NUMERICAL SIMULATION OF THE FORMATION OF NANOPARTICLES IN AN IMPINGING TWIN-JET  

作　　者：YIN Zhao-qin LIN Jian-zhong 

机构地区：[1]Department of Mechanics, State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, Hangzhou 310027, China [2]China Jiliang University, Hangzhou 310018, China

出　　处：《Journal of Hydrodynamics》2007年第5期533-541,共9页水动力学研究与进展B辑（英文版）

基　　金：supported by the Ministry of Science and Technology of China(Grant No.2005CCA06900)

摘　　要：The Large Eddy Simulation （LES） method has been used to solve the fluid momentum equations coupled with a convection,liffusion equation to study the formation of pollutant nanoparticles in a vehicular exhaust with impinging twin-jet. The functions of the space （S） between the two jets and the distance （H） from the exit of nozzle to the impingement plane are evaluated according to the distributions of pollutant nanoparticles. The results show that the nucleation produces a large number of nanoparticles, and gas-to-nanoparticle conversion mostly takes place in the interface region of the two jets, the circumambience of the jets, and region near the plane. The maximal particle size and maximal number concentration produced by both nucleation and coagulation appear around the region of free jet and the region near the plane, respectively. The significant differences for various spaces between the two jets are the number concentration and size distributions in the interface region of the two jets. For the case with larger space, more nanoparticles are produced by nucleation and coagulation The more the distance from the exit of nozzle to the impingement plane, the lower is the fewer the particles distribute distance from nozzle to plane is nanoparticle formation. the number concentration and near the plane. Increasing the beneficial to the reduction ofThe Large Eddy Simulation （LES） method has been used to solve the fluid momentum equations coupled with a convection,liffusion equation to study the formation of pollutant nanoparticles in a vehicular exhaust with impinging twin-jet. The functions of the space （S） between the two jets and the distance （H） from the exit of nozzle to the impingement plane are evaluated according to the distributions of pollutant nanoparticles. The results show that the nucleation produces a large number of nanoparticles, and gas-to-nanoparticle conversion mostly takes place in the interface region of the two jets, the circumambience of the jets, and region near the plane. The maximal particle size and maximal number concentration produced by both nucleation and coagulation appear around the region of free jet and the region near the plane, respectively. The significant differences for various spaces between the two jets are the number concentration and size distributions in the interface region of the two jets. For the case with larger space, more nanoparticles are produced by nucleation and coagulation The more the distance from the exit of nozzle to the impingement plane, the lower is the fewer the particles distribute distance from nozzle to plane is nanoparticle formation. the number concentration and near the plane. Increasing the beneficial to the reduction of

关 键 词：pollutant nanoparticles vehicular exhaust impinging twin-jet nucleation COAGULATION simulation 

分 类 号：X52[环境科学与工程—环境工程]