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As an important means of engine development and optimization, modelbuilding plays an increasingly important role in reducing carbon dioxide emissions of the internal combustion engines (ICEs). However, due to the non-linearity and high dimension of the engine system, a large amount of data is required to obtain high model accuracy. Therefore, a modelling approach combining the experimental data and prior knowledge was proposed in this study. With this method, an artificial neural network (ANN) model simulating the engine brake specific fuel consumption (BSFC) was established. With mean square error (MSE) and Kullback-Leibler divergence (KLD) serving as the fitness functions, the 86 experimental samples and constructed physical models were used to optimize the ANN weights through genetic algorithms.

This study investigates the influence of leakage through the apex seal, fuel type and recess size on the performance of a Rotary Engine. A commercial CFD software, Fluent, was applied and a two-dimensional model was constructed to predict the engine performance. Air and fuel flow into the chamber by two separate ducts in this model were used to simulate fuel-air mixing. Three different apex seal clearances (0mm, 0.4mm, 0.5mm) were simulated. The computations with two types of fuel, CH4 and C8H18, were performed and put in result comparison in this study. The recess sizes were based on three compression ratios, 8.33, 9.55 and 10.18. To simplify rotor mesh construction in the model with leakage, a porous region was generated to model this quite small gap. The generation of a porous region can greatly reduce mesh sizes and stabilize the numerical iterations.

This article is to investigate the inlet and exit pipe effect on a rotary engine performance. A 1-dimensional, three-cylinder reciprocating engine model was adopted to simulate the operation of a rotary engine with three separate chambers. The chamber volume variation in this model was identical to a real rotary engine. The test data of the real rotary engine were used as a benchmark test for this model. Various parameters are then studied, including pipe length, pipe diameters, and pipe shape with convergent/divergent angles. In the performance analysis, the results showed that the averaged performance data (BSFC, brake work, brake torque, pressure distribution) was within 5 % in tolerance. The results of pipe length variation showed that in a range of short inlet pipe brought higher power (8.4 %). On the contrary, the exhaust pipe had a better work output over a certain length (10%). With a shorter inlet pipe and a longer exhaust pipe, the work output makes about 14.3% higher.