Effective Stack Height

What is this formula?

This formula calculates the effective stack height by adding the physical stack height and the plume rise above the stack outlet.

When to use it

Use it in atmospheric dispersion calculations when the pollutant plume rises above the stack due to exit velocity, buoyancy, and atmospheric conditions.

Example

Data:

Hstack = 45 m

dH = 18 m

Formula:

H = h + Δh

Substitution:

H = 45 + 18

Result:

H = 63 m

Applications

Gaussian plume modeling, stack design, air quality impact assessment, industrial emissions studies, environmental permitting, and atmospheric dispersion analysis.

Note

This formula is exact as a definition, but plume rise itself is usually estimated using empirical correlations. The effective stack height depends on stack gas velocity, temperature difference, atmospheric stability, wind speed, and nearby building effects.