DIFFUSION BONDED AERO HEAT EXCHANGER (DBAHx)

Transcription

1 DIFFUSION BONDED AERO HEAT EXCHANGER (DBAHx) The consortium Organisation Name Enterprise Category Responsibility Meggitt Control Systems (Lead) Large (UK) Design / Analysis and Testing Precision Micro Ltd Large (UK) Aluminium Chemical Etching The Open University University / RTO Aluminium Diffusion Bonding S&C Thermofluids Vacuum Furnace Engineering Small SME Medium SME CFD Aerothermal Analysis of Complex Flows Furnace Design and Industrialisation Modelling Project summary Current development in aircraft propulsion will result in significantly increased demand for both recuperation and rejection of thermal energy. Major drivers include Ultra High Bypass Ratio (UHBR) engines which are being developed for significantly improved aero fuel efficiency, resulting in more heat to manage in a reduced space envelope and reduced fuel flow for cooling. The project objective was to design and manufacture a solid-state bonded aerospace heat exchanger from chemically etched aluminium plates. The project researched advances in CFD analytical methods for complex heat transfer surfaces, etched fluid channels and solid state bonding of aluminium, and produced demonstration units achieving advanced heat transfer, lower weight and lower cost of manufacture. The benefits of this technology include enabling the heat exchanger to utilise the available engine space to greater effect, and meeting the high pressure and heat rejection demands of next generation aero engines. Etched Plates Stacked Etched Plates Diffusion Bonding Tensile Test Coupons & DBAHx Core Figure 1 - Illustration of the DBAHx Manufacturing Process 1 Copyright Aerospace Technology Institute. 2017

2 Figure 2 Simplified Flow Schematic The project commenced in October 2015 and brought together the expertise of 4 industrial partners and 1 academic partner. The DBAHx project was led by Meggitt Control Systems, with 3 other industrial partners; Precision Micro, S&C Thermofluids, and Vacuum Furnace Engineering (VFE). The project completed in March In the final stages of the project, Meggitt produced demonstrators for validation testing which enabled the technology to be demonstrated to TRL4. VFE has produced concepts for the industrialisation of the diffusion bonding technology. Table 1: Summary of the project grant details Project Funding Lead Partner No. of Partners Total: 0.87m Meggitt Control DBAHX Grant: 0.39m Systems 5 Partner Composition 3 Large Enterprises 1 SME, 1 University Duration 10/ /2017 Table 2: Summary of the project focus areas ATI Value Streams ATI Enablers ATI Attributes Strategic Horizon Whole Aircraft Aerodynamics Safety Secure Structures Manufacturing x Cost x Exploit Propulsion x Materials x Environment x Position x Systems Infrastructure Fuel Burn x Process and Tools x Operational Needs Passenger Experience 2 Copyright Aerospace Technology Institute. 2017

3 Technology achievements: The DBAHx project consisted of 7 work packages focused on developing the technology. The technology at the end of the project has been proven to TRL4. Table 3 Work Package Descriptions Work Package Partners Key Outputs WP1 Design & Analysis Meggitt and S&C Chemically etched channel concepts heat transfer and pressure drop characterisation. CFD and 1D parametric design tools. WP2 Aluminium Chemical Deep aluminium chemical etching. Precision Micro Etching Geometric control and process control defined. WP3 Design Realisation Meggitt Fuel oil heat exchanger application designed for manufacture and test. WP4 Aluminium Diffusion Bonding Open University and Meggitt Aluminium diffusion bonding achieved, and key design rules defined. WP5 Demonstrator Manufacturing Meggitt Demonstrators manufactured and sent for testing WP6 Testing Meggitt Performance, pressure and low cycle fatigue testing successfully performed on the demonstrators. WP7 - Industrialisation VFE Concepts for high volume aluminium diffusion bonding have been developed. The technology application selected for the DBAHx demonstrator is a high fuel pressure fuel-oil heat exchanger application. This application was selected due to the arduous operating environment with high fuel pressure and a high number of pressure cycles in the duty cycle. The aluminium diffusion bonding technology enables joining of the etched plates. The flexible design offered by the chemical etching process enables the heat exchangers to be designed and manufactured to achieve the operational requirements and perform the heat transfer duty in a smaller volume and lower weight, with an estimated space envelope and weight saving of 20% for the application selected. Shell & Tube Hex (Past) DBAHx Demonstrator (Current) Table 4: Summary of the technology achievements Project Performance Improvements Progression Component weight reduction Parametric design tools have been Volumetric reduction created to link the concepts to CFD Increased pressure capability vs current Representative sub scale demonstrators DBAHx FOHEs have been lab tested to prove out the Significant component part count technology concepts reduction 3 Copyright Aerospace Technology Institute. 2017

