Project of the Month built by Rustkolector

Help Support Home Model Engine Machinist by donating using the link above or becoming a Supporting Member.
Home Model Engine Machinist > Building Them > General Engine Discussion > Coolant volume vs. displacement or HP

Reply
 
Thread Tools
Old 02-13-2018, 10:52 PM   #11
johnlaudano
 
Join Date: Jan 2011
Posts: 47
Liked 46 Times on 17 Posts

Default

Gentlemen,
Great discussion and great links. The engine would power another mahogany boat. I feel better about small water jackets now and I like the thermostat idea. Lots more drawing to go.
John


johnlaudano is offline  
 
Reply With Quote
Old 02-14-2018, 04:33 AM   #12
Rustkolector
 
Join Date: Aug 2008
Location: Central NY
Posts: 250
Liked 84 Times on 40 Posts

Default

John,
In my mind, a fresh water cooling jacket should be more on the generous side rather than the thin side. Thin jackets will foul more quickly if the water clarity is poor. An intake water strainer might also be advisable.

Set up your engine running at the design load and RPM with a summer pond temp intake water supply. Adjust the flow or pump speed to get a 9-12 degree F differential temperature across the engine cooling system. This will provide an optimum coolant flow to cool your engine under the warmest expected operating conditions. A bypass thermostat would be ideal, but I have never seen one for small scale use.

Another issue is that a smooth running 360 degree crankshaft twin cylinder engine will create significant crankcase pressure pulsations and require a check valve type crankcase vent. This will likely trap blow-by moisture in the crankcase making the oil milky. It gets a little better as the rings seat, but doesn’t completely go away. Design for easy crankcase oil draining and flushing with WD-40 after use. A good hot running engine will combat the moisture build-up and gasoline produces a little less moisture in the combustion gases than propane.

Jeff


Rustkolector is offline  
 
Reply With Quote
Old 02-14-2018, 12:57 PM   #13
Cogsy
 
Cogsy's Avatar
 
Join Date: Jul 2012
Location: Perth, Western Australia
Posts: 1,864
Liked 504 Times on 390 Posts
Likes Given: 495

Default

Quote:
Originally Posted by BaronJ View Post
Hello Al,

I was never great at spelling Its way over 50 years since I did anything like this, so that gives you an idea of how little I remembered from what was then Chemistry / Physics... I'm glad I went for Electrickery
Hi Baron,

You picked an unlucky word to mis-spell, adsorption is a confusingly similar, but physically quite different process and can be easily confused with absorption, which is why I mentioned it.

I have exactly the opposite problem to you, I'm hopeless with electricity (as evidenced by my occasional self inflicted shocks) but seeing as I'm a physicist, physics and thermodynamics is right in my wheelhouse... each to his own I guess. Have a good one.
__________________
Al.
______________________
I'd like to be a perfectionist, but I lack the patience...not to mention the skill...
Cogsy is offline  
 
Reply With Quote
Old 02-14-2018, 11:32 PM   #14
johnlaudano
 
Join Date: Jan 2011
Posts: 47
Liked 46 Times on 17 Posts

Default

Jeff, I received your PM. I sent you two replies but can't verify if they were posted. The web site seems to be having a problem.


johnlaudano is offline  
 
Reply With Quote
Reply


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
How to calculate volume of hole werowance General Engine Discussion 11 09-29-2015 05:22 PM
Calculating compression ratio from differences in volume digiex-chris General Engine Discussion 11 03-08-2015 07:09 PM
Air volume calc Ripcrow General Engine Discussion 4 07-25-2013 04:44 AM
boiler water volume John Rudd Boilers 6 10-09-2010 08:49 AM
Sterling volume/stroke data and opinions TheDogofWar General Engine Discussion 5 10-09-2009 01:14 PM



Newest Threads






- Top - Member List