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Air Intake Requirements

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Air Intake Requirements

Old 01-29-2024, 07:10 PM
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jofunk
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Default Air Intake Requirements

What is the air intake formula for a turbine? Square inch of intake required / pound of thrust.
Old 01-30-2024, 01:05 AM
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cetigershark
 
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Default turbine inlet area

Originally Posted by jofunk
What is the air intake formula for a turbine? Square inch of intake required / pound of thrust.
Hi Jofunk
Usually the turbine manufacturer recommends a minimum inlet area in his operation manual. And that is at least the turbine front area.

Regards
Chris
Old 01-30-2024, 07:09 AM
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rcmigpilot
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It would help to know what your application and proposed motor are. There isn't really a hard and fast rule for turbines like with EDFs. Turbines will suck the air they need, if there's not enough coming in they will either suck in the intake or in extreme cases suck in the fuse.
Old 01-30-2024, 02:08 PM
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jofunk
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I looked through a few turbine specs. but didn't see anything. I thought I remembered an A M T rep. say that their Mercury needed nine square inches of intake.
Old 01-31-2024, 09:25 AM
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why_fly_high
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Default Not just area

The engine needs XXX cubic feet of air at full throttle. If the plane is going 200mph, the about of inlet needs to get the required cfm is quite low. On the other hand, a thrust vectored hovering jet needs that sane CFM at 0 miles per hour so the inlet size needed is much bigger.
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Old 01-31-2024, 01:58 PM
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Helijet
 
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Based on experimentation by various engine and airframe manufacturers years ago

Inlet flow through MUST always go from small to large.
Inlet area requirement is 1.5 X the compressor area.
Allow for sufficient airflow or gapping within the fuselage to prevent doors / canopy from
closing shut / imploding.

dw
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