If you don't get a vacuum in the manifold of a normally aspirated diesel what sucks the air in? Do i take it you have never worked on a diesel fitted with a throttle valve then?.
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If you don't get a vacuum in the manifold of a normally aspirated diesel what sucks the air in? Do i take it you have never worked on a diesel fitted with a throttle valve then?.
Diesel Do
Well-Known Member
All diesel engines can be considered to be lean burning with respect to the total volume, however the fuel and air is not well mixed before the combustion. Most of the combustion occurs in rich zones around small droplets of fuel. Locally rich combustion like this is a source of NOx and particles.
Diesel Do
Well-Known Member
As you know, an engine doesn't suck air in, it is pushed in under atmospheric pressure! this is because of a depression in the cylinder! There is no butterfly to generate high levels of vacuum!!!
You going to tell me a diesel has the same vacuum at idle as a petrol engine?
Thought we were talking spare air and rudolf diesels principals!
There has to be a vacuum or depression formed within the engine/manifold for the air to be pushed in. In your previous post you described almost exactly what i described about twenty five posts ago. I really don't think you can be paying attention. You are just going around in circles. Thought Rudolf just pulled the sledge with the help of his mates. Anyway keep Googling i don't need to.
Datatek
Well-Known Member
Indeed until relatively recently combustion was initiated in a pre-combustion chamber, think Ricardo Comet V
Yeah i can live with that. What about this dump valve you want to fit?
Indeed until relatively recently combustion was initiated in a pre-combustion chamber, think Ricardo Comet V
That was the old anti knock chamber. Modern doozels that inject at far higher pressure don't really need those. Because the burn is much better.
Diesel Do
Well-Known Member
You never answered about volumetric efficiency which explains the spare air principle. You're just picking up on any thing to try to make your dying argument good. Even on basic diesel principle you're saying grass is blue! I'm talking very basics at the moment to attempt to differentiate between the otto cycle and the Diesel cycle. One has huge vacuum cos of the butterfly the other is an atmosphere!
Will that do you? Or am I to stupid a mechanic? Did you know rudolf diesel by the way? Did he impart this great knowledge on you? He invented it you didn't, if you can't or won't have a technical discussion and listen to others points on subjects it's a sad place to be. I still accept as a mechanic I'm learning all the time but apparently you know everything. I'm afraid on this occasion you're missing some of the finer points and will not accept it. I normally agree with you on your posts but on this occasion I'm afraid I don't. The problem seems to be you don't listen to reasoned arguments and shoot everyone down in flames. Yes they agreed with me. I respect their opinions. Like I normally do yours. Just not on this occasion but I get the impression you only ultimately like to read your own posts!
I'm happy with what I know on this subject! And if there is a new development someone brings to the table I'll listen, not tell them they're talking ****.
It's been fun
W
Diesel Do
Well-Known Member
Diesel Do
Well-Known Member
It's the facility for pre injection that made them move back to direct injection!!
but you know that!
Diesel Do
Well-Known Member
You can live with that? Well it's cos there's always excess air!
Diesel Do
Well-Known Member
Like the ILT! Or an old fashioned engine! I've worked on engines that use them purely to turn them off! But that does not make it regulate air!
There are some, like the old Transit that had linked throttle valves. They regulated air. But it's a free for all normally as far as induction is concerned. Just think if you got an old Transit and fitted a turbo you could have a dump valve.
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Are you googling at the minute?
No have been and made a brew, as i said i don't need to Goggle. I may forget things now and again though.
Diesel Do
Well-Known Member
There are some, like the old Transit that had linked throttle valves. They regulated air. But it's a free for all normally as far as induction is concerned. Just think if you got an old Transit and fitted a turbo you could have a dump valve.
Ah but as you know you don't need a butterfly for a dump valve! Just a micro switch and a pierburg valve! Thought a turbo whistler for your exhaust would be more up your street
Diesel Do
Well-Known Member
Here's one for you! Google air fuel ratio of a diesel at idle?
Well it will be pretty massive.
Diesel Do
Well-Known Member
:5blurk5: Anyone wanna share??
They can exceed 145 to 1! Possibly due to the excess air? Maybe
