1. Displacement Volume:
- Determine the engine's displacement volume, which represents the total volume swept by all pistons during one complete combustion cycle (from bottom dead center to top dead center).
- It can be calculated using the following formula:
Displacement Volume (Vd) = (Bore Area)*(Stroke)*(Number of Cylinders)
2. Actual Intake Air Volume:
- Measure or estimate the actual volume of air inducted into the engine during one intake stroke. In most cases, we use a dedicated measurement device for accurate results. It's also influenced by engine speed, intake system design, and other factors.
3. Calculate Volumetric Efficiency:
- Once you have determined the displacement volume (Vd) and the actual intake air volume (Va), you can calculate the volumetric efficiency (VE) using the following formula:
Volumetric Efficiency (VE) = (Actual Intake Air Volume (Va))/(Displacement Volume (Vd))
The result obtained represents the volumetric efficiency of the diesel engine, expressed as a percentage. Theoretically, it should be as close as possible to 100% for optimal engine performance, but in practical scenarios, it's usually lower due to various factors such as engine design, valve timing, flow restrictions, and temperature effects.
By calculating volumetric efficiency, engineers and designers can evaluate the engine's breathing capability and make necessary adjustments to improve its overall efficiency and performance. Higher volumetric efficiency typically leads to better fuel economy, reduced emissions, and enhanced engine power output.
