Skip to main content
Speclore

Sae Grade Oil

Reference data and engineering information about sae grade oil for combustion applications.

saegradeoil

Overview

Engineering reference data for Sae Grade Oil in combustion engineering.

Key Formulas

Heat Release

Q=m˙HVQ = \dot{m} \cdot HV

Fuel energy release rate.

Air-Fuel Ratio

AF=mairmfuelAF = \frac{m_{air}}{m_{fuel}}

Mass of air per mass of fuel.

Excess Air

EA=O221O2×100%EA = \frac{O_2}{21 - O_2} \times 100\%

From flue gas oxygen measurement.

Variables

SymbolDescriptionUnit
QQHeat release rateW
m˙\dot{m}Mass flow ratekg/s
HVHVHeating valueJ/kg
AFAFAir-fuel ratio

SAE Multigrade Oil Properties

4 rows
Common SAE multigrade engine oil viscosities and densities at specified temperatures.
SAE Grade(-)
Viscosity @ 40°C(cSt)
Viscosity @ 100°C(cSt)
Viscosity @ 104°F(µreyn)
Viscosity @ 212°F(µreyn)
Density(kg/m³)
Density(lb/in³)
5W-3064118.218600.0311
10W-3069118.81.18650.0312
10W-409414.311.91.58650.0312
20W-5016618.721.32.78720.0315

Source: engineeringtoolbox.com

Key Definitions

  • SAE Multigrade Oil: An oil that meets the viscosity requirements of multiple SAE grades across a range of temperatures, indicated by a dual rating (e.g., 10W-40). The "W" stands for Winter.
  • Viscosity (cSt or Centistokes): A measure of a fluid's resistance to flow. Kinematic viscosity (ν) is the ratio of dynamic viscosity (μ) to density (ρ), commonly expressed in centistokes (1 cSt = 10⁻⁶ m²/s).
  • Dynamic Viscosity (Reyn): A measure of internal fluid friction. The reyn (1 µreyn = 10⁻⁶ lb·s/in²) is a unit used in imperial engineering contexts.

Interactive Charts

Dynamic, Absolute, and Kinematic Viscosity – Definitions & Conversions

References