Research Of Gas Dispersion And Explosion And Protective Technology In Restaurant Kitchen

Along with China's urbanization and the rapid growth of national economy,natural gas has been widely used in the cities and towns.Meanwhile,the gas explosions occurred frequently as the result of the gas leakage due to the pipeline aging and corrosion puncture,which have caused great casualties and economic losses.The gas explosions happened in the restaurant kitchens,which are open to the public and normally located in urban area,would cause more casualties.Therefore,it is very urgent to investigate the process of natural gas and dispersion.Although the researches on the gas explosions have been carried out for many years,they are mainly focused on the gas leakage and explosions in gas/oil plants.There are barely papers focused on the indoor gas dispersion and explosion.The reason and explosion load for natural gas is still unclear.And compared to TNT explosion,natural gas explosion has a longer duration and lower peak pressure.The failure of structures under TNT explosion and natural gas explosion has a big different.In this paper,the CFD software FLACS was used to investigate the gas dispersion and explosion in a typical restaurant kitchen.The blast wave propagation and the blast load on the walls were derived and studied.Parametric studies were also carried out to find out how the gas concentration effect on the peak pressure when explosion happened.Besides that,the different kinds of glasses' response under different loads were also studied.Based on the numerical results,two protective methods were put forward,firstly is about how to expand venting area to decay the explosion load;secondly,is how to strength structure member to against the explosion load.The result shows that,when the gas leakage happened,most part of the natural gas is gathered near the roof.The max pressure of different monitor points in the room is quite similar.And increasing the venting area can reduce the explosion pressure efficiently.Comparing normal glass and PVB glass,PVB glass has a better performance of blast resistance.A PVB glass with 10 mm thickness could resistant natural gas explosion effectively.