On Apr 23, 12:23 am, Matt Colie wrote:
Rahul,

A great number of real engines (bore6'[150mm]) have cooling features
under the piston crown, even some small truck engines have them. Few
are machined, but many are cast of forged that way.

If you are looking for the engines that actually circulate coolant
inside that piston, that is only common in crosshead design engines that
have a separate piston rod that is attached to a crosshead bearing and
that is attached to the connecting rod to the crankshaft.

This type of engine is common in the 1m bore class engines. I have seen
it as small as 600mm bore class. These engines have a coolant feed to
the crosshead and then coolant is piped up the piston rod to the piston
and returned to the crosshead.

Try some searching on Sulzer and Burmeister&Wain. They both build
engines this size and type.

Matt Colie



Rahul wrote:
Has anyone heard about pistons with cooling channels machined inside
them?? I recently came across such kinds of pistons that are used in
big marine engines. Can someone tell me the approximate stroke and
bore of these pistons?? what will be the typical size of a connecting
rod used in marine engines??
Thank you- Hide quoted text -

- Show quoted text -

dazed and confuzzed - thank you for your reference to the world's
biggest diesel engine. I have actually seen it one year ago, but
forgot that it had piston cooling

Matt colie - Your information is really valuable and i got more info
by searching for sulzer pistons.. You have really helped me a lot for
my project.. As I am doing a heat transfer analysis on pistons, i
needed these information about the piston stroke, bore and the cooling
channel dimensions..

What can be the approximate values for the following?

Bore - 60cm??
Stroke - 90cm??
Engine rpm - 100
cooling channel dia - 1cm??
Inlet velocity of water or oil - 1m/s??
Piston crown temperature - 500 K??

As of now, I have modeled a 3d cooling channel which has an
inlet(vertical) at one extreme extending onto the piston crown, taking
a semicircular path around the underneath of the crown(horizontal) and
an outlet(parallel to the inlet) at the other extreme.. Is this
atleast remotely realistic??