Final answer:
The three main limiting parameters of a turbojet aircraft are the exhaust velocity of gases, the rate of fuel consumption, and the aircraft's mass. These parameters define the turbojet's performance capabilities and set the boundaries for safe and efficient operation.
Step-by-step explanation:
Limiting Parameters of a Turbojet Aircraft
When considering the performance of a turbojet aircraft, three main limiting parameters define its capabilities:
The exhaust velocity of the gases (Ve) - The higher the exhaust velocity, the greater the potential for acceleration. However, there is a practical limit to Ve, about 2.5 × 10³ m/s for non-nuclear propulsion systems, due to thermal and material constraints.
The rate of fuel consumption (Am/At) - This rate determines the thrust produced by the jet engines. The faster the fuel is burned, the higher the thrust and subsequent acceleration of the aircraft. However, there are engineering and efficiency limits to how quickly fuel can be consumed without causing engine damage or reducing efficiency.
The aircraft's mass (m) - Generally, the lighter the aircraft, the greater its acceleration, given the same amount of thrust. The mass of the aircraft decreases during flight as fuel is burned, increasing acceleration. Construction materials and design influence the initial mass and therefore, limit the aircraft's performance.
These parameters are intrinsic to the understanding of turbojet aircraft performance and determine the bounds within which these machines can operate safely and efficiently.