4 Figure 3 CFD Analysis of the Complex Flow Channels 4 Copyright Aerospace Technology Institute. 2017

5 Economic impact: The project has been a key part of Meggitt s development of their thermal systems Applied Research & Technology strategy. This project has supported the successful application for the ATI and Innovate UK part-funded Ultra High Bypass Ratio Thermal Systems (UHBR Thermals) Project. Meggitt have also announced a 130M investment in a new site at Ansty Park in Coventry. The site will include an engineering and manufacturing Centre of Excellence for future aerospace thermal systems technology; Tony Wood, Chief Operating Officer, said: We are proud of our heritage, both in the UK and here in the Midlands, which has underpinned our ability to secure strong market positions on new aircraft programmes. This planned new facility, adjacent to the Manufacturing Technology Centre and Advanced Manufacturing Training Centre, marks a major advance in the development of our global manufacturing footprint and strategically positions us for sustainable growth. By bringing world-class innovation and operational delivery together on this site we will accelerate Meggitt s ability to meet the current and future needs of our customers worldwide. This project has enabled the Open University to upgrade their diffusion bonding facilities and the state of the art facilities have enabled the Open University to demonstrate their world leading capabilities in diffusion bonding. As a research services provider, S & C s business plan relies heavily on finding new and repeat customers for CFD and experimental services within a range of engineering industries. DBAHx has facilitated this plan by building a strong working relationship between Meggitt and S&C. S&C have also recently provided experimental test facilities to other parts of Meggitt which resulted in the successful completion of a key project for Meggitt. S&C s involvement in DBAHx provides the opportunity to demonstrate its CFD capabilities to the ATI community previous ATI projects have focussed on S&C s experimental testing expertise. This project has led to the expansion of Vacuum furnace Engineering s R&D strategy, leading to the employment of their first design apprentice, with further plans to increase R&D personnel to 4 team members. Next steps for the DBAHx technology: The DBAHx project has been followed by the UHBR Thermals project (part funded by the ATI and Innovate UK) which enables the DBAHx technologies to be matured to TRL6 and MCRL4. The DBAHx technologies, solid state bonding and chemical etching, will be developed further to enable even greater performance gains via optimisation of the channel geometries, integration of headers, shaping of the heat exchanger geometry and low-cost manufacturing techniques. The manufacturing technology for the DBAHx will be matured within the UHBR Thermals programme and the chemical etching technology will be a key part of that. Precision Micro have launched a secondary project to develop a dedicated aluminium etchant and process, which will support the maturation of the aluminium chemical etching process. The diffusion bonding industrialisation concepts developed by Vacuum Furnace Engineering will also be matured within the project and integrated with a robust production line concept. 5 Copyright Aerospace Technology Institute. 2017

6 Partners future exploitation: The DBAHx concept has market winning attributes for fuel oil heat exchangers across a number of applications and concept designs have been produced for one large civil engine manufacturer s future engine programme with discussion around the DBAHx concept being tested on a ground test engine in early S&C Thermofluids is also a partner on the UHBR Thermals project, which will provide the company with the opportunity to expand its understanding of heat exchanger design and prediction to include more complex channel geometries and the design of integrated fluid headers. This expertise is applicable to heat exchangers outside the aerospace industry and S&C will be engaging with manufacturers within the oil & gas and nuclear sectors to promote this capability to a new market area. The Open Universities state of the art facilities have led to attracting and accomplishing other successful projects beyond DBAHx. Vacuum Furnace Engineering has submitted a patent for a novel diffusion bonding concept and will be expanding their R&D capabilities in the future. [ENDS] 6 Copyright Aerospace Technology Institute. 2017