Contents
8 Pneumatic Actuators, Driving Elements, and Accessories . . . . . . . .
1
8.1 Pneumatic Cylinder and Hydraulic Cylinder . . . . . . . . . . . . . . .
1
8.1.1 Classification of Pneumatic Cylinder and Hydraulic
Cylinder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
8.1.2 Natural Frequency of Pneumatic Cylinder . . . . . . . . . .
2
8.1.3 Natural Frequency of Hydraulic Cylinder . . . . . . . . . . .
8
8.1.4 Comparison of Pneumatic Cylinder System
and Hydraulic Cylinder System . . . . . . . . . . . . . . . . . . 11
8.1.5 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.2 Structure and Characteristics of Actuators . . . . . . . . . . . . . . . . 13
8.2.1 Pneumatic Cylinder . . . . . . . . . . . . . . . . . . . . . . . . . . 13
8.2.2 Pneumatic Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
8.3 Aircraft Hydraulic Accumulator and Cylinder in Extreme
Temperature Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
8.3.1 Extreme Temperature Environment . . . . . . . . . . . . . . . 40
8.3.2 Van der Waals Equation for Real Gases . . . . . . . . . . . 41
8.3.3 Inflation Mass of High-Pressure Gas Cylinders . . . . . . 42
8.3.4 Gas Pressure Service Characteristics of High-Pressure
Cylinders and Cavities . . . . . . . . . . . . . . . . . . . . . . . . 43
8.3.5 Service Characteristics of Accumulator . . . . . . . . . . . . 46
8.3.6 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
9 High-Temperature and High-Speed Gas Turbine Pump
Electro-Hydraulic Energy System for Aircraft . . . . . . . . . . . . . . . . 51
9.1 Electro-Hydraulic Servo Control Technology of Aircraft
Gas Turbine Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.1.1 Overview of Electro-Hydraulic Control
Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.1.2 Elastic O-Ring Sealing Technology . . . . . . . . . . . . . . . 58
xi
8 Pneumatic Actuators, Driving Elements, and Accessories . . . . . . . .
1
8.1 Pneumatic Cylinder and Hydraulic Cylinder . . . . . . . . . . . . . . .
1
8.1.1 Classification of Pneumatic Cylinder and Hydraulic
Cylinder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
8.1.2 Natural Frequency of Pneumatic Cylinder . . . . . . . . . .
2
8.1.3 Natural Frequency of Hydraulic Cylinder . . . . . . . . . . .
8
8.1.4 Comparison of Pneumatic Cylinder System
and Hydraulic Cylinder System . . . . . . . . . . . . . . . . . . 11
8.1.5 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.2 Structure and Characteristics of Actuators . . . . . . . . . . . . . . . . 13
8.2.1 Pneumatic Cylinder . . . . . . . . . . . . . . . . . . . . . . . . . . 13
8.2.2 Pneumatic Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
8.3 Aircraft Hydraulic Accumulator and Cylinder in Extreme
Temperature Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
8.3.1 Extreme Temperature Environment . . . . . . . . . . . . . . . 40
8.3.2 Van der Waals Equation for Real Gases . . . . . . . . . . . 41
8.3.3 Inflation Mass of High-Pressure Gas Cylinders . . . . . . 42
8.3.4 Gas Pressure Service Characteristics of High-Pressure
Cylinders and Cavities . . . . . . . . . . . . . . . . . . . . . . . . 43
8.3.5 Service Characteristics of Accumulator . . . . . . . . . . . . 46
8.3.6 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
9 High-Temperature and High-Speed Gas Turbine Pump
Electro-Hydraulic Energy System for Aircraft . . . . . . . . . . . . . . . . 51
9.1 Electro-Hydraulic Servo Control Technology of Aircraft
Gas Turbine Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.1.1 Overview of Electro-Hydraulic Control
Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.1.2 Elastic O-Ring Sealing Technology . . . . . . . . . . . . . . . 58
xi