Natural gas combustion
 

Hi all,

Just getting started on natural gas combustion in a melt furnace. Can anyone tell me if I can simulate the natural gas combustion with the methane/air database in fluent, thereby effectively simulating methane/air but with acceptable result for natural gas conbustion?

I think I might be able to do this as the natural gas contains 94% methane??? But not sure if this is appropriate for CFD simulation?

If I can do this, could someone give me a reference?

Thanks

Tom

Re: Natural gas combustion
 

Hi,

well I'll give you a typical scientific answer. It depends on what you want.

Be more specific in what are you after. Is it temperature field? Is it concentration of CO,NOx? Is it premixed or diffusion combustion?

matej

Re: Natural gas combustion
 

Hi matej,

It's diffusion combustion I'm simulating using the two-step eddy dissipation model. An overall picture of what is going on inside the furnace is what I want.

I want to gain an understanding of what is going on inside the furnace. The property values don't have to be exact (although that would be nice) but the flow field and combustion trends must be right. The understanding gained is used to design a control system, so the flow patterns are important to us.

Thanks for your help,

Tom

Re: Natural gas combustion
 

If you want an overall picture, temperatures and velocity field, your two step eddy dissipation model is a good start. eddy dissipation models convergence is quite good. It will give you the basic idea what is going on. The concentration of main products like H2O and CO2 would be OK. Don't expect to have correct CO and NOx. It's OK to use it for your natural gas. Just do not forget to have the same power in the furnace.

matej

Re: Natural gas combustion
 

Thanks matej,

What do you mean by 'do not forget to have the same power in the furnace'? Do you mean, that if the furnace is operating at 30MW for example, that the simulation should also be at 30MW?

Also, do you know of a paper that simulates methane combustion to represent natural gas, so that I can reference it?

Thanks again,

Tom

Re: Natural gas combustion
 

Yes, I mean the same power. Your natural gas is not 100% methane.

You can find the papers at www.sciencedirect.com . There's also lot of ASME papers with industrial application of CFD.

matej

Re: Natural gas combustion
 

Thanks alot matej, you've been a great help!

Tom

Re: Natural gas combustion
 

hello, I have done lot of work with methane and natural gas combustion, i could be good help, better drop me an email on zxaar@yahoo.com, we can discuss this there in detail