Experimental and simulated study on the ignition delay time of dimethyl ether-heptane/oxygen/argon mixtures

摘要

The addition of oxygenated fuels to fossil fuels has been considered as a promising approach for reducing the issues associated with hazardous substances. The ignition delay time data of dimethyl ether-heptane mixtures were obtained using a shock tube under the following conditions: pressures of 0.8, 4.5, and 10 atm; equivalence ratio of 1; temperature within the range of 1171-1571 K; and dimethyl ether proportion within the range of 0-100%. The Arrhenius dependence of the ignition delay times on temperature and pressure was fitted. The experimental results show that the ignition delay times of dimethyl ether-heptane mixtures are less than those of pure dimethyl ether and pure n-heptane within a certain blending ratio range. A combined model named "blended model" was proposed based on the LLNL n-heptane version 3.1 and Zhao dimethyl ether models. The effect of DME addition on the IDT of the fuel mixtures was investigated using the blended model in detail.