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Old 11-05-2009, 06:53 PM   #11
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Rick-

I added the curve in my response after yours.....

I do agree that the relationship (HP vs RPM) is not exactly linear and that in my simplistic explanation I used engine HP not prop demand (Prop Load) curve which is the most technically correct.

I was just trying to give Howard a simple method to calculate % load based upon what is normally talked about around the dock with a very simplistic explanation. I agree it's not the most accurate methodology, but for "discussion" purposes, I feel it's acceptable.

If I was considering a re-power of my boat, I would probably use a finer calculation method.

So Howard, if you need an answer that needs to be closer than say.... +/- 10%....., then don't use what i originally posted. You'll need to go out and find the actual curve for your engines and do some cyphering with something more than simple arithmetic.

Sorry for the confusion.....anyone seen my retired pocket protector...
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Old 11-05-2009, 06:58 PM   #12
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Originally Posted by JD5652 View Post
Rick-

I added the curve in my response after yours.....

I do agree that the relationship (HP vs RPM) is not exactly linear and that in my simplistic explanation I used engine HP not prop demand (Prop Load) curve which is the most technically correct.

I was just trying to give Howard a simple method to calculate % load based upon what is normally talked about around the dock with a very simplistic explanation. I agree it's not the most accurate methodology, but for "discussion" purposes, I feel it's acceptable.

If I was considering a re-power of my boat, I would probably use a finer calculation method.

So Howard, if you need an answer that needs to be closer than say.... +/- 10%....., then don't use what i originally posted. You'll need to go out and find the actual curve for your engines and do some cyphering with something more than simple arithmetic.

Sorry for the confusion.....anyone seen my retired pocket protector...

Thank you for the clarification.
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Old 11-05-2009, 07:03 PM   #13
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Thumbs up Thank you for Explanations

Guys, thanks! I think the "simplified" explanation of "load" is suitable for my purposes. I appreciate all the thought and effort. Thanks, again!
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Old 11-05-2009, 07:11 PM   #14
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Wow, I'm glad I didn't get involved in that one! Frank
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Old 11-07-2009, 08:41 AM   #15
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Fritz-

Wow!....maybe back in the day...but I retired by pocket protector a long time ago...what about "departure from nucleate boiling" (DNB)....
Something to do with heat transfer of fuel rods and the insulating effect of steam. While I did a little commercial diving in nuke plants, that stuff is over my head.
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