FieldEngineersKitEngineering Reference & ASME Code Basis
1. Formula & conversion factors
IAPWS-IF97 Industrial Formulation for the Thermodynamic Properties of Water and Steam · ASME Steam Tables (IAPWS-IF97 basis) · IAPWS Release on the Viscosity of Ordinary Water Substance (2008)
ρ = 1 / v(T, P) [kg/m³ or lb/ft³]
Cp = (∂h/∂T)P [kJ/(kg·K) or Btu/(lb·°F)]
ν = μ / ρ · μ from IAPWS viscosity formulation
IAPWS-IF97 Region 1 liquid screening · Region 4 saturation for boiling point / phase
Field screening for compressed / subcooled liquid water using IAPWS-IF97 Region 1–aligned property bands and Region 4 saturation pressure. Viscosity and thermal conductivity use IAPWS industrial liquid correlations. Do not use for steam, two-phase, or supercritical states without a full steam-table verification.
- ρ (Density) — 1 / v(T, P) — primary hero value with C_p.
- C_p (Specific heat capacity) — Isobaric heat capacity of liquid water.
- μ (Dynamic viscosity) — IAPWS industrial liquid viscosity (Pa·s / cP).
- ν (Kinematic viscosity) — μ / ρ (m²/s or cSt).
- T, P (Temperature & pressure) — °C/°F and bar/psi state point for Region 1 liquid.
2. Quick reference lookup table
| T | P | ρ | C_p | μ | Phase note |
|---|---|---|---|---|---|
| 20 °C | 1.013 bar | 998.2 kg/m³ | 4.182 kJ/kg·K | 1.00 cP | Subcooled |
| 20 °C | 1 bar | 998.2 kg/m³ | 4.182 kJ/kg·K | 1.00 cP | Subcooled |
| 40 °C | 1 bar | 992.2 kg/m³ | 4.179 kJ/kg·K | 0.65 cP | Subcooled |
| 60 °C | 1 bar | 983.2 kg/m³ | 4.185 kJ/kg·K | 0.47 cP | Subcooled |
| 80 °C | 1 bar | 971.8 kg/m³ | 4.196 kJ/kg·K | 0.35 cP | Subcooled |
| 100 °C | 1 bar | 958.4 kg/m³ | 4.216 kJ/kg·K | 0.28 cP | Near sat. |
| 100 °C | 1.013 bar | 958.4 kg/m³ | 4.216 kJ/kg·K | 0.28 cP | Sat. liquid |
| 150 °C | 5 bar | 917.0 kg/m³ | 4.316 kJ/kg·K | 0.18 cP | Compressed |
| 200 °C | 20 bar | 864.7 kg/m³ | 4.505 kJ/kg·K | 0.13 cP | Compressed |
| 68 °F | 14.7 psi | 62.3 lb/ft³ | 1.000 Btu/lb·°F | 1.00 cP | Subcooled |
| 212 °F | 14.7 psi | 59.8 lb/ft³ | 1.007 Btu/lb·°F | 0.28 cP | Near sat. |
| 300 °F | 100 psi | 57.3 lb/ft³ | 1.03 Btu/lb·°F | 0.20 cP | Compressed |
Screening values from IAPWS-IF97 Region 1–aligned liquid polynomials. Near-saturation duties (100 °C · 1 bar) evaluate as liquid for field use — verify phase with a full steam table when P < Psat(T).
3. How to use this calculator
- 1
Select unit system
Use the navbar UnitSwitcher for metric (°C, bar) or imperial (°F, psi).
- 2
Enter temperature and pressure
Stay within 0–350 °C and 0.1–200 bar (or °F / psi equivalents) for Region 1 liquid screening.
- 3
Read ρ · C_p hero and viscosity summary
Hero shows density and specific heat; summary lists μ, ν, v, and k.
- 4
Check phase / boiling point rows
Confirm Subcooled / Compressed Liquid status. If vapor is possible, open a steam table.
4. Engineering FAQ
At 20 °C · 1.013 bar, hero density is about 998.2 kg/m³ with C_p ≈ 4.182 kJ/kg·K — the common IAPWS / ASME steam-table ambient liquid values.
No for final design. This calculator is IAPWS-IF97 Region 1 liquid screening. Steam / two-phase / supercritical states need a full steam-table evaluation.
ν = μ / ρ. Dynamic viscosity μ uses an IAPWS industrial liquid correlation; density comes from the Region 1–aligned liquid model at your T and P.
Carry temperature/pressure into pipe-wall-thickness, flange-dimension-weight, or pressure-drop-friction for piping design and Darcy friction screening.