Process Design
Tank Turnover Calculator
Tank turnover (or hydraulic turnover) measures how many times the tank volume is replaced by the flow passing through it. This calculator provides turnover rate, turnover time, and total turnovers over a specified period. It is a simple hydraulic calculation — it does not model mixing quality, dead volume, or residence-time distribution.
TypeInteractive calculator — separate from unit conversions
Calculator
Result
Turnover time4 h
Turnover rate0.25 /h
Total turnovers2
Formulas
Turnover rate
turnover rate = Q / V
Turnover time
turnover time = V / Q
Turnovers over period
turnovers = Q × t / V
Diagram
Worked example
A 100 m³ tank receives flow at 25 m³/h. What is the turnover time? How many turnovers occur in 8 hours?
- 01Turnover time = V / Q = 100 / 25 = 4 h
- 02Turnover rate = Q / V = 25 / 100 = 0.25 /h
- 03Turnovers in 8 h = Q × t / V = 25 × 8 / 100 = 2
Result
Turnover time is 4 h. Turnover rate is 0.25 per hour. In 8 hours, the tank turns over 2 times.
FAQ
Is this a mixing quality model?
No. Turnover is a simple hydraulic ratio. Achieving one complete turnover does not guarantee uniform mixing. Mixing quality depends on impeller design, baffles, and flow pattern.
Does this calculate residence-time distribution?
No. Residence-time distribution (RTD) requires tracer studies or CFD modelling. This calculator gives the nominal hydraulic turnover only.
Does this account for dead volume?
No. Enter the effective volume only. If the tank has significant dead zones, reduce the volume input accordingly.
Does this model reactions in the tank?
No. This is a hydraulic turnover calculator. Reaction kinetics, conversion, and selectivity are not included.