Apu engine, Other Engineering

Assignment Help:

APU Engine

APU engines usually consist of a centrifugal compressor and a radial turbine however, axial compressors and turbines may be added or used in their own right. Centrifugal compressors are used because of their high compression and small size and when combined with a radial type turbine make the APU very compact. These components are also very robust and require less maintenance than axial flow components. Use is also made of reverse flow combustion chambers that again makes the overall size smaller.

220_APU engine.png

In most cases there is a design compromise made between the ideal APU for an aircraft i.e. its ability to provide air and electricity throughout the operational envelope of the aircraft, and it weight and size. It is usual therefore to find that air and electricity are limited to various altitudes dependant upon the parameter required.

APU systems are very basic and the APU will shut down if a problem is sensed. Most APU's will shut down for the following faults:

Fault

Comment

Low Oil Pressure

 

Engine Overspeed

110% Honeywell 108% Sundstrand

High EGT

849°C Honeywell

Loss of Speed Signal

Electronically monitored APU's need this signal to control the APU.

Los of EGT Signal

Electronically monitored APU's need this signal to control the APU.

Low Speed

Some APU's shutdown if they drop below 90%.

(Some will try and relight at 95%)

Electronic Unit Failure

Loss of Control

The APU may also shut down on the ground (not in flight) for the following faults:

Fault

Comment

 

Fire

May cause a warning horn in the u/c bay to sound

Generator Drive Low Oil Pressure or High Oil Temperature

 

 


Related Discussions:- Apu engine

Sprinkler system - fire protection engineering, Sprinkler system - fire pro...

Sprinkler system - fire protection engineering Sprinkler systems may be installed in a building to achieve a number of different objectives.  Very often the primary reason for

. CFD, HOW TO MAKE ROTATING FRAME

HOW TO MAKE ROTATING FRAME

Capital budgeting, explain the objective of capital budgeting

explain the objective of capital budgeting

Dsp, h(t) is an analog IIR filter, with the poles lambda_1 = -1, lambda_2 =...

h(t) is an analog IIR filter, with the poles lambda_1 = -1, lambda_2 = -1+i, lambda_3 = -1-i and no zeros. let h[n] be a digital IIR filter with poles which defined by e^lambda_i a

Double acting feathering system, Double acting feathering system: To pr...

Double acting feathering system: To prevent excessive drag in the event of a propeller on engine failure, the double acting propeller as with the single acting propeller requir

Statics, Create resolving questions on comments of couples

Create resolving questions on comments of couples

Dynamic model of pitching motion , It is instructive to investigate the pit...

It is instructive to investigate the pitching motion caused by a disturbance from trim due to a control surface deflection. We shall assume that the velocity remains constant, and

Steamtables, How to draw diagrams for Rankine cycle

How to draw diagrams for Rankine cycle

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd