目录

  • 1 Lesson 1
    • 1.1 Ch1 Basic mechanics
  • 2 Lesson 2
    • 2.1 Ch2 Working cycle and airflow
  • 3 Lesson 3
    • 3.1 Ch20 Thrust distribution
  • 4 Lesson4
    • 4.1 Ch21 Performance
  • 5 Lesson5
    • 5.1 Ch3 Compressors
  • 6 Lesson6
    • 6.1 Ch13 Ice protection
    • 6.2 Ch14 Fire protection
  • 7 Lesson7
    • 7.1 Ch19 Noise suppression
  • 8 Lesson8
    • 8.1 Ch5 Turbines
    • 8.2 Ch9 Internal air system
  • 9 Lesson9
    • 9.1 Ch12 Controls and instrumentation
    • 9.2 Ch22 Manufacture
  • 10 Lesson10
    • 10.1 Ch4 Combustion chambers
    • 10.2 Ch11 Starting and ignition
  • 11 Lesson11
    • 11.1 Ch16 Afterburning
    • 11.2 Ch17 Water injection
  • 12 Lesson12
    • 12.1 Ch6 Exhaust system
    • 12.2 Ch15 Thrust reversal
  • 13 Lesson13
    • 13.1 Ch18 Vertical/Short take-off and landing
  • 14 Lesson14
    • 14.1 Ch8 Lubrication
    • 14.2 Ch10 Fuel system
  • 15 Lesson15
    • 15.1 Ch7 Accessory drives
    • 15.2 Ch23 Power plant installation
  • 16 Lesson16
    • 16.1 Ch24 Maintenance
    • 16.2 Ch25 Overhaul
Ch17 Water injection

New words

        Methanol甲醇

        Coolant冷却液

        Tank 箱、槽、罐

        Microswitch微动开关

Sentence

        1. Themaximum power output of a gas turbine engine depends to a large extent upon thedensity or weight of the airflow passing through the engine. There is,therefore, a reduction in thrust or shaft horsepower as the atmosphericpressure decreases with altitude, and/or the ambient air temperature increases.Under these conditions, the power output can be restored or, in some instances,boosted for take-off by cooling the airflow with water or water/methanolmixture (coolant). When methanol is added to the water it gives anti-freezingproperties and also provides an additional source of fuel. A typical turbo-jetengine thrust restoration curve is shown in fig. 17-1 and a turbo-propellerengine power restoration and boost curve is shown in fig. 17-2.

        4. Theinjection of coolant into the combustion chamber inlet increases the mass flowthrough the turbine, relative to that through the compressor. The pressure andtemperature drop across the turbine is thus reduced, and this results in anincreased jet pipe pressure, which in turn gives additional thrust. Theconsequent reduction in turbine inlet temperature, due to water injection,enables the fuel system to schedule an increase of fuel flow to a value thatgives an increase in the maximum rotational speed of the engine, thus providingfurther additional thrust. Where methanol is used with the water, the turbineinlet temperature is restored, or partially restored, by the burning of themethanol in the combustion chamber.


全文并回答以下问题:

       Listthe two water injection methods.

       Whatis the working principle of combustion chamber injection?