Combustion Chamber Simulation And Structure Optimization Of The Composite Heat Carrier Generator

As the main source of energy in today’s world,oil has a very important strategic value for country’s steady development of the economy and society.In the near future,the oil will still be the main energy source and act as the engine of human social development.As China’s major oil fields are in the late exploitation period,it has become a real problem to efficiently exploit these old fields.In addition,there are still many heavy oil fields which can not be commercially exploited because of the high cost of production and huge waste of resources.To deal with these problems,the technology of crude oil steam injection boiler has been developed,but the poor mobility of water vapor limits the application in the actual production process of the technology.The composite heat carrier generator is a new type of invention patent.It uses the knowledge of heat transfer and thermodynamics to generate large amount of high-temperature and high-pressure gas through combustion and then inject the gas into the oil layer of the oil field.This equipment greatly improves the production rate of oil field and has a strong application value.However,in practical applications,it is found that the outer wall of the combustion chamber of the equipment is prone to overheat ablation phenomenon,which causes the equipment to be damaged and can not operate effectively.In this thesis,numerical simulation technology is applied to simulate the reaction process of combustion chamber composite heat carrier generator.Optimal running parameters and structural parameters are determined by the simulation results.The research work of this thesis mainly includes the following aspects:(1)Design of the 3D model and the mesh of the composite heat carrier generator.Before dividing grid,the model of the composite heat carrier generator needs to be simplified based on the principle that the reaction process of the combustion chamber is not influenced greatly.Then the mesh of the simplified model is divided,the quality of the mesh generation is checked to make sure that the simulation results are accurate and reliable.(2)Thermal simulation of the combustion chamber of the composite heat carrier generator under the basic conditions is performed.The basic operating conditions are provided by the manufacturer in actual operations of the equipment.By thermal simulation,the temperature field,pressure field,flow velocity and the concentration of the reactant in the combustion chamber are obtained.(3)With changing some running parameters,the thermal simulation of the combustion chamber of the composite heat carrier generator is carried out.In the analysis process,the four parameters of oxygen concentration,combustion pressure,fuel type and cooling water quantity are changed.The effects of these parameters on the combustion chamber are determined by the results of thermal simulation.(4)With changing some structure features of combustion chamber of the composite heat carrier generator,the thermal simulation of the equipment is carry out.In the process of simulation analysis,by changing the injection angle of the oxidant nozzle of the combustion chamber,diameter of combustion chamber and the new oxygen enriched combustion model,the reaction process of combustion under new structure is investigated by the thermal simulation.According to the simulation results,the changing states of the combustion chamber are analyzed after changing the structure,it provides a basis for the improvement of the composite heat carrier generator model.