the heat exchanger and conduct initial evaluation testing. Throughout this topic, it is important to address thermal integration for the necessary systems involving the heat exchanger.

 

Important attributes of pre-cooler heat exchangers (of roughly equal importance) that need to be addressed include durability, affordability, ability to integrate with propulsion and flight systems, scalability, manufacturability, impact on ground operations, material and manufacturing maturity, amount of pressure drop across the heat exchanger, and maintainability. The pre-cooler should be able to cool incoming freestream air to about 500 degrees F or cooler for flight conditions at altitudes above 55,000 feet. It is also expected the heat exchanger to be developed will have a specific power of at least 15kW/lbm.

 

Both Phase I and Phase II will consist of an appropriate level of design and systems engineering efforts to understand what it will take to fully develop the proposed solution. These efforts should address all issues but focus on the demonstrations that will be performed in Phase II. Modeling of the heat exchangers performance and its integration is needed throughout both phases to understand its potential. Recommend developing one or more reference vehicle platform designs for one or more Air Force core missions to show how the heat exchanger could enable that capability.

A letter of endorsement from a Versatile Affordable Advanced Turbine Engines (VAATE) participant is highly encouraged.

 

Commercialization of the pre-cooler heat exchanger involves integration of the pre-cooler into high-speed propulsion systems for DoD and/or commercial needs such as point to point cargo and access to space.

 

Commercialization of the heat exchanger can also be used for propulsion thermal management and terrestrial applications.

Remote access to the DoD Supercomputing Resource Center (DSRC) to cleared personnel will be made available if needed.

 

PHASE I: Conduct initial design of the pre-cooler heat exchanger with an emphasis on its integration and manufacturing. Based on higher level platform requirements, derive requirements for the heat exchanger components that have early verification and validation. Develop plans for the Phase II fabrication and testing.

 

PHASE II: Fabricate a scaled prototype of the heat exchanger utilizing the proposed manufacturing approach. Conduct testing in a relevant laboratory environment. Develop and validate performance and lifting models based on the testing. Utilize this information to increase the understanding of how the heat exchanger integrates into a platform or platforms.

 

PHASE III DUAL USE APPLICATIONS: Phase III will focus on maturing the heat exchanger and beginning to integrate it into a full propulsion system and a vehicle platform. Additional Phase III activities can consist of applying the heat exchanger and its manufacturing to other defense and commercial domains.

 

REFERENCES:

 

Murthy, S.N.B., "Developments In High-Speed Vehicle Propulsion Systems," AIAA, 1996.

Balepin, V., et.al., "Combined propulsion for SSTO rocket - From conceptual study to demonstrator of deep cooled turbojet," AIAA 96-4497.

 

Taguchi, H., et.al., "Performance Evaluation of Hypersonic Pre-Cooled Turbojet Engine," 20th AIAA International Space Planes and Hypersonic Systems and Technologies Conference, AIAA 2015-3593.

 

Ahren, J.E., "Thermal management of air-breathing propulsion systems," 30th Aerospace Sciences Meeting and Exhibit, AIAA 92-0514, 1992.

 

Murray, J.J., et.al., "An Experimental Precooler for Airbreathing Rocket Engines," 48th International Astronautical Federation Congress Melbourne, Australia 1998, IAF-98-S.5.02.

 

KEYWORDS: high mach, precooling, precooler, heat exchanger, thermal, materials, manufacturing, design, propulsion, hypersonic

[Unobscured Vision]

Call me crazy, but I see a possible spin-off of this tech -- super-chilling extremely hot air to prevent reentry overheating of spacecraft.

 

Obviously it would make these spacecraft insanely heavy though ... hmm. A superchilling system like this isn't exactly lightweight. Needs more thought.

[DocM]

1) Reaction Engines will soon sign a Phase 3B SABRE engine development contract with ESA. It's said this is to cut metal for a test engine.

 

2) 2 new managers via Lockheed Martin and Safan (Ariane 6)

 

Quote

Reaction Engines Ltd., a UK based company developing a new class of aerospace engine, today announces the strengthening of its leadership team with two senior management appointments and the establishment of a US-based subsidiary to lead its engagement with potential US government and industry partners.

The company has appointed Mark Wood to the newly created role of Chief Operating Officer & Engineering Director, with responsibility for operational leadership, improving the efficiency and effectiveness of the business through integration, collaboration and operational best practices.

Mark Wood joins Reaction Engines from Safran Power UK, where he most recently held the position of Engineering Director, with responsibility for Safran Power Engineering in the UK and for engineering services across the whole Power division. He will report to Mark Thomas, Reaction Engines Chief Executive Officer.

He will shape the companys organisational development for the future and take on functional leadership of the Engineering Team, enabling Richard Varvill to focus on Chief Engineering the SABRE engine & technologies.

Mark Thomas said I am delighted to welcome Mark Wood on board. He has over 20 years experience in the aerospace industry and a very relevant and impressive track record of successfully delivering complex engineering programmes. He brings additional strength to Reaction Engines leadership team as we continue to grow the Company. Mark has hit the ground running and is integrating well. I look forward to working with him and know that his energy and experience will have a positive effect on everyone.

Mark Wood said I am really excited to be joining Reaction Engines. The technologies that have been developed to date are truly cutting edge and I am delighted to be able to be part of the future growth of the company. I look forward to working with Mark Thomas and the team as we continue on this exciting journey.

Reaction Engines has also established a new US-based subsidiary, Reaction Engines Inc. to support the expansion of the companys development efforts and lead engagement with potential US government and industry partners.
The company has appointed Dr. Adam Dissel, an aerospace leader with over 15 years experience in the development of advanced vehicle systems, to lead the new subsidiary as President of Reaction Engines Inc. Dr. Dissel joins Reaction Engines Inc. from Lockheed Martin Space Systems where he served as System Architect for Responsive Space. He will report to Mark Thomas, Chief Executive Officer of Reaction Engines Ltd.

Mark Thomas commented The establishment of a US office is the obvious next step for us, building on excellent work done under a collaborative R&D agreement with future export markets in mind. I am delighted that Adam has joined the team as President of Reaction Engines Inc. His skillset, experience and strong customer focus is very relevant to the task ahead and I look forward to working together to grow this part of our business.

Dr. Adam Dissel, President of Reaction Engines Inc., said I have followed the impressive progress of Reaction Engines and the SABRE engine with great interest for many years, and I am thrilled to now join such a fantastically skilled group of people and work towards future development and partnership opportunities in the US. The SABRE engine class is the most exciting new evolution in propulsion in decades and I am eager to advance the applications where these technologies could result in breakthrough system capabilities in high-speed flight and space access.