Experiment And Numerical Simulation Of Gaseous Detonation In Porous Materials

The porosity of reticulated foam has a wide range of uses,which has the advantages of high porosity and high mechanical strength.There are a variety of methods to produce porous reticulated foam such as alkali soaking method,steam hydrolysis method and heat air method.Compared with these methods,detonation method using the combustible mixed gas to produce reticulated foam has the advantages of simple process,environmental health and so on.In this thesis,to study the gaseous detonation in porous materials against the background of producing reticulated by hydrogen detonation,the experiments and numerical simulation were implemented.(1)The process of producing porous reticulated foam was simplified as detonation process in confined space,and the mixture of hydrogen and oxygen was regarded as the ideal gas.Because combustion reactions are very fast,the process of detonation in confined space were regarded as an adiabatic and isochoric process.Thermodynamic analysis of combustible gas detonation process in confined space was carried out,and the maximum pressure in detonation was calculated by reaction enthalpy method and thermodynamic energy method,The results show that reaction enthalpy method and thermodynamic energy method are consistent,which provides basis for experimental research and numerical simulation.(2)The experiments were designed according to the production process of reticulated foam,and three groups of experiments were carried out.The pressure-time curve near the wall was measured by the pressure sensor.The effects of pore size,space proportion and combustible gas mixing ratio on the detonation wave were also studied.The detonation morphology of combustible gases was analyzed according to experimental results.(3)The three-dimensional model of gaseous detonation in porous material was established.The numerical simulation was carried out with Fluent software,and using the porous medium model to characterize the effect of porous foam on the detonation wave.The effect of porous materials on the detonation wave were analyzed,and the results show that the porous material has effect on detonation wave.Numerical simulation of the detonation wave in different pore size shows that the simulation results correspond to the experimental results well.In general,with the research of theoretical calculation,experimental research and numerical simulation,the production process of reticulated foam by gaseous detonation were conducted.It has instructional significance to the production of reticulated foams by detonation.Meanwhile,the study on detonation wave in different porous materials has certain engineering application value.