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

Problem, the royal canadian hillies plan to locate a brandy carryout in the...

the royal canadian hillies plan to locate a brandy carryout in the Yukan.A number of saint Bernard dogs ,trained by sergeant preston ,will be used to rescue lost tourists looking f

Mode iii interlaminar fracture toughness , Mode III Interlaminar Fracture T...

Mode III Interlaminar Fracture Toughness  The Mode III interlaminar fracture toughness of a composite can be measured using the split cantilever beam (SCB) geometry. Here, a c

Engine controls - aircraft engine, Engine controls: Engine controls are...

Engine controls: Engine controls are very similar to flying controls, and the same types of equipment are used, such as rods, bellcranks and cables. Most control systems use ei

Embossing and coining, Embossing is a forming operation used to create inde...

Embossing is a forming operation used to create indentation in the sheet, such as raised (indented) lettering or strengthening rips, as shown in fig. Some stretching and thinning o

Heisenberg''s uncertainty principle , According to this it is impossible to...

According to this it is impossible to specify precisely and simultaneously two physical quantities those are canonically conjugate to each other and the product of the uncertainty

Class number arrangement - library management, Class Number Arrangement   ...

Class Number Arrangement   Unlike the Cities Numbers of Dewey Decimal Classification the Colon Class Numbers have not only Arabic Numerals but also capital letters of the Roman

Resolving power and rayleigh criterion of resolution, Q. Explain Rayleigh c...

Q. Explain Rayleigh criterion of resolution. What is meant by resolving power of grating? Ans.   Resolving Power (i)  Meaning of Resolution : The resolving power of

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