In this work, the empirical correlations for viscosity and temperature of biodiesel fuels have been optimized. In order to achieve this, an optimized empirical correlation is proposed and the predicted values are found to be in good agreement with the experimental data. The optimized empirical correlation has the advantages of small relative error, small error range and no obvious error fluctuations. On the basis of the proposed correlation, the concepts of viscosity gradient of biodiesels and critical preheating temperature of biodiesels are proposed in this paper. The viscosity gradient, the critical preheating temperature and the range of applications for three kinds of biodiesel fuels are obtained by analyzing their viscosity data.

中文翻译：

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生物柴油燃料运动粘度预测的优化模型▴

在这项工作中，已经优化了生物柴油燃料的粘度和温度的经验相关性。为此，提出了一种优化的经验相关性，并发现预测值与实验数据非常吻合。优化的经验相关性具有相对误差小，误差范围小，误差波动不明显的优点。在此基础上，提出了生物柴油的粘度梯度和生物柴油的临界预热温度的概念。分析了三种生物柴油的黏度数据，得出了三种生物柴油的黏度梯度，临界预热温度和适用范围。