Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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.
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
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:
Fire
May cause a warning horn in the u/c bay to sound
Generator Drive Low Oil Pressure or High Oil Temperature
State Vectors In engineering - particularly control engineering - most systems are represented by a state vector. - The state vector contains all of the relevant qua
Electronics Engineering Assignment# Solve problems using DC electrical principles 1.3 A 220 F capacitor is required to store 11mJ of energy. What voltage needs to appear
Re-Heat Nozzles : If re-heat was fitted to an engine with a standard sized fixed area propelling nozzle, the expansion of gases caused by the use of re-heat would increase the
Question : What is the ISM band and what is particular about this frequency band? Name two wireless technologies that make use of the ISM frequency band. a) Explain the foll
i want to do aeronautics engg. but my height is only five feet . so can i go in aeronautics
List the advantages of cold working over hot working?
the real risk free rate of interest is 3 percent. Inflation is expected to be 3 percent for 2 years. What is nominal rate of interest for the 2 years bond?
Atlas Inc. is planning to invest in a 4-year project which has the same risk as the firm’s existing assets and operations. The project requires a $150,000 initial investment and is
how to find points on Ts diagram?
Exhaust Jet Mixing: Figure shows that the noise from the exhaust jet is the main contributor to the total noise generated by a low by-pass ratio turbo-fan. For a turbo-jet the
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd