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Author Topic: more queries!!!!  (Read 9888 times)

MONAHAN STEAM MODELS

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Re: more queries!!!!
« Reply #25 on: December 22, 2009, 07:27:43 pm »

Ask and you shall receive! Don't ask and you still shall receive!  {-)  {-)  {-)
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Neil

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Re: more queries!!!!
« Reply #26 on: March 30, 2010, 09:20:10 am »

I was thinking of NMs comment above.

    
Re: more queries!!!!
« Reply #15 on: December 21, 2009, 01:37:50 AM »
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Twin poker burners would be fine and so would twin ceramic burners but in my ever so humble opinion if you have to use two burners to heat something up then my guess would be something else might be designed poorly.  Inocent

For example: the standard practice for most marine boiler makers when designing and building a larger diameter boiler is to use a heavier gauge copper tube etc, etc, etc.

UNQUOTE!

Did anyone notice that motor car engines now have lots of smaller diameter valves, to get the gas flow happening better than the old "Two Huge Valves"?

Goodness knows how many valves the Grand Prix engines now have. Is this not a matter of "Gas Flow"

I have made a few boilers in my lil' old workshop, quite a few. I also have made lots of burners, poker type, ceramic, you name it.

I do not have the skill to produce a (fantastic looking outfit), as does Mr Hemmens, Mr Monahan, Messrs Stuart et al. As it happens my toys work very well, but they don't look like the professionals' work.

The two smaller burners, have worked better for me, in larger boilers, rather than the one big one.

My opinion only.

I know someone will shoot me down, but, that's life, is it not?

Neil.
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gondolier88

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Re: more queries!!!!
« Reply #27 on: March 30, 2010, 01:53:54 pm »

Combustion- X amount fuel + Circa3X oxygen = perfect combustion.

If one large burner is putting too little fuel in, or is not getting enough air to it's entire surfsce then it will not burn as well as two smaller burners that use less fuel individually so will have enough air, and they have a smaller surface area so need less air individually too.

Simple really!

The analogy of gas flow isn't correct in the context you mention it- the more valve per piston you have then you can keep a constant velocity of gases in the plenumm chamber and exhaust, making the engine far more efficient as it doesn't have constant temperature and velocity changes.

Greg
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Don't get heated...get steamed up!

tobyker

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Re: more queries!!!!
« Reply #28 on: March 30, 2010, 03:07:27 pm »

4-stroke motor valves - use of more valves allows you to design a better shape of combustion chamber, get more valve area in and reduce reciprocating masses, thus reducing impact loads on the valve seats and stress on the valve gear, camshafts etc. The record may belong to Honda's racing bike with the oval pistons (NR750?)- I think it was 8 per cylinder. Why did they do it? because they could.
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gondolier88

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Re: more queries!!!!
« Reply #29 on: March 30, 2010, 10:38:39 pm »

Many IC engines use 8 valves per cylinder- Aston Martins supercarged straight 6 used in the DB7 pre-V12 used 48 valves on DOHC's.

Greg
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Neil

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Re: more queries!!!!
« Reply #30 on: April 03, 2010, 11:45:14 am »

I rest my case.

Neil.
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