This paper proposes a novel virtual engine calibration method for alternative fuels using thermodynamic simulation for in-cylinder pressure prediction. Based on known engine data, including the crank angle of the peak cylinder pressure, the optimization problem is defined for a desired indicated mean effective pressure. The decision variables are the combustion and heat transfer model parameters The method was tested for three different engines of different sizes, operating with ethanol, hydrogen and natural gas, and different equivalence ratios. The Wiebe model and a quasi-dimensional fractal combustion model were compared. The results showed that the method was able to successfully predict the in-cylinder pressure curve, with a coefficient of determination higher than 0.99. Furthermore, the method predicted the peak pressure and the crank angle corresponding to 50% of mass fraction burned with a maximum deviation of 2.5% and 1.5 °CA, respectively.

中文翻译：

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使用乙醇、氢气和天然气作为替代燃料的发动机的基于气缸压力的校准模型

本文提出了一种新颖的替代燃料虚拟发动机标定方法，利用热力学模拟进行缸内压力预测。基于已知的发动机数据，包括峰值气缸压力的曲柄角，针对期望的指示平均有效压力定义优化问题。决策变量是燃烧和传热模型参数。该方法针对不同尺寸、使用乙醇、氢气和天然气以及不同当量比的三种不同发动机进行了测试。对 Wiebe 模型和准维分形燃烧模型进行了比较。结果表明，该方法能够成功预测缸内压力曲线，决定系数高于0.99。此外，该方法还预测了燃烧质量分数 50% 对应的峰值压力和曲柄角，最大偏差分别为 2.5% 和 1.5 °CA。