Carlin,Beckett,Riello

BDR529

Any research done on who produces the hottest flame if there is such a thing?

It's a loaded question with many variables.

What is the max temp out of oil heat not BTU's since that has been cut?
Dose temp even change or is it a constant through out the firing range?

EBEBRATT-Ed

I would think the burner with the highest Co2 with the same 0 smoke would be the best burner. But it's not just the burner it is the environment the oil is burned in and how well the heat exchanger absorbs the heat.

Perfect Co2 is around 15%. I have seen burner burn clean at 13%. All 3 of the above burners are capable of doing that under the right conditions

STEVEusaPA

What’s the purpose of these questions?
-Any of the burners with the exact same combustion numbers, especially excess air, Flame temperature (or higher/maximum temperature) has more to do with the construction of the combustion chamber and heat exchanger.
-Don’t understand your second question. But I’m pretty sure @Jim Davis would know temperatures.
-I’m sure temperatures change as heat transfer takes place, especially in something like a cold start boiler, going thru and coming out of condensing mode.

Jamie Hall

Hottest flame? Or most heat? There's a huge difference. For one thing, the flame temperature is widely variable. Way too many variables.

BDR529

A perfect Co2 15%?! Even at 13% there is a good chance of a soot issue. I would even think at 13% my flame would be slightly hotter, maybe a degree or 2.

All the burners are very good. However, far from similar

The propose of the questions is because I don't know the flame temp of oil heat. Never really thought about it.

Has temp changed more or less with the blended flues or not?
Has it differed as much as Co2 readings or do they mirror one another?

Chamber construction, refractories could be considered combustion aids.

Been thinking the Buderus BE125 runs a cooler flame than a equivalent Riello.

450 degree stack temp.. 800 degree flame?

BDR529

Jamie Hall said:

Hottest flame? Or most heat? There's a huge difference. For one thing, the flame temperature is widely variable. Way too many variables.

Yes!! Alot of radiational heat off these flames.

But how do you change flame temp? Is it not a constant no matter at what rate?

Jamie Hall

The actual gas temperature at the point of reaction may be several thousand degrees Fahrenheit. That really doesn't change much at atmospheric pressures (it does change at elevated pressures). But that temperature drops very quickly in the environment of the flame; initially by conduction with the cooler gas immediately surrounding (and thus turbulence in the flame makes a big difference) but also by direct radiation to the chamber walls, and so geometry of both the flame and the geometry and nature of the walls makes a difference. Then when you get a little farther away from the actual flame front, conduction between the now very hot gas and the chamber walls becomes more and more important as the gas temperature drops going through the combustion chamber and gas passages.

The combustion temperature at the flame front is affected by fuel type, but any fuel which is primarily single covalent bonded (which is all normal fuels, oil or gas) will be in the same range. Fuels which have a large fraction of double bonds (such as propylene) will have a higher flame temperature, and the only more or less normal fuel with a triple bond (acetylene) may well be over 10,000 Fahrenheit at the flame front.

With normal fuels, none of that matters -- what matters is the overall ability of the sink -- the boiler or furnace -- to effectively absorb the heat from the flame.

STEVEusaPA

Flame in a lined chamber Can go up to almost 3000 degrees

EBEBRATT-Ed

@BDR529

I did not say you can run any burner at 15%Co2. 15% is stokiometric combustion which is "perfect" combustion which can never be acheved . You only get that when every molucule of oil is mixed with air and burns completely.

Stack temperature has little to do with any of the three burners properly adjusted. It has much more to do with the heat exchanger

BDR529

Fantastic info!! Forgot about those flame charts. Haven't thought about this in years. Fix the problem and on to the next..

Did they ever do a flame chart on bunker fuel?

BDR529

The sink of the burner to the boiler/furnace I think is an interesting subject on its own. Direct vented appliances to say the least.

Nevermind burners but, what makes a Hago run so much better in some circumstances?

EBEBRATT-Ed

Not all nozzles are the same even if the spray angle and pattern match. The nozzle who's spray pattern matches the burner air flow pattern is usually the best choice. This can only be found by testing

BDR529

EBEBRATT-Ed said:

Not all nozzles are the same even if the spray angle and pattern match. The nozzle who's spray pattern matches the burner air flow pattern is usually the best choice. This can only be found by testing

Yes, thats a given. Any study on cutting them in half and finding those small differences with a scope? Something that can be physically seen..

What makes a Danfoss/Hago HFD so different?

EBEBRATT-Ed

It's not something that can be predicted. We used to call it a nozzle substitution test. A box of nozzles and a burner and you worked with it until you got the best results.Oil pressure, temperature, combustion chamber geometry all effect how a burner burns.

That's what the burner manufacturers do and they are wrong sometimes. Not an exact science.

Even the oil changes from location to location

STEVEusaPA

All of that and then throw in the temperature of the oil too.

BDR529

The oil has been a big factor. Had a Riello a coulpe of months ago that made me think about all of those subtle differences.

BF3 with .70x80B @ 130 PSI been no problem and runs great for 5 yrs. Then started rumble, erradic flame. That nozzel has been gold in these boilers.

Had to run a .65x80B @ 150psi now smooth as silk with good numbers. But.. I know Riello's do not like bio blends. The room for error is tight to say the least.

It dose reinforce how diffent each install has it's own personality.

STEVEusaPA

BDR529 said:

...I know Riello's do not like bio blends...

Says who?

BDR529

Says Riello

STEVEusaPA

Where? Do you have a link to a white paper?

BDR529

I talked directly to Riello on a couple of occasions. no paper was offered. I don't see a BF3 listed anyway.

captainco

My 1926 oil handbook shows the maximum flame temperature of oil at 4600 degrees. LP is 3900 degrees, natural gas is 3600 degrees. Other charts show oil flame temps around 4000 degrees. Although I believe in the higher number I haven't ever measured it. The burner doesn' t matter.
Regardless, all fuels burn at their maximum temperature with the lowest O2 or highest CO2. When you see someone advertising a burner that has a lower flame temperature you need to avoid it. These are usually Low NOX burners and use more energy because we are trying to produce less Laughing Gas.
I found out back in the 80's the best nozzle is the one that produces the least CO (carbon monoxide) when the burner lights, while it runs and when it shuts down. Nozzles can be bad right out of the box. I remember going through as many as 8 nozzle on one job before I got the CO below 100 ppm at all stages. I have also found that if a nozzle is producing less than 25 ppm when it starts, runs and shuts down, it is a major mistake to replace it. Note: CO and Smoke on oil are totally different.

BDR529

Patience of a saint! 8 nozzles! Throw that out the window nowadays.

Burn through that tank and on the next load it will be different. Zero consistency.

Man, I miss the 80's things really were simpler.

captainco

That was the 80's. Came to find out the nozzle company was using some type of mineral oil to test their nozzles and it messing up the swirl ports.
Learned very quickly that the consistency of nozzle angle and spray pattern were not necessarily dependable.

Steamhead

captainco said:

My 1926 oil handbook shows the maximum flame temperature of oil at 4600 degrees.

Which book is this?

BDR529

Interesting, What did that burner look like in 1926? Got any pics?

How do you think the mineral oil compairs to the Bio-blends?

captainco

I have to find the book it is packed away after I moved a few years ago.. Atomized oil burners were patented around 1925 but I don't have a picture. I did see something on the internet.

Actually the oil was closer to vegetable oil and started to harden. It was difficult to convince by boss that we had to switch nozzle brands after he had been selling them for 40 years.