Questions tagged [engine-design]
Questions about the process and principles used when designing aircraft engines. Use "jet-engine" and "piston-engine" tags to specify a certain type of engine.
276 questions
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How is the compressor shaft (inner shaft) driving the AGB mounted on top of the engine if the Exterior shaft is the Turbine output shaft?
In the T700-GE-401C/D turboshaft used in Blackhawks and MH60s, the output shaft is coming off the front of the engine (inlet) and it connects to the input module.
But the AGB (auxiliary gear box) is ...
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What powers the engine-driven alternator when turning the engines on in this turboshaft?
In the t700-GE-401c/d I get that the engine-driven Alternator is put in place to power the igniters, EDECU, and Ng readings. But how is the alternator providing electrical power for the igniters on ...
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Where is the Ng sensor located on the T700 turboshaft engine
In the T700-GE-401C/D used in Blackhawks and MH60s, where exactly is Ng sensor in this cross section picture?
(I would also appreciate any better cross-section or description.)
- 531
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T700 GE 401 c/d questions, thermocouples, Ng Np sensors, alternator [closed]
Questions about the front drive turboshaft engine T700-GE-401C/D
Where exactly are the thermocouples, Ng and Np sensors in the cross section picture below? if you have a better cross section or ...
- 531
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Civilian airplanes with inside fuselage jet engines
Like the Stratos 714 inside fuselage engine design, are there any other civilian airplanes examples alike?
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What are the differences between a big jet engine and a small jet engine?
Are there any differences in the number of components of a small jet engine like in the Cirrus Vision Jet (Williams International FJ33 engine) VS a big jet engine like in a Airbus 320(CFM56)?
Is one ...
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What is the role of guide vanes in ducted fans?
I have seen that ducted fans have stator vanes (guide vanes) behind them. What is the purpose of such vanes? Can't ducted fans be designed to operate without guide vanes to save cost and weight?
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Nomenclature: turbofan engine core
I am regularly seeing two interpretations of what an "engine core" is.
The most common use I have noticed across the web is to call it all internal modules except the fan. However, in some ...
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Why are compressor blades arranged on a "drum" and turbine blades are arranged on "discs"?
If you look at a cross-section of an engine, generally you will see the shaft in the compressor section 'flares' out to form a 'drum' type structure, while aft in the turbine section, the blades are ...
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What is the OAT limit for a flat rated jet engine?
Recently I was reading (mainly CFM presentations) about flat rated engines and EGT margin. OAT limit (OATL) was mentioned a few times.
OATL is not explained, only a formula and info that with engine ...
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How much of the air going into an engine combustor is typically fed as primary air?
I've been trying to get Google results for way too long;I know that most of the air is fed near the beginning as primary air, some is fed into the combustion later as intermediate air and the rest is ...
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Could a jet engine generate electricity for a propellor?
The fundamental rule for engine efficiency is higher bypass ratio is better since moving more air slower requires less energy for the same momentum. As such, if you could design an engine that ...
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Jet-B a viable fuel for spark ignition piston aircraft?
I've seen a video on YouTube where someone was testing various fuels in a lawnmower just to see if they'd keep it running. Like most piston engine aircraft this lawnmower is a gasoline engine with a ...
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How does the engine determine what full climb thrust is?
I fly the A350 and when full climb thrust is selected, I have noticed that the thrust target can vary. The A350 uses % THR as the primary parameter and I have noticed that sometimes with full climb ...
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Why do Airbus engines seemingly spool up faster than Boeing?
When looking at the GP7000 and Trent XWB, their spool up times are incredibly fast. Compare this to the GE90 on the 777 which takes several seconds longer, why would this be the case? Though yes, the ...
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