一种通用涡轴发动机起动过程建模方法研究

A Research on Start-Up Modeling for Turbo Shaft Engines

关键词:  涡轴发动机  起动建模  部件级模型  级累叠法

Key words:  Turbo shaft engine  Startup modeling  Component-level model  Stage-stacking method

摘要:

涡轴发动机可靠、快速的起动过程是进入驱动旋翼飞行器安全工作的前提，高置信度的发动机起动过程模型不仅可以对起动过程进行分析与优化控制，而且减少了代价昂贵的发动机台架试车次数。本文针对起动过程复杂非线性特性的建模难题，提出一种通用的建模方法:即基于级累叠方法，根据进口条件计算各级气体流动参数来获得压气机低转速特性数据，同时根据相似原理外推出燃气涡轮、自由涡轮低转速部件特性，并将冷转动模型和部件级模型相结合。最后，建立了涡轴发动机起动模型，进行了地面状态起动过程的数字仿真，并与试车数据进行对比，最大误差小于10%，结果表明所建立的模型能准确模拟涡轴发动机的起动过程。

Abstract:

A reliable and quick starting process of turbo shaft engines is the premise of safety work into the drive of rotor aircraft，a starting process model with high fidelity can help to analyze and optimize the starting process of engines and the cost of rig tests will be reduced. To solve complex nonlinear characteristics of modeling problems in the starting process，a general modeling method named stage-stacking method is put forward，according to the inlet conditions，to obtain the low-speed characteristics data of compressor，the flow parameters of all stages are calculated .On the basis of similarity principle，the low-speed characteristics data of gas turbine and free turbine is calculated. The startup model proposed is a combined calculation for component level cooperated-working and cold working before ignition. Finally a startup model for some turbo-shaft engine is established，and the digital simulation under the standard ground state is conducted. Compared with the rig test data，the maximum error is less than 10%. The results show that the established model can be applied to simulate the starting process for the turbo shaft engine.