Steam Table Calculator

In this Steam Table Calculator, we will show you how to calculate different steam properties in just a few clicks.

We will also help you understand the steam table formula, its terms, and how it connects pressure, volume, and temperature.

How do you use it to find pressure or temperature?

Where is this formula used in real life?

Find all the answers right here! We’ll also walk you through a step-by-step example so you can see exactly how steam property calculations work in practice.

Steam Table Calculator (PV = nRT)

Select variable to calculate:

Pressure (P) in Pa:

Volume (V) in m³:

Number of Moles (n):

Temperature (T) in Kelvin:

Specific Gas Constant for Water (R):

Detailed Formula Explanation

The ideal gas equation for steam is represented as:

PV = nR_uT or P v = R_specT

(Use the first when working in moles, and the second when using specific volume per kg.)

Absolute Pressure — measured in Pascal (Pa).

Total Volume of the system — in m³.

Number of moles — in mol, used with the universal gas constant.

Specific Volume — volume per kilogram, m³/kg.

R_spec

Specific Gas Constant for Water ≈ 461.5 J/kg·K.

R_u

Universal Gas Constant ≈ 8.314 J/mol·K.

Absolute Temperature — in Kelvin (K). (T = °C + 273.15)

Relation between R_spec and R_u:
R_spec = R_u / M, where M = molar mass of water (0.018015 kg/mol).
→ 8.314 / 0.018015 ≈ 461.5 J/kg·K.

Real-world Applications

Steam Turbine Design

Estimate steam density (via specific volume) and mass flow to size blades and compute turbine power using thermodynamic states.

Boiler and HVAC Calculations

Compute mass of steam or required heat input knowing pressure, temperature and volume — helps size boilers & heat exchangers.

Process Safety & Relief Sizing

Use the ideal-gas relation to estimate vapor mass in vessels at given P & T for relief valve sizing and safety analysis.

Gas Flow & Instrumentation

Convert measured pressure & temperature to density or specific volume for flowmeter calibration and mass-flow computations.

Stepwise Solution

Problem Statement (Narrative): A rigid container of volume V = 0.05 m³ holds steam at absolute pressure P = 200 kPa and temperature T = 450 K.
Using the specific form P v = R_spec T (R_spec = 461.5 J/kg·K), find:

1 : Specific volume v (m³/kg)
2 : Mass of steam m (kg)
3 : Number of moles n (mol) — cross-check with the molar PV = n R_u T form

Step 1 — Compute Specific Volume (v):
v = (R_spec × T) / P
v = (461.5 × 450) / 200000 = 1.038375 m³/kg
So v ≈ 1.0384 m³/kg.
Step 2 — Compute Mass of Steam (m):
m = V / v
m = 0.05 / 1.038375 = 0.04815216 kg
So m ≈ 0.04815 kg (≈ 48.15 g).
Step 3 — Compute Number of Moles (n):
n = (P × V) / (R_u × T)
n = (200000 × 0.05) / (8.314462618 × 450) ≈ 2.67272 mol

Steam Property Reference Table

This reference table provides common values for water and steam at different temperatures and pressures. Use it to verify your calculated results or understand the typical behavior of steam.

Temperature (°C)	Pressure (kPa)	Specific Volume (m³/kg)	Specific Enthalpy (kJ/kg)	Specific Entropy (kJ/kg·K)
100	101.3	1.673	2676	7.355
150	475.8	0.3928	2696	7.116
200	1554.9	0.1274	2706	6.878
250	3979.9	0.0511	2725	6.639
300	8574.6	0.0217	2744	6.402
350	16529.9	0.0101	2763	6.164
400	29418.0	0.0054	2782	5.926

Note: Values are approximate and can vary slightly with pressure and saturation conditions. For precise engineering calculations, refer to detailed thermodynamic steam tables.

FAQs

1. What is a Steam Table Calculator?

In this Steam Table Calculator, we will show you how to find steam properties like pressure, temperature, or volume in a matter of seconds. We’ll also explain how the formula PV = nRT works while we’re at it.

2. What is the difference between specific volume and total volume?

Specific volume tells you how much space 1 kg of steam takes. Total volume is the space the whole steam sample occupies. Both are connected, but each is used in a different way in the formula.

3. Can I use this calculator for any gas?

This calculator is made for steam, but the same formula works for other gases too. You just need to use the correct gas constant R for the gas you’re working with.