Research On The Explosion-proof Performance Of Coal Mine Diesel Engine’s Dry Exhaust System

With the rise of the modern mechanized develepment in coal mining, the coalmine has already started to use a lot of trackless rubber-tyred cars powered by thediesel engine.In the process of coal mining, there would generate a large amount offlammable and explosive gas in roadway, so preventing the mine gas explosion is themost important for the coal mine safety. As we all known, the exhaust gastemperature of ordinary diesel engine in the working process can be as high as600℃,so diesel engine needs to be designed for coal mine explosion-proof, especially forhigh temperature exhaust gas coming from the exhaust system. The exhaust system’sexplosion-proof design is the important part of explosion-proof diesel engine. Theexplosion-proof design is to reduce the exhaust temperature so that the exhaust gascan achieve the use of coal mine safety standard.This paper is researched onperformance of the jet dry exhaust pipe on a explosion-proof diesel engine, and thepaper research content is as follows:Firstly, in this paper a six-cylinder diesel engine is the prototype, by improvingthe original machine’s inlet and exhaust system and cooling system to meet thedemands for coal mine explosion-proof.Proposed to the explosion-proof design ofdiesel engine intake and exhaust system and cooling system. Especially for the dieselengine’s exhaust system, putting forward the jet dry exhaust pipe device for theexhaust system.Secondly, jet theory is introduced in detail, and the fluid dynamics equationwhich is used in the jet pipe. At the same time, the jet pipe’s type and ejectorperformance evaluation index has been introduced, and proposed a jet dry exhaustpipe design structure in this research.Thirdly, by using3D modeling software CATIA to establish the jet dry exhaustpipe geometry model, and by using CFD software STAR-CCM+to extract the flowcomputational domain of the exhaust pipe, generate polyhedron mesh, and setphysical models and boundary conditions. By calculating and analyzing the internalflow field of jet exhaust pipe, we can get the pressure, velocity and temperaturedistribution in the flow field, which will be used for the parameter optimization design.Finally, by changing the parameters of jet dry exhaust pipe structure of differentsize: the size of the throat, the length of the tail pipe, gas jet Angle and exhaust outletdiameter, can get the influence of various parameters on the jet pipe ejector’sperformance.And simulation and parameter optimization based on the orthogonalexperiment table than can obtain a suitable jet dry exhaust pipe for theexplosion-proof diesel engine.