Numerical Simulation On Non-catalytic Coke Of Hydrocarbon Fuel

Endothermic hydrocarbon is the first choice for hypersonic vehicle coolant fuelby considering the security, development costs, the endothermic effect of fuelutilization and structural design. Hydrocarbon fuels in high temperature coolingchannel are susceptible to cracking the endothermic process of coke. Coke is a highmolecular weight hydrocarbon mixtures, has the characteristics of viscosity and highboiling point, causing a lot of coke to stick on the wall, difficult to erosion, affect thecooling effect, resulting in great harm. Coking is a major problem for hypersonicengine cooling technology. The coke can be divided into the thermal oxidation ofcoking and cracking of coke. Working environment due to the cooling channelshigher than400℃, the coke is cracking coking, in which cracking coking can bedivided into the pyrolysis of coking and catalytic cracking coking. Because catalyticcracking coking formation principle and influencing factors are complex, in thispaper, numerical simulation was carried out about pyrolysis coke deposition ofhydrocarbon fuel in a single cooling channel. As you can see, we can provide datasupport for the research of coke deposition of hydrocarbon fuel in cooling channel.According to the experimental data, we calculated the high temperature gaseousfuel flow state in the cooling channel is turbulent state. In this paper, we used thediscrete particle model to simulated coke deposition. In soft–sphere approach, theoverlap between the two particles is represented as a system of springs and dashpotsin both normal and tangential directions. We considered the role of adhesion betweenthe particles and selected the Hamaker van der Waals model.Without considering the heat transfer and chemical reactions，we simulated thecoke deposition process, and the main results are summarized as the follows:When the cooling channel is rough, at the same time, the coking rate is greater,the deposition is more; the pipe is rougher, the deposition is more. Considering thefluid velocity fluctuation on the particle initial velocity, the pulse is greater, thedeposition is more.