Turbocharging a diesel engine?

[Jonny88]

Hi folks,

I'm looking to find out as much as I can about the turbocharging of diesel engines. Looking more at large installations for ships and things, but any theory anyone might be able to pass on would be great!

Thanks in advance.

Jonny.

[gonzo]

Do you plan on turbocharging an existing engine. It will need different pistons and rings, Valves and guides may not work, lower compression, fuel injection pump and injectors.

[Jonny88]

Not planning to do anything to anything.

Need to learn about it for a bit of undergraduate work I'm doing and thought a boating forum might be a good place to start. I already have a pretty good knowledge but is pretty difficult to come across anything half decent on the internet so thought I'd ask.

Cheers.

[Submarine Tom]

Why?

If it's general interest simply Google it but if you have any specific question then ask.

-Tom

[gonzo]

Check out manufacturer's websites. They will give you all the specifications and technical data.

[JosephT]

Turbo charging any engine will put a heavier load on the engine. You should check with the engine manufacturer or a highly experienced engine shop before considering it. If the block, pistons, rings, etc. can take this additional load then the next step is to consider what type of turbo charger to install.

Regards,

Joe

[Submarine Tom]

...and how many pounds (Newtons) of boost to use...

-Tom

P.S. Or is it kilo-pascals not Newtons...

[Easy Rider]

What are the ups and downs of running a turbo diesel at 50% load or less over extended periods? Would Would the removal of the turbo be a good option?

Easy Rider

[FAST FRED]

"Would Would the removal of the turbo be a good option?"


On many engines the block, turbo or non turbo is the same but the compression ratio is lower on the turbo engines.It might run really poorly with out the turbo.

Turboed engines may also have an intercooler of some type.

On some Perkins I have seen the turbo kept , and the rotten really expensive intercooler simply tossed.

Probably some loss of power and efficiency , but on a 8K trawler , who would miss it?

FF

[Easy Rider]

Fred,
I feel really stupid ..forgot about the compression ratio. There must be a point down at the lower end (rpm) where the boost is insufficent to bring the BMEP up the NA engine level. So it would seem a turbo engine would be actually less efficent than a NA engine at low speeds .....but what low speeds.

Easy

[rasorinc]

Easy, unless your diesel and turbo are really old (mechanical) don't remove or put on. I have had race cars and the current electronic systems totally run engines and turbos so you have to have a race mechanic who can re-program the system computers for air pressure, volume, fuel input etc. and it's way over my head. I've watched them do it on my cars and they have added 150 hp playing with a computer. If you do not know how to do this you could blow every thing up or you may never get it started again. Stan PS these guys are few and far between and are $$$$$$$$

[Submarine Tom]

Simply turn down the boost a little.

-Tom

[powerabout]

Originally Posted by Easy Rider

Fred,
I feel really stupid ..forgot about the compression ratio. There must be a point down at the lower end (rpm) where the boost is insufficent to bring the BMEP up the NA engine level. So it would seem a turbo engine would be actually less efficent than a NA engine at low speeds .....but what low speeds.

Easy

if 50% power is without boost then removing it wont effect that 50% range, maybe even help as you have just a removed an inlet and exhaust restriction so maybe gain some efficiency

[FAST FRED]

"So it would seem a turbo engine would be actually less efficent than a NA engine at low speeds .....but what low speeds."


Below the RPM where there is a pound of boost or more.

This limits the bottom rpm of a turbo usually to above that of a NA.

While a NA may be happy at 1200 rpm (prime genset RPM) the turboed may need 1500rpm to get even a bit of boost.

FF

[Submarine Tom]

It depends on the size of the turbo and, more specifically, the housing size.

One can easily design an efficient turbo system.

-Tom