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

Direct from engine compressor, Direct from engine compressor: A Load va...

Direct from engine compressor: A Load valve is switched on from the flightdeck, power for the switch is available once the APU has achieved 95% + 3 sec. This energises the swit

Chemical engineering, i got an assignment on chemical engineering reactions...

i got an assignment on chemical engineering reactions

Classifications of moulding sands, 1. Generally moulding sands can be class...

1. Generally moulding sands can be classified as:           (a) Natural Sand           (b) Synthetic or High Silica Sand           (c) Chemically Coated Sand

Thrust indication - aircraft engine, Thrust indication: Although rpm ga...

Thrust indication: Although rpm gauges give an indication of the rotational speed of the compressor, they do have one drawback. They do not normally indicate the thrust output

Oil filter debris analysis, Oil Filter Debris Analysis Oil filters serv...

Oil Filter Debris Analysis Oil filters serve an important function within the lubrication system of a gas turbine engine in that they remove foreign particles that collect in t

The compression after impact test, This Compression After Impact (CAI) test...

This Compression After Impact (CAI) test fixture was developed by the Boeing Company. The specimen, typically, but not necessarily, a quasi-isotropic laminate, is 6" long, 4" wide,

Assignment, 1. Indicate one method for alleviating each of the following pr...

1. Indicate one method for alleviating each of the following problems associate incineration of municipal solid wastes (MSW). (a) Odors from the burning organics (b) Particulate

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