1. What is CNG Density Calculator?

Definition: This calculator estimates the density of compressed natural gas (CNG) based on pressure, temperature, and molar mass using the ideal gas law.

Purpose: It helps engineers and technicians determine CNG density for storage, transportation, and energy calculations.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \rho \) — Density of CNG (kg/m³)
• \( P \) — Pressure (Pa)
• \( M \) — Molar mass of natural gas (~0.016 kg/mol)
• \( R \) — Universal gas constant (8.314 J/(mol·K))
• \( T \) — Temperature (Kelvin)

Explanation: The formula is derived from the ideal gas law, showing how gas density increases with pressure and decreases with temperature.

3. Importance of CNG Density Calculation

Details: Accurate density calculations are crucial for determining storage requirements, energy content, and safe operating conditions in CNG applications.

4. Using the Calculator

Tips: Enter pressure in bar (default 200), temperature in Kelvin (default 293.15K = 20°C), and molar mass (default 0.016 kg/mol for methane). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is temperature in Kelvin?
A: The ideal gas law requires absolute temperature. Kelvin = Celsius + 273.15.

Q2: What's typical CNG pressure?
A: CNG is typically stored at 200-250 bar (2000-2500 psi) in vehicle tanks.

Q3: How accurate is this calculation?
A: It's based on ideal gas law; real CNG may deviate slightly due to non-ideal behavior at high pressures.

Q4: What's the molar mass of natural gas?
A: Typically ~0.016 kg/mol (16 g/mol) for methane, the main component of natural gas.

Q5: How does temperature affect CNG density?
A: Density decreases as temperature increases at constant pressure (Charles' Law).