Calculation of flame Strain Rate

[John Gordon]

Hi there, 

I have query with regards to how strain is actually calculated in Cantera for the counter diffusion flame.

I have a simulation set up and I can use the function f.strain_rate('mean') to return the mean value
But I was also trying to calculate the mean strain rate based on:

1. Using the (mean velocity profile / mean of flame grid)

2. Using strain_rate = np.gradient(velocity_profile, z)
then using mean_strain_rate = np.mean(strain_rate)

But all these methods give a different answer.

If anyone could shine any light on this matter, it would be greatly aprpeciated.

Kind Regards, 

John Gordon 

[Ray Speth]

Hi John,

The definition is given in the documentation for the strain_rate method. The “mean” strain rate is the total change in velocity between the inlet and outlet, divided by the width of the domain.

Regards,
Ray

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