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

Propeller shafts, PROPELLER SHAFTS Most modern engines, both reciprocat...

PROPELLER SHAFTS Most modern engines, both reciprocating and turbine, have flanged propeller shafts. Some of these flanges have integral internally threaded bushings that fit

Exhaust section inspection of aircraft, Exhaust Section Inspection. Ins...

Exhaust Section Inspection. Inspection of the exhaust section of the engine can be done visually using an appropriate light source. The exhaust cone and jet pipe are examined

Switching transistors, SWITCHING TRANSISTORS When a transistor is to be...

SWITCHING TRANSISTORS When a transistor is to be used as a switching device, it operates either as an open circuit (i.e. in the cut-off region) or as a short circuit (i.e. in t

Memory card functiOn, How does small memory card can read all photos and vi...

How does small memory card can read all photos and videos and saves by using what?

Linear state space equations, Linear state space equations Linear state...

Linear state space equations Linear state space equations consist of a (difierential) state equation? x = Ax + Bu and an (algebraic) output equation y = Cx + Du whe

Means of escape, Means of escape: The means of escape can start at any...

Means of escape: The means of escape can start at any point inside a building where there may be people.      The means of escape end when 'ultimate safety' is attained out

Flight dynamics - introduction, In the Aircraft Performance course, the air...

In the Aircraft Performance course, the aircraft was assumed to be in a steady-state (e.g. steady  cruise, climb, turn, glide), with the forces and moments balanced. The subject of

Edc, Combination clipper

Combination clipper

Fuel control in aircraft engine, Fuel control in Aircraft Engine: ...

Fuel control in Aircraft Engine: The basic fuel system is comprised of a fuel pump that receives low-pressure fuel from the aircraft fuel tank via a low pressure fuel valv

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