PetroCal is a dedicated engineering utility designed for professionals, students, and technicians working in thermodynamics, fluid mechanics, and heat transfer. The app works fully offline, allowing you to perform calculations and conversions in remote field locations.

Core Features:

1. Engineering Unit Converter
• Convert Pressure units: Pascal (Pa), Kilopascal (kPa), Megapascal (MPa), Bar, PSI, Standard Atmosphere (atm), and Kilogram-force per square centimeter (kgf/cm²).
• Convert Volumetric Flow Rate units: Cubic Meters per Hour (m³/h), Cubic Meters per Second (m³/s), Liters per Minute (L/min), Gallons per Minute (gpm), and Barrels per Day (bbl/d).
• Convert Density units: Kilograms per Cubic Meter (kg/m³), Grams per Cubic Centimeter (g/cm³), Pounds per Cubic Foot (lb/ft³), and API Gravity (°API).
• Convert Temperature units: Celsius (°C), Fahrenheit (°F), Kelvin (K), and Rankine (°R).
• Swap unit directions instantly and bookmark frequent conversion pairs.

2. Comprehensive Formula Library & Calculators
• Thermodynamics: Calculate Ideal Gas Density or approximate gas compressibility Z-Factor.
• Fluid Mechanics: Compute Reynolds Number to check flow regime, Darcy-Weisbach friction pressure drop, or Orifice Flow Rate.
• Heat Transfer: Compute Fourier conduction heat rate, Log Mean Temperature Difference (LMTD), and sensible heat duty.
• Input custom parameters and receive immediate outputs based on standard engineering formulas.

3. Engineering Constants Reference
• View universal physical and chemical constants directly on the home dashboard, including the Universal Gas Constant (R), standard gravity (g), water density references, and Stefan-Boltzmann constant.

4. Calculations & Conversions Logger
• Log calculation results and conversion parameters to a local history list for auditing and reference.

5. Field Notepad
• Create, edit, and manage text notes to document field measurements, formula observations, or task lists.
• Search notes by keywords to find logged information quickly.