拉瓦尔喷管计算模型的改进及其整机仿真验证

Improvement of Laval nozzle calculation model and simulative verification in aero-engine performance calculation

根据拉瓦尔喷管的典型工作状态,建立了零维拉瓦尔喷管气体动力学模型,并将其集成到发动机整机部件级模型中,开展了发动机整机加速动态仿真.仿真结果表明:①随着喷口面积的不断收小,发动机低压转速加速曲线存在一段"先降后升"区域,这与实际试车结果吻合;②贴口正激波被推出管外的瞬间,出口马赫数从亚声速突变至超声速,但喷管出口流量、发动机推力变化连续,未见突变现象.

By analyzing typical operating regimes of Laval nozzle,a zero-dimensional pneumatic model was built to evaluate the influence of Laval nozzle on the performance of aero-engine.The Laval nozzle model was integrated into a whole aero-engine component-level model.Numerical simulations were performed to study transient performance of aero-engine when nozzle throat and outlet areas decreased during accelerating process from idle to middle state.Results show that low pressure rotor speed decreases during some spe...