This research aims to propose a method to achieve the maximum altitude adaptability of turbocharged diesel engines with the optimum fuel consumption. Firstly, engine performance at different altitudes is studied by experimental method. It is found that the engine power recovery is restricted by three constraints, which are cylinder pressure, exhaust temperature and boosting pressure ratio. Following that, the influence of turbocharging system and fuel injection on the three constraints is studied via experimentally validated numerical model. A power-recovery-zone bounded by the three constraints is proposed, inside which engine power can be fully recovered. The altitude adaptability of the engine is discussed in details via this zone. Further analysis finds that the boosting pressure and the maximum pressure ratio are the key factors to the constraints. A new methodology which can achieve the maximum altitude with the optimum fuel consumption is proposed based the concept of the zone. Finally, the methodology is applied in the engine with three types of turbocharging systems to quantitatively compare their altitude adaptability. Results prove that the altitude adaptability of the engine is notably improved by adapting the proposed method, especially for the two stage turbocharging system.

本研究旨在提出一种以最优油耗实现涡轮增压柴油机最大高度适应性的方法。首先，通过实验方法研究了发动机在不同海拔高度下的性能。结果表明，发动机功率回收受到气缸压力、排气温度和增压比三个约束条件的制约。随后，通过实验验证的数值模型研究了涡轮增压系统和燃油喷射对三个约束条件的影响。提出了以三个约束为界的功率恢复区，在该区内可以完全恢复发动机功率。通过该区域详细讨论发动机的高度适应性。进一步分析发现，增压压力和最大压力比是制约的关键因素。基于区域的概念，提出了一种新的方法，可以在最佳油耗的情况下实现最大高度。最后，将该方法应用于具有三种涡轮增压系统的发动机，以定量比较它们的高度适应性。结果证明，采用所提出的方法，发动机的高度适应性得到显着提高，特别是对于两级涡轮增压系统。