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This paper presents the performance-cycle analysis of a dual-spool, separate-exhaust turbofan engine, with an interstage turbine burner (ITB) serving as a secondary combustor. The ITB, which is located at the transition duct between the high-and the low-pressure turbines, is a relatively new concept for increasing specific thrust and lowering pollutant emissions in modern jet engine propulsion. A detailed performance analysis of this engine has been conducted for steady-state engine performance prediction. A code is written and is capable of predicting engine performances (i.e., thrust and thrust specific fuel consumption) at varying flight conditions and throttle settings. Two design-point engines were studied to reveal trends in performance at both full and partial throttle operations. A mission analysis is also presented to ensure the advantage of saving fuel by adding ITB.

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Locating hotspots in metal engine components can be used as an impetus to design a better cooling system. This study focuses on a numerical investigation of a three-dimensional (3-D) transient heat transfer process for a Ford 5.4-L V8 engine. A 3-D transient finitevolume method to solve the heat conduction equation is presented first. This is followed by the implementation of the coupling equations at the gas-solid interface into the KIVA code. The numerical model is validated by a one-dimensional heat conduction problem. Finally, 3-D simulation of the Ford engine with conjugate heat transfer mode is presented and discussed.

Heat transfer is one major important aspect of energy transformation in spark ignition (SI) engines. Locating hot spots in a solid wall can be used as an impetus to design a better cooling system. Fast transient heat flux between the combustion chamber and the solid wall must be investigated to understand the effects of the non-steady thermal environment. This study investigates numerical simulation of 3D transient heat diffusion phenomena in solid, exposed to steady and unsteady thermal boundary conditions. A 3D transient finite volume method to calculate heat transfer across a solid medium will be presented first. It is then validated with steady state thermal boundary conditions. The validation extends to the effects of multiple solid materials for which large thermal property difference is investigated. Finally the effects of non-steady thermal boundary environment are discussed. Numerical results are validated with available analytical solutions and are compared with FLUENT result.