Research On Fire Stability Of Straight Jet And Relevant Combustor Design Method

With the development of aero technology, micro turbine engine and small gas turbine engine areapplied more and more widely. Combustor, as one of the key engine components, its design levelmust be improved. The improvement of design level depends on understanding the inner flow andcombustion phenomenon in combustion chamber deeply and the aid of advanced design tools.Therefore, the paper takes a research on fire steady of straight jet and relevant combustor designmethod for micro and small combustor. The research includes:Analysis the fire steady conditions qualitatively in theory and fire steady mechanism throughsimulations and visual experiments. The results indicate recirculation zone as a result of straight jet isthe key of fire steady, it’s a high temperature zone to ignite the fuel and air mixture from vaporizer atthe jet edge and form the fire front, the fire front move towards the core of recirculation zone; Thetemperature of liner dome is low at the exit of vaporizer and high at the center of recirculation zone;Build fire steady analysis model for micro and small combustor.Build a combustor preliminary design system in which design experience parameters,one-dimensional numerical computation and parametric combustor CAD model are studied. Thedesign experience formula module uses existing design experience and some other experience valuesin micro combustor through experiments, the experiments get that with the outer passage flow rateproportion increase, combustion efficiency increases, and combustor outlet temperature distributionOTDF raises and then drops, the percentage of vaporizer air flow rate4.5%is best. One-dimensionalnumerical computation module makes use of network based on pressure correction method, compile acomputation code. Parametric combustor CAD model module employs UG/GRIP to create athree-dimension model.Design the combustor MTE-170with this system, three cases satisfy the demands under theguidance of simulations, the combustion efficiency exceeds96%, the total pressure recover coefficientexceeds95%.Compare with combustor A, combustor B is better in performance. Design a new combustorbased on the size of combustor A, the total pressure recover coefficient of new combustor improves to95.4%from94.2%.