| Diesel exhaust reforming is the process in which a catalytic reaction occurs with its reactants as diesel exhaust gas, diesel steam and water vapor and its products as H2 and CO, in conditions of high temperature and low pressure. Recycle the reformed gas, in this way, the particulate and NOx emissions reduced and the economy improved.This thesis built a model of the process of diesel exhaust gas reform, and made a sensitivity analysis of the chemical kinetics mechanism. Firstly a historical review of fuel reforming and development is provided. Future technology directions and R&D needs are also outlined.The primary reference fuel, n-heptane was blended as the model fuel of diesel, because real diesel is a complex mixture of many components. A boundary layer model is built, and the simulation compared space velocity, oxygen/carbon ratio and water/carbon ratio factors impact the reforming system.This paper introduced how to establish a chemical mechanism, and made a sensitivity analysis of the mechanisms of reforming, including the gas-phase kinetics mechanism and the surface kinetics mechanism, found main reactions whose sensitivity coefficients are large with temperature, hydrogen, n-heptane, water, oxygen and carbon monoxide. The gas-phase kinetics mechanism was predigested according to the result of the simulation. This paper also established a new model using the reduced mechanism, and compared it with the old model, there was only a little difference, besides, the compute cost was reduced too. Accordingly, the predigesting was reasonable, the predigested mechanism was able to simulate the process of diesel exhaust gas reform.A primary examination was made on the old test bench, but there was a big difference compared with the result of simulation. So this paper made an improvement of the bench on the basis of data from the simulation, mainly solving the following problems: heating of the exhaust, spraying of fuel and water and mixing of the inlet gas etc.
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