I. Mitchell, Rolls-Royce plc, Derby, United Kingdom; D. Clark, University of Birmingham, Birmingham, United Kingdom
Aerospace requires heat treatment of structurally complex components. Localised processing of non-uniform surface geometries presents significant technical challenges. The novel heating technique described, precisely maintains temperature tolerances across target regions. The author presents the development of a heating technology using inert gas jets. This Rolls-Royce patented system (GB05121854.3) is applied to representative component geometry. Turbulent impingement jets offer high heat transfer, at the expense of sensitivity to variations in stand-off. The approach detailed, discusses the use and advantages of laminar jets for components with intricate forms. These provide a more robust process with reduced component geometric sensitivity. The author investigates the design and process sensitivity of this method using computer modelling, validated through experimentation. Computational fluid dynamics (CFD) has been used to aid design from a fluid flow perspective. While finite element (FE) techniques are used to assess of the applicability of the system for different component sizes and locations.
Summary: The paper presents the description and development of a novel method of locally heating componentsusing inert gas jets. Processing components in this way allows tight temperature tolerances to be achieved in thin sections. The technology has the advantage that it utilises inert atmosphere media and is less susceptible to variations in stand-off distance than competing technologies.
The use of gas jets allows one to control the heating pattern and scale the technology for various heating requirements.
