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Friction Factor Calculator

Find the Darcy-Weisbach friction factor for laminar or turbulent pipe flow from the Reynolds number and pipe roughness. Essential for calculating head loss in piping system designs.

Reynolds Number

Relative Roughness

Pipe Condition

Temperature Factor

Flow Regime

Fill in the required fields to see your result.

Fluid Mechanics

Tank Drain Time Calculator

Calculate how long it takes to drain a tank from one liquid level to another through a bottom orifice. Ideal for sizing drain valves, planning tank cleanouts, or verifying emergency drainage rates.

Initial Liquid Height (m)

Final Liquid Height (m)

Tank Cross-Section Area (m²)

Drain Orifice Area (m²)

Discharge Coefficient

Fill in the required fields to see your result.

Key differences

	Friction Factor Calculator	Tank Drain Time Calculator
Category	Fluid Mechanics	Fluid Mechanics
Inputs required	5	5
Result	Friction Factor	Drain Time (seconds)
What it does	Find the Darcy-Weisbach friction factor for laminar or turbulent pipe flow from the Reynolds number and pipe roughness. Essential for calculating head loss in piping system designs.	Calculate how long it takes to drain a tank from one liquid level to another through a bottom orifice. Ideal for sizing drain valves, planning tank cleanouts, or verifying emergency drainage rates.