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Both calculators run independently — change the inputs on either side to compare results.
Engineering
HVAC Duct Sizing Calculator
Calculate the required diameter or dimensions of HVAC ducts based on air flow rate and design velocity. Use this when designing ventilation systems to balance air delivery with noise and pressure loss constraints.
Fill in the required fields to see your result.
Engineering
Reynolds Number Calculator
Calculate the Reynolds number — the dimensionless ratio of inertial to viscous forces in a flowing fluid — to determine whether flow is laminar, transitional, or turbulent. Use it for pipe-flow design, mixing analysis, drag prediction, and selecting the right friction-factor correlation.
Fill in the required fields to see your result.
Key differences
| HVAC Duct Sizing Calculator | Reynolds Number Calculator | |
|---|---|---|
| Category | Engineering | Engineering |
| Inputs required | 4 | 4 |
| Result | Duct Dimension (inches) | Reynolds Number |
| What it does | Calculate the required diameter or dimensions of HVAC ducts based on air flow rate and design velocity. Use this when designing ventilation systems to balance air delivery with noise and pressure loss constraints. | Calculate the Reynolds number — the dimensionless ratio of inertial to viscous forces in a flowing fluid — to determine whether flow is laminar, transitional, or turbulent. Use it for pipe-flow design, mixing analysis, drag prediction, and selecting the right friction-factor correlation. |