Units Overview
The Process PI Units Module provides a consistent framework for handling physical and chemical units commonly used in process and chemical engineering.
This section gives an overview of all supported quantities, conversion rules, and their role in engineering calculations.
📏 Fundamental Units
- Length: Handles different units of distance such as meters, centimeters, inches, and feet.
- Pressure: Conversion between Pascal, bar, atm, psi, and other industrial units.
- Temperature: Celsius, Kelvin, Fahrenheit, and Rankine conversions.
- Mass: Mass measurements in kg, g, lb, ton, etc.
- Volume: Cubic meters, liters, gallons, barrels, and more.
- Area: 2D measurements such as m², cm², and ft².
- Diameter: Specialized length property for circular geometries.
💨 Flow & Density
- Volumetric Flow Rate: Volume per unit time (m³/s, L/min, gpm).
- Mass Flow Rate: Mass per unit time (kg/s, lb/h).
- Density: Mass per volume (kg/m³, g/cm³, lb/ft³).
- Velocity: Flow velocity in pipes and ducts.
🛠️ Fluid & Thermal Properties
- Viscosity: Dynamic and kinematic viscosity in Pa·s, cP, and stokes.
- Dimensionless Numbers: Key process numbers like Reynolds, Nusselt, and Prandtl.
- Heat Flow: Total heat transfer rate (W, kW, Btu/h).
- Heat Flux: Heat transfer rate per unit area (W/m²).
- Heat Transfer Coefficient: Surface heat transfer coefficient.
- Heat of Vaporization: Energy required to vaporize a substance.
- Specific Heat: Heat required to raise temperature per unit mass.
- Thermal Conductivity: Heat conduction ability of a material.
- Thermal Resistance: Resistance to heat transfer.
⚡ Power & Miscellaneous
- Power: Energy per unit time (W, kW, hp).
- String: Utility unit for parsing and formatting symbolic/engineering values.
🌐 Why Use the Units Module?
- Reliable unit conversions across multiple engineering systems (SI, Imperial, CGS).
- Consistent integration with Process PI calculations.
- Ready-to-use engineering constants and formulas.
- Supports piping, heat transfer, and equipment design workflows.
➡️ Continue with individual unit pages for detailed usage examples and conversion tables.