Cold Section ❄️ Flashcards
What does the cold section consist of
Inlet duct
Compressor
Diffuser
What does the inlet duct do
Slows air to subsonic speed
Converts kinetic to pressure energy
Smoothes air
Divergent shape
Another name for single entrance duct is
Pitot duct
Methods of FOD prevention
shrouded intakes
Vortex separator units
What is the compressor used for
Compresses air for combustion
Cooling other components from its bleed air
Pneumatic components
Cabin and hydraulic system pressurisation
Inlet anti icing
Two types of compressors
Centrifugal
Axial flow
In a turboprop and turbo shaft, both centrifugal and axial flow compressors are often used. In which order are they placed
Axial first then centrifugal (alphabetical order)
What is compression ratio affected by and what does a low compression ratio mean
Compressors type
Number of compressor stages
Means less fuel usage
Axial flow compressor ratio
1.2:1
Centrifugal compression ratio
7:1
Parts of a centrifugal compressor
Impeller
Diffuser
Manifold
One stage of a centrifugal compressor
Impeller - diffuser - manifold combination
In a centrifugal compressors what does an impeller do
Diverges air from the impeller eye via vanes forming divergent passages
What does a diffuser do in a centrifugal compressor
Converts kinetic to pressure energy, also has divergent passages further slowing air and increasing pressure
In a centrifugal compressor what does the manifold do
Straightens the compressed air and sends it to the next compressor stage or combustor
