Wall Boundary Mass

September 24, 2003, 07:12

Hallo to everyone!

I am having a slightest problem. I would like to be informed about the following equation: Cw = A * dC/dn. Cw is what i am looking for, A is constant and dC/dn is the concentration along the normal vector. How can i program this equation knowing A and C in general?

Thank you very much!!

September 25, 2003, 05:52

What is Cw? Is that the concentration in the w direction (I have no clue)? I assume A is the area. Can you clear up your nomenclature.

September 25, 2003, 07:25

Hi!!

1. Cw is the concentration at the wall boundary. This value is calculated along the area normal vector n.

2. A is a constant value and is equal to (V-K)/D, where V=0.000004 cm/sec, K=0.00000002 cm/sec and D=0.00000005 cm^2/sec.

3. I know the concentration C along all different directions x, y, z and n from former iterations. From all these values i want those who satisfy the normal gradient to the boundary.

4. The equation is Cw = ((V-K)/D) * dC/dn.

Thank you a lot!!!

September 24, 2003, 07:12	Wall Boundary Mass	#1
Vasilios Papaioannou Guest Posts: n/a	Hallo to everyone! I am having a slightest problem. I would like to be informed about the following equation: Cw = A * dC/dn. Cw is what i am looking for, A is constant and dC/dn is the concentration along the normal vector. How can i program this equation knowing A and C in general? Thank you very much!!

September 25, 2003, 05:52	Re: Wall Boundary Mass	#2
Chetan Kadakia Guest Posts: n/a	What is Cw? Is that the concentration in the w direction (I have no clue)? I assume A is the area. Can you clear up your nomenclature.

September 25, 2003, 07:25	Re: Wall Boundary Mass	#3
Vasilios Papaioannou Guest Posts: n/a	Hi!! 1. Cw is the concentration at the wall boundary. This value is calculated along the area normal vector n. 2. A is a constant value and is equal to (V-K)/D, where V=0.000004 cm/sec, K=0.00000002 cm/sec and D=0.00000005 cm^2/sec. 3. I know the concentration C along all different directions x, y, z and n from former iterations. From all these values i want those who satisfy the normal gradient to the boundary. 4. The equation is Cw = ((V-K)/D) * dC/dn. Thank you a lot!!!

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