Question

A differential nitrogen pressure exists across a 2-mm-thick steel furnace wall. After some time, steady-state diffusion of the nitrogen is established across the wall. Given that the nitrogen concentration on the high-pressure surface of the wall is 2 kg/m3 and on the low-pressure surface is 0.2 kg/m3, calculate the flow of nitrogen through the wall (in kg/m2⋅h) if the diffusion coefficient for nitrogen in this steel is 1.0 × 10-10 m2/s at the furnace operating temperature.

Answer 1

`J_x = 0.324 * 10^(-3)\ kg/m^2.h`

Step-by-step explanation:

given,

thickness of steel furnace = 2 mm

high- pressure surface = 2 Kg/m³

low-pressure surface = 0.2 kg/m³

coefficient for nitrogen in this steel = 1.0 × 10⁻¹⁰ m²/s

`J_x = -D[(-(C_h-C_l))/(\chi_0)]`

`J_x = -(1* 10^(-10))[(-(2-0.2))/(2 * 10^(-3))]* 3600 s/h`

`J_x = 0.324 * 10^(-3)\ kg/m^2.h`

the flow of nitrogen through the wall is equal to
`J_x = 0.324 * 10^(-3)\ kg/m^2.h`