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A good understanding of the thermophysical properties of hydrocarbon fuels at supercritical pressure is important to research on experiment and numerical simulation of fuel supercritical spray. Experimental measurements are difficult to conduct directly because of the extremely high pressure and high temperature. In this study, back propagation (BP) neural network, BP optimized by mind evolution algorithm (MEA-BP) and BP neural network optimized by genetic algorithm (GA-BP) are established to determine the nonlinear temperature-dependent thermophysical properties of density, viscosity, and isobaric specific heat (C p ) of hydrocarbon fuels at supercritical pressure. Meanwhile, approximate formulas for these properties prediction are primarily proposed using polynomial fitting. In this paper, models that can predict three types of physical properties of three kinds of hydrocarbon fuels and their mixtures in a wide temperature range under supercritical pressure are established. In the prediction of density and C p , BP neural network has a good prediction effect. The results show that the MAPE is lower than 2% in the prediction of density and C p , but the MAPE of viscosity prediction is slightly higher than 5% using BP. Furthermore, MEA and GA are used to optimize the prediction of viscosity. The optimization effect and computation of the MEA is better than that of GA because MEA does not have the local optimization and prematurity problems. The present work offers an efficient tool to predict the thermophysical properties of hydrocarbon fuels over a wide range of temperatures under supercritical pressure which can be easily extended to other fuels of interest. It will be beneficial to the experiment and numerical simulation studies of supercritical sprays.

Abstract. This paper introduces the teaching method and practice of "intelligent instrument principle and its application" course, which are all-round and configurable changes based on embedded technology. The full text regard "Intelligent instrument principle and Its Application " as "new engineering" in the "application" course, the embedded technology through the "smart instrument principle and its application" course core content, including intelligent chip embedded technology, Interface embedded technology, communication methods can be embedded technology and software can be embedded technology, so that the curriculum has become one of the first-class student training platform.