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Old   May 19, 2009, 23:19
Default A problem about initialization
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zhangyuan
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Hi,everyone
I need your help, I have a problem in modeling the steady gasification of coal water slurry. The inlet pressure of the oxidizer is 8.1Mpa, and the mass flow rate of the oxdizer is 15.72kg/s, and the velocity is 55m/s. But if the velocity is defined as the boundary condition of the inlet and initialized, the mass flow rate of the oxidizer is 129kg/s in the result of my simulation, more than 15.72kg/s. And if the mass flow rate is defined as the boundary condition of the inlet and initialized, the velocity of the oxideser is 2.88kg/s, less than 55m/s. I want to know why? I try it again and again, but get the same result. Can anyone help me? Thank you!
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Old   May 20, 2009, 01:17
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I do not have much knowledge about multiphase flows but seems you have some problems with the specific model that you employ for your computations to obtain such a vast difference in the predictions. Where do you get your parameters from ? Also are you sure you the models that you employ has shown to produce good results for the gasification studies ?
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Old   May 20, 2009, 03:26
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Quote:
Originally Posted by harishg View Post
I do not have much knowledge about multiphase flows but seems you have some problems with the specific model that you employ for your computations to obtain such a vast difference in the predictions. Where do you get your parameters from ? Also are you sure you the models that you employ has shown to produce good results for the gasification studies ?
Thank you
I read many articles about simulation of the gasifier of the coal water slurry, and they are similar with what I am doing. So I use the same models as them. Non-premixed combustion model is used to simulate the chemical reactions and DPM model is used to simulate the paticle phase in my simulation. I am sure of them.
The parameters what I am using in my simulation are from the industry.
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