Calculators
Vessel Holdup & Residence Time
Total working volume (cylindrical body + 2 heads), partial-fill volume for a horizontal drum at a given liquid level, and residence times for liquid and gas flow. Head types: 2:1 ellipsoidal or hemispherical.
Formulas: 2:1 ellipsoidal head V = (π/24)D³; hemispherical head V = (2π/3)R³. Horizontal partial-fill uses the circular segment area A = r²(acos((r-h)/r) - (r-h)/r · √(1-((r-h)/r)²)) × L. Residence time τ = V / Q. Assumes flat tan lines; real-world heads add a small straight flange that's usually negligible for holdup work.
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