Eaton Char-Lynn Motor – Variable Cycle Motor: What Performance?
The thermodynamic cycle characteristics of conventional aerospace turbine motors are fixed. An motor can only operate in one mode and has the best performance in only a limited flight range. The advanced variable cycle motor is different. It is a multi-design motor that adjusts the thermodynamic cycle parameters (such as boost ratio, turbine inlet temperature, air flow and ducting) by changing the geometry, size or position of some components. In comparison, changing the motor cycle mode (high thrust or low fuel consumption) allows the motor to work optimally in all flight situations. At the same time, variable cycle motors can operate in a variety of modes, including turbine mode, turbofan mode, and stamping mode, resulting in good performance in subsonic, transonic, supersonic, and hypersonic flight conditions.
The Eaton Char-lynn Motor states that a variable cycle motor is a gas turbine motor that achieves different thermodynamic cycles by changing the geometry, size or position of some components of the motor on one motor. Using variable cycle to change motor cycle parameters, such as boost ratio, pre-turbine temperature, air flow and bypass ratio, allows the motor to perform well under all operating conditions. In turbojet/turbofan motors, the focus of research is to change the bypass ratio, such as the reduction of the bypass ratio of the motor during climb, acceleration and supersonic flight, close to the performance of the turbojet motor to increase the thrust; When flying at sound speed, increase the bypass ratio and reduce the fuel consumption rate and noise with the turbofan motor state. In the case of turboshaft motors, the focus is on the adjustable area turbine to change the motor air flow and reduce the fuel consumption at part of the power.