How Jet Engines Work — Cirrus Vision Jet Engine | Williams International FJ33-5A Fanjet Engine

hi rich pickett i'm going to talk about the williams international fj335a engine it generates 1846 pounds of thrust at sea level and weighs just a little bit over 300 pounds pretty amazing it powers the cirrus vision jet so this is going to be kind of an introduction on some of the how the how the engine works so we're talking about some components first and then we can go into more details so to give you some ideas we're going to talk about the n1 also called the low pressure system of the engine which comprises of the fan these compressors here and these turbines talk about that then we'll talk about the n2 section which is considered the high pressure system and that's the centrifugal compressor here as well as this turbine here and a few other components so as we look through here let's talk about some other things before we get going this area up here is the bypass so since this is a medium bypass engine over 50 percent of the air literally bypasses the combustion portion of that engine and shoots out around the core it does a couple things it makes it really quiet it also helps uh provide some efficiency the poppet the poppet valve here for the bleed air is here we'll talk a little bit about that and then we have it here is where a combustion chamber is so this model as we get going i'll show you it's not exactly perfect because what happens is you notice if i turn the fan everything moves in real life this n1 or low pressure section or component of the engine is actually on an inner shaft and then the n2 or the high pressure is on an outer shaft so they rotate different uh independently so let's talk about this so all of a sudden you're a pilot you're in a plane you go through and you um on any of these jet engines but let's see in this one in particular so what happens is you turn the switch in the in the cirrus visions yet to run and then you pressure your start stop button so there's a lot of other things that go on but for our purposes let's just talk about the engine so what happens then is a starter generator which is a starter when it starts turns into a generator once engine started through this tower shaft you can barely see it in through here turns this gear here and starts the spinning of the into section so the into section again is going to be this centrifugal compressor here in this turbine and some other components so as it turns and you can see it turning through there again n1 wouldn't move at this point as it turns right when it gets to about eight percent roughly in two then what that means is the rpm we'll talk a little bit about rpm in a minute as that turns then fuel is injected into this combustion chamber as well as the igniters are one igniter is on so when the ignition is on click the click tick tick and you can hear it in the plane goes tick tick tick tick tick that means igniter is on it's like a spark plug then fuel is introduced and then once the combustion starts all right so once you've got a fire going in here what happens is the exhaust air comes through here comes through this turbine wheel here and goes to these two turbine wheels here now the air is directed through these these gray rings are actually called stators they're fixed so it helps direct the air in a particular direction so it's going to point it up in this model point it up hits this fan blade turns that as the air comes off of that fan blade then it's going to come up to this stator angle up and hit this again so these are still low pressure but they're considered the turbines low pressure turbines so now this has started to turn this has started to turn because you still have your starter turning right so until it gets to about 30 into then it starts to accelerate and then the starter actually disengages in the spark plugs and we have a continuous fire combustion in here so it's self-perpetuating so then this is turning right so we have this turning our n2 is turning this guy is turning i like to see n1 usually in this plane you usually see it at around 16 other williams engines i see them at least by 19 in two so that starts turning this is connected to here the fan remember that's that outer shaft in one section so this is turning so you've got this turning from the initial exhaust this is turning then the intake air the part that does not go across the bypass goes through these intermediate pressure compressors here so in through here we have three stages so it's called three stage compressor with again stators that help direct the flow so there comes down here hits that the stator directs it up hits the second another stator directs it up and then hits this third stage so again so now all of a sudden this thing is going faster and faster right faster and faster we're going through and as it accelerates from all this exhaust then this air here comes back through here and hits the centrifugal compressor so initially remember we are starting the engine by this just mechanical connection between the starter and the tower shaft to the n2 section but now we have that combustion gases powering the centrifugal compressor so at a certain point that starter will become disengaged because it doesn't need to be anymore as started turns into a generator now up here we talked a little bit about the bleed air the bleed air is used for various purposes in the plane right so we use it for our environmental system we use it for the boots on the vision jet we use it to heat the air around the nest all of the engine well if you have too much at idle you could have compressor stalls so there's a little valve here it's not shown here that opens to relieve some of that pressure so now what's happening is as this continues to burn and it engine accelerates right from that fire in there all this air is coming through here additional compression in here by the centrifugal compressor hits that turbine hits these turbines which can connect it to the n1 and it accelerates and gets to an idle rpm depending upon the williams engine idle rpms are in the low 50s percent for example other engines are a little bit different so here that starts running right and we have a stable start itt starts to come down everything is stable n2 is stable and one is stable and we have a good start it's pretty cool isn't it it's amazing how that works oh also before i forget this tower shaft i didn't tell you everything that's connected to down here it's connected in the accessory gearbox so not only does he have the starter generator it also has what's called a pma permanent magnet alternator and down there that is also in there's fuel pumps down there that permanent magnet alternator is what powers the fedex once the engine starts the fedex is the full authority digital engine control that controls all the stuff and keeps it stable and adjusts for outside air temperature etc altitude etc it's amazing so now this is spinning remember we talked about eight percent n2 so what the heck is eight percent well at a hundred percent the um this n2 is running at about 50 thousand rpm at a hundred percent in one this low pressure section in here is running around 20 000 rpm plus or minus uh to give you an idea so it's spinning pretty darn fast so it's amazing it goes boom that's how the williams fj 335a engine operates in a very simple interpretation thanks [Music] you

Channel: Personal Wings

Views: 279,740

Keywords: vision jet, cirrus vision jet, williams international, fj33-5a, fj33, jet engine, fanjet, turbofan, how jet engine works

Id: ReO65qjrgHQ

Length: 8min 25sec (505 seconds)

Published: Thu Apr 28 2022