| As one of the three major components of a gas turbine,the performance of the combustion chamber directly determines the performance of the gas turbine.In recent years,with the continuous development of gas turbines in the direction of high temperature rise,high power and low emissions,the design method based on prototype improvement faces a series of difficulties and challenges.Therefore,it is urgent to develop an independent combustor design method to meet the design requirements of the matching and service of the gas turbine.At the same time,the nozzle is an important part of combustor,and its atomization performance directly affects the mixing of oil and gas and combustion organization of the combustor,but its design method and preformence study are often independent of the combustor design method.In response to the above problems,the following study was carried out:(1)Carry out research on the design method and parametric multi-dimensional modeling of the gas turbine combustor,analyze the correlation between the three-dimensional modeling of the combustor and the zero-dimensional design,and based on the given design conditions and constraints,the structural size of the combustor is designed by the pressure loss method.Based on the research on the zero-dimensional design of the combustion chamber,the UG modeling software platform is used to realize the multi-dimensional parametric modeling of the combustion chamber,which is beneficial to further improve the design efficiency of the combustion chamber.The results show that the pressure loss coefficient of the combustion chamber is 3.78%,which is less than 5% of the design value,and the performance of the combustion chamber meets the design requirements.(2)Based on the design method of the fuel atomizing nozzle and the design requirements of the combustion chamber for the nozzle,the performance of the fuel atomizing nozzle is studied by combining numerical simulation and experiment.The nozzle structure is designed by the empirical coefficient method,and the influence of the inlet pressure on the atomization characteristics of the nozzle is studied based on the existing atomization test bench.Finally,the numerical simulation model of the nozzle is verified according to the test results,and numerical simulation is used to analyze the influence of inlet pressure,outlet length,and outlet diameter on nozzle atomization characteristics.The results show that with the increase of inlet pressure and outlet length,the atomization cone angle increases;with the increase of outlet diameter,the atomization cone angle first decreases and then increases.(3)Carry out research on the cold and hot state field performance of the combustion chamber.Based on the designed nozzle and combustion chamber,numerical simulation is used to study the typical structural parameters of the diffuser and the flame tube(expansion angle,sudden expansion gap,flame tube length,flow rate distribution,OTDF target value)on combustion chamber performance The results show that the optimal values of the expansion angle and the sudden expansion gap are 16° and 50 mm.Increasing the length of the flame tube and the ratio of the flow rate of the main combustion hole and the mixing hole can improve the outlet temperature distribution. |
