The demand for mobile power generation and low-cost durable and yet efficient and low emission engines is ever increasing. This work focuses on the aerodynamic characteristics of a novel combustion engine - the wave disc engine. This new core technology uses a turbo combustion shock wave technique to efficiently convert fuel sources to mechanical power and subsequently electrical power. In such engines, sudden closing of the flow passage is used to generate shock wave that can enhance combustion and allow for compression and expansion of the operating gases. This new engine concept combines the advantages of (a) high efficiency confined combustion comparable to automotive internal combustion engines (IC-E) and cutting-edge pulse detonation engines (PDE), with (b) the high power density and low maintenance of continuous flow gas turbines (GT), but (c) at a much lower unit cost due to its physical simplicity and compactness. This work performs a detailed thermodynamic analysis of a Wave Disc Engine by taking a single channel as the control volume as well as a full rotor. The analysis gives the general expression of the net work done by the flow and the thermal efficiency in terms of the mass-average properties, and states that under some certain conditions the operation can achieve the efficiency of Humphrey cycle. Two one-dimensional numerical codes were created using TVD-MacCormack scheme and Gottlieb-Turkel scheme to provide an estimation of the ports timing for multi-dimensional design. A simple arc was chosen as the channel shape of the baseline engine. After some geometric adjustments, the configuration of the baseline design was determined. However, its efficiency is very low. Energy losses were investigated by a 2D simulation of a single channel. The results showed that the significant outgoing kinetic energy and the under-expansion of the exhaust gas were the main sources of energy loss. To improve the performance of the energy extraction by the curved channels, the mechanism of the torque generation by the expansion wave was studied and the principle for the channel shape design was obtained. Several channel shapes were proposed and tested. Eventually the convergent channel was chosen as the best design and implemented on a full engine. The results showed that the efficiency of the engine increased from 2.2% to 3.3% by using the convergent channel. Then the effects of the peak pressure in the channel and of the tip speed on the engine power and efficiency was investigated. Two methods to reuse the energy from the exhaust gas were proposed - adding a return channel or an external turbine. It was proved by the simulations that both methods can improve the efficiency and adding an external turbine is more effective. At last, various plans to prevent the leakage going into the inlets were compared and the jagged wall design was found to be the best.
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