Airflow control system principles-aircraft engine, Other Engineering

Airflow control system principles:

For any given engine there is only one set of conditions, mass flow, pressure ratio and rpm, at which all the compressor components are operating at their optimum effect. Compressors are designed to be most efficient in the higher rpm range of operation. The point at which the compressor reaches its maximum efficiency is known as the DESIGN POINT. Under design conditions the compressor produces a given compression ratio (ie.Volume 2/Volume 1) and the axial velocity (average velocity) of the gas remains approximately constant from the front to the rear of the compressor.

The Angle of Attack of the airflow to the compressor aerofoil blades will be at its optimum. This is the design condition and the compressor is operating at its optimum performance. Although compression ratio varies with rpm it is not proportional to rpm. This fact emerges due to the fixed blade angles, which can only be correct at the design point. To illustrate this fact, refer to the diagram showing rpm and compression ratio. Consider a compressor running at 8,000 rpm and its compression ratio is 10:1. Let us say that the volume of air entering the compressor is 100cm3. The volume of the air passing through the fixed outlet annulus of the compressor will be 10cm3.

710_airflow control system principles.png

Compressor R.P.M = 8,000 Compressor R.P.M. = 4,000
Compression Ratio = 10:1 Compression Ration = 4:1
Volume of gas (V1) = 100cm3 Volume of gas (V1) = 50cm3
Volume of gas (V2) = 10cm3 Volume of gas (V2) = 12.5cm3

Posted Date: 9/11/2012 8:52:30 AM | Location : United States







Related Discussions:- Airflow control system principles-aircraft engine, Assignment Help, Ask Question on Airflow control system principles-aircraft engine, Get Answer, Expert's Help, Airflow control system principles-aircraft engine Discussions

Write discussion on Airflow control system principles-aircraft engine
Your posts are moderated
Related Questions
Cash Flow Diagrams We will use a cash flow approach to analyze the flow of money through out a planning horizon. A cash flow occurs when money actually change hands. We will u

compute IDFT using DIT and DFT X(K)={20,-5.828-j2.414,0,-0.172-j0.412,0,-0.172+j0.414,0,-5.828+j2.414}

Permeability of Moulding Sand  is the property of the sand, which permits the gases and steam to escape through the sand mould. For this purpose, the sand must be porous. Permeabil

routing sheet for rh shaft

What isplant

Real time processing is suitable when it is necesssary to have the latest information in the following types of business operations

why shift variant system causes artifacts

Matrices for risk analysis: NFPA 551 describes a technique of using matrices for risk analysis.  Such matrices are quite commonly used in the UK for assessing risk but, fortun

why we use h for bjt

Extended input facilities Another instance where multiple inputs to a single gate operation can occur is with certain types of gate elements that have an 'EXTENDED INPUT' facil