Research On The Influence Of Guide Vane Structure On The Performance Of Turbine Inter-Vane Burner

To improve the performance of gas turbine engines, more and more interests have been showed onTurbine Inter-Vane Burner (TIB). The thrust per weight ratio of the aeroengine will be increased andthe pollutant emissions will be decreased when the TIB is applied. To explore the influences of theguide vane structure over the performance of aeroengines, seven TIB configurations were developedwith different guide vane structures on the basis of present achievements. A commercialComputational Fluid Dynamics package, FLUENT, was used to numerical simulate the flow andcombustion details in the TIB. The numerical results were then used to optimize the design ofexperimental models and testing working conditions.The impacts of the run conditions exerted to the TIB were first investigated in this thesis. Theresults show:(1) the mathematical models and numerical methods could simulate the flow andcombustion in the TIB accurately.(2) The TIB could operate steadily under a wide range ofequivalence ratios (1.62-0.81). The gas temperature was increased by about650K with highcombustion efficiency and low total pressure loss.(3) As the second air flow rate increased, thecombustion efficiency enhanced and the pollutant emissions (CO, UHC) reduced. The mixing ofthe high temperature combustion gas and the main gas also could be strengthened by increasing thesecond air flow rate; as a result, the temperature distribution was improved. However, the totalpressure loss increased.(4) When the second air flow rate maintained constant, increasing theoperating pressure made the combustion more complete, as a result, the emissions (CO, UHC) andthe total pressure loss reduced and the combustion efficiency enhanced. The emission ofNOXincreased significantly, though.Numerical simulations were then conducted on the TIB configurations with different radial vanecavity (RVC) structures and the results were compared with the basis configuration. Simulationsindicated:(1) decreasing the angle of aft end face of the RVC was benefit to the design. The flowpattern could be improved effectively and the total pressure loss decreased. The temperaturedistribution was also improved.(2) When the front face of the RVC was changed backwards, the totalpressure loss increased. It was appropriate to low second air flow rate conditions.(3) Adding a RVCin the concave side, the emission ofNO Xdecreased, however, the total pressure loss increased. Itwas good for high second air flow rate conditions.(4) Cutting the guide vane in two, the combustionefficiency boosted and the temperature profiles of the passage between the guide vanes improved in the cost of larger total pressure loss.(5) Generally speaking, the performance of TIB under lowsecond air flow rate was strongly influenced by the structure of the RVC. The bigger the RVC was,the more intensive interactions there were. Consequently, the emissions (CO, UHC) decreased andthe combustion efficiency rised.Finally, the TIB with curved guide vane was numerical studied. The results indicated:(1) airflowdetached the convex side of the vane and back-flow arose in the detachment zone, as a result, the totalpressure loss soared, especially if the RVC was located in the convex side of the vane.(2) Thevelocity at the outlet was well-distributed and velocity difference was little, particularly the TIBmodel with RVC in the concave side of the guide vane.(3) Relatively complete combustion tookplace the combustion ring, so there were less high-temperature zones and the temperature wasrelatively uniform in the passage, especially under the low second air flow rate conditions.(4)Compared to the TIB whose RVC was located in the convex side of the curved guide vane, the TIBwith RVC in the opposite side performed much better in the fields of total pressure loss, pollutantemission, combustion efficiency, temperature and velocity distributions.