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Re: Multi Fuel Burner MB 10/18

Posted: Thu May 31, 2018 7:02 pm
by fredrosse
A 75mm x 100mm double acting single cylinder engine produces around 3 horsepower at 350 RPM, with cylinder mean effective pressure of 70 PSI. That would correspond to about 120 PSI steam chest pressure, with 60-70% cutoff.

That would require a fire capacity of about 182,000 BTU per hour, or 53 kW firing rate. That corresponds to an overall plant efficiency of 4% (Power Energy Output / Fuel Energy Input). With oil firing that is about 1.2-1.4 US Gallons per hour

Buy the way, a power or energy rate has units of kW, not kWh

Re: Multi Fuel Burner MB 10/18

Posted: Thu May 31, 2018 8:47 pm
by dampfspieler
Hi Fred,
Buy the way, a power or energy rate has units of kW, not kWh
look this page You are currently converting energy units from kilocalorie to kilowatt hour.

Hi Ron,

the burner was designed for use in a field kitchen with wide fireboxes for military and emergency measures and in the operating manual (given with every burner) the right flame ist called by the manufacturer (WEBASTO) as a "most yellow one".
The outer conditions in the shown test ("Does the burner work?") are very different from burning in the firebox of a boiler.

I will test my burner and show the right setup for this type. The fuel vaporises in the unit of the two pipes and the drum by the heat of the flame. I think it was a bit cold for good vaporising.

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Best Dietrich

Re: Multi Fuel Burner MB 10/18

Posted: Thu May 31, 2018 10:45 pm
by DetroiTug
Hi Dietrich,

It looks like a very well designed unit and with that much engineering it has more than likely been designed satisfactorily.

Yes, when it's in a combustion chamber it will most likely burn much better. That color flame is cold and creates soot. Yes, outside air may have been messing with the vaporization. On my car, it takes considerably longer to heat the vaporizer when it is 32F or 0C. And to create steam as well.

I was wondering about the S-shaped plate and really not serving much purpose as it is positioned in the video, I think it would do more for post mix vaporization of the burner was flipped over.

The pilot lights (vaporizing camp stove burners) that I use are Optimus Nova brand. They simply have and .008"? orifice that squirts a tiny stream of fuel up on a flat plate vaporizer and they burn nice and blue with a variety of fuels. I use two of them under my vaporizer coil, which work great and solve several standing pilot light issues, i.e. if one pilot goes out the other will relight it and the car can run on one pilot only, once hot.

Serpolet of French steam car fame used this type burner heads on a grid manifold for the main burner with good results, he designed one of the best running steamcars ever built. One of his designs had no steam throttle, rather the burner was throttled and the generator made steam instantly on demand, it was sychronized with the feedpump as well, very ingenious design. It had troughs along each row of burner heads that alcohol was poured in to to preheat the plate vaporizers.

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Re: Multi Fuel Burner MB 10/18

Posted: Fri Jun 01, 2018 1:09 am
by Lopez Mike
Typed kW and the stinking spell checker snuck in behind me and changed it. I know better.

And it does seem as though this burner might not be powerful enough for many of our boats. Too bad. I like it.

I guess it's back to fooling with a wood pellet stoker.

Re: Multi Fuel Burner MB 10/18

Posted: Fri Jun 01, 2018 6:45 am
by fredrosse
"look this page You are currently converting energy units from kilocalorie to kilowatt hour."

Yes, that conversion is units of energy, with no reference as to the time for the energy conversion or energy transfer to occur.

In the rating of burners we must use units of "energy rate" or energy per unit of time, such as Watts, kilowatts, BTU per hour, kilo-calories per hour.

Using proper units of measure, and their conversions is a constant source of errors within the engineering world, so being dimensionally correct is a valid requirement.