Blood Flow Poiseuille Calculator
Enter vessel radius, length, blood viscosity, and pressure difference to calculate volumetric flow rate using the Hagen-Poiseuille equation.
Vessel Parameters
Inner radius of the vessel lumen.
Pressure drop from inlet to outlet.
Whole blood ≈ 0.0027 Pa·s; plasma ≈ 0.0012 Pa·s.
Quick Presets
Enter vessel parameters and click Calculate.
Volumetric Flow Rate (Q)
µL/min
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mL/min
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mL/s
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Radius (SI)
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Length (SI)
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ΔP (SI)
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Viscosity
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Vascular Resistance
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Formula Used
Q = πr⁴ΔP / (8ηL)
Typical Vessel Parameters
| Vessel | Radius | Typical flow |
|---|---|---|
| Aorta | 10–15 mm | 4–5 L/min |
| Large artery | 1.5–5 mm | 50–500 mL/min |
| Arteriole | 5–50 µm | < 1 mL/min |
| Capillary | 2–5 µm | ~1 µL/min |
Educational use only. Poiseuille's law assumes steady laminar Newtonian flow in a rigid straight cylinder. Actual blood flow is pulsatile, non-Newtonian, and occurs in elastic, curved vessels.
Summary
Enter vessel radius, length, blood viscosity, and pressure difference to calculate volumetric flow rate using the Hagen-Poiseuille equation.
How it works
- Enter the vessel inner radius in micrometers (µm) or millimeters (mm) using the unit selector.
- Enter the vessel length in millimeters or centimeters.
- Set the pressure difference (ΔP) across the vessel in mmHg or Pa.
- Set the dynamic viscosity of blood — the default is 0.0027 Pa·s (whole blood at 37°C).
- Click Calculate to apply the Hagen-Poiseuille equation: Q = (π × r⁴ × ΔP) / (8 × η × L).
- Results are shown in µL/min, mL/min, and mL/s for easy comparison.
Use cases
- Physiology students studying vascular resistance and flow dynamics.
- Biomedical engineering coursework on cardiovascular fluid mechanics.
- Comparing the effect of vessel radius changes (vasoconstriction/dilation) on blood flow.
- Calculating flow in capillaries, arterioles, or larger conduit vessels.
- Research and lab exercises estimating flow under known pressure gradients.
- Exploring how viscosity changes (e.g. anemia, polycythemia) affect perfusion.