Does a 50× volume ratio require 50× power?

Not from this calculation. Power depends on impeller geometry, speed, material properties, and flow behavior. Obtain equipment data and verify the process at scale.

Does equal tip speed give equal mixing?

No. Circulation, shear distribution, mixing time, and heat transfer can change with scale. Matching tip speed preserves only the impeller peripheral velocity.

Can I derive impeller diameter from batch volume?

Only with justified geometric similarity. Enter measured or specified diameters here, especially when pilot and production equipment differ.

What if the calculated speed exceeds the drive rating?

Do not use that speed. Review the mixer selection and scale-up criterion with the equipment supplier, then test an achievable operating point.

Mixing, Blending & Industrial Batch Processing calculator

Mixer Scale-Up Ratio Calculator

Compare production volume with a pilot batch and preserve its impeller tip speed. Enter both batch volumes, both impeller diameters, and the measured pilot speed.

What this calculator does

Compare pilot and production batch volumes and calculate a production speed that preserves measured pilot impeller tip speed.

Formula used

Volume ratio = production batch volume ÷ pilot batch volume
Diameter ratio = production impeller diameter ÷ pilot impeller diameter
Matched production speed = pilot speed × pilot diameter ÷ production diameter
Tip speed = π × pilot diameter × pilot speed ÷ 60,000

Inputs explained

Pilot Batch Volume: Actual pilot working batch volume from the trial record.
Production Batch Volume: Planned production working volume for the same formulation.
Pilot Impeller Diameter: Outside diameter of the active pilot impeller.
Production Impeller Diameter: Outside diameter of the corresponding production impeller.
Pilot Impeller Speed: Measured pilot speed at the documented trial operating point.

How to use the result

Best suited to pilot-to-production planning, impeller speed comparison.
Different impeller shapes or fluid behavior can invalidate process comparisons. This does not predict production power, blend time, heat transfer, or product quality.

Common questions

Does a 50× volume ratio require 50× power? Not from this calculation. Power depends on impeller geometry, speed, material properties, and flow behavior. Obtain equipment data and verify the process at scale.
Does equal tip speed give equal mixing? No. Circulation, shear distribution, mixing time, and heat transfer can change with scale. Matching tip speed preserves only the impeller peripheral velocity.
Can I derive impeller diameter from batch volume? Only with justified geometric similarity. Enter measured or specified diameters here, especially when pilot and production equipment differ.
What if the calculated speed exceeds the drive rating? Do not use that speed. Review the mixer selection and scale-up criterion with the equipment supplier, then test an achievable operating point.

Last reviewed 2026-10-01.