Mixing Time Estimator

Estimate the time required to achieve a uniform mixture in a vessel. This tool helps visualize how impeller speed, fluid properties, and geometry impact mixing efficiency in pharmaceutical processes.

Estimated Mixing Time (Tm)

0 min

Reynolds Number

0

Flow Regime

N/A

Tank Diameter (Est.)

0 m

Power Consumption

0 W

Assumptions & Steps:


            

Mixing Time Estimator

Welcome to the Mixing Time Estimator on PharmacyFreak.com. This tool is built to help you estimate the time needed to achieve proper mixing inside a tank. Whether you’re dissolving a drug, blending powders, or emulsifying liquids, understanding mixing time is essential.

This calculator gives you instant results, based on fluid properties, impeller speed, and tank geometry. It also tells you how much power your impeller uses and classifies the flow as laminar or turbulent using the Reynolds Number.

What Is Mixing Time?

Mixing time is the time required to achieve uniform distribution of all ingredients in a vessel. It is a key factor in pharmaceutical production and formulation.

Mixing time depends on:

  • Tank size

  • Fluid viscosity and density

  • Impeller speed and type

  • Flow regime (laminar or turbulent)

This tool brings all these variables together to calculate mixing time accurately and visually.

What Is Mixing Time?

Mixing time is the time required to achieve uniform distribution of all ingredients in a vessel. It is a key factor in pharmaceutical production and formulation.

Mixing time depends on:

  • Tank size

  • Fluid viscosity and density

  • Impeller speed and type

  • Flow regime (laminar or turbulent)

This tool brings all these variables together to calculate mixing time accurately and visually.

Key Features of the Mixing Time Estimator

✅ Regime-Based Calculation

The tool first calculates the Reynolds Number (Re) to determine the flow type:

  • Laminar Flow: Low energy, slow mixing

  • Turbulent Flow: Fast, efficient mixing

Based on the flow regime, it applies the correct formula for mixing time estimation.

✅ Impeller Type Presets

Select common impeller types like:

  • Rushton Turbine

  • Pitched Blade Turbine (PBT)

  • Hydrofoil

Each impeller has a preset Power Number (Np). You can also choose “Custom” to enter your own value.

✅ Power Consumption Output

Along with mixing time, the calculator tells you how much power (in Watts) your impeller will consume. This helps you understand the energy cost of mixing.

✅ Unit Flexibility

All input fields accept common units:

  • Volume – liters or m³

  • Diameter – cm or m

  • Viscosity – cP or Pa·s

  • Speed – RPM

The calculator handles conversions behind the scenes.

✅ Formula Transparency

The “Assumptions & Steps” box explains:

  • How Reynolds Number is calculated

  • Which mixing time formula was used

  • What each variable means

This helps you learn while solving real-world problems.

✅ PNG Export Option

Download your results, formulas, and flow classification as a clean PNG image. Add it to reports, assignments, or study notes.

How to Use the Mixing Time Estimator – Step-by-Step

Step 1: Enter Vessel and Impeller Details

  • Tank Volume (V): Enter in liters or cubic meters

  • Impeller Speed (N): Enter in RPM

  • Impeller Diameter (D): Usually about 1/3 of tank diameter

The tool estimates tank diameter assuming liquid height = diameter, a standard mixing tank shape.

Step 2: Choose Impeller Type

Pick from the dropdown. The tool will load the correct Power Number (Np). Use “Custom” to enter your own value if needed.

Step 3: Enter Fluid Properties

  • Density (ρ): In kg/m³

  • Viscosity (μ): In cP or Pa·s

These determine the Reynolds number and help classify the flow regime.

Step 4: Click “Calculate”

The results appear instantly. You’ll see:

  • Estimated Mixing Time (Tm) in minutes

  • Reynolds Number (Re)

  • Flow type (Laminar or Turbulent)

  • Power consumption in Watts

  • A full breakdown of steps and assumptions

Understanding the Output

🔄 Mixing Time (Tm)

This is the estimated time to reach 95% homogeneity. Shorter times mean faster production. Longer times may risk ingredient separation or inefficiency.

🌀 Reynolds Number and Flow Regime

  • Re < 10 = Laminar flow

  • Re > 10,000 = Turbulent flow

  • Between = Transitional flow (unstable)

Flow regime affects which formula is used.

⚡ Power Consumption

Shows how much power the impeller uses. Higher speed = more power (Power ∝ N³). Use this to estimate motor size and energy cost.

📘 Assumptions & Steps

Learn what formula was applied:

  • For laminar flow: Power and time depend heavily on viscosity

  • For turbulent flow: Power is more constant and mixing is faster

You’ll also see estimated tank diameter, impeller-to-tank ratio, and more.

Interpreting Flow Regimes

🟢 Laminar Flow (Re < 10)

  • Fluid moves in smooth layers

  • Common in viscous materials like gels or creams

  • Mixing is slow and energy-intensive

  • Useful in sensitive mixing where shear must be low

🔴 Turbulent Flow (Re > 10,000)

  • Fluid moves with swirling eddies and chaos

  • Common in water, ethanol, or thin solutions

  • Mixing is fast and efficient

  • Best for suspensions, dissolving salts, and general blending

Why This Tool Is Perfect for Pharmacy Students

Understanding mixing is essential in:

  • Granulation and tablet production

  • Solution prep and buffer blending

  • Emulsions and suspensions

  • Sterile solution preparation

This tool helps with:

  • Assignments

  • Lab reports

  • Viva questions

  • Scale-up case studies

Use it to test “what-if” scenarios—how changing speed or impeller type affects time and energy.