Formula & worked example
TDH=Δz+ΔP/(ρg)+hf+Δ(v²/2g).
A system with 20 m static rise, 8 m pressure head and 12 m losses needs about 40 m TDH before velocity correction.
Plant engineering calculator · Updated Sep 17, 2026
Calculate pump TDH by combining elevation, vessel-pressure difference, suction/discharge friction and velocity-head change with fluid specific gravity.
TDH=Δz+ΔP/(ρg)+hf+Δ(v²/2g).
A system with 20 m static rise, 8 m pressure head and 12 m losses needs about 40 m TDH before velocity correction.
Calculate pump TDH by combining elevation, vessel-pressure difference, suction/discharge friction and velocity-head change with fluid specific gravity.
Use the result as an engineering screening and cross-check. Confirm final selections against manufacturer performance data, design conditions, applicable standards and local code.
Plant calculations can move materially with pressure, temperature, fluid properties, diversity and operating conditions. Visible assumptions make the result auditable.