Diiselmootorit

Diiselmootorit, or diesel engines, are internal combustion engines that use compression ignition to burn fuel. In a typical cycle, air is drawn into the cylinder and compressed to a high temperature. Fuel is then injected directly into the hot air, where it ignites without a separate spark. Diesel engines generally operate at higher compression ratios and are designed for high thermal efficiency and strong torque at low to moderate speeds.

Most diesel engines are four-stroke, though two-stroke designs exist in some marine and stationary applications. They come in various configurations, such as inline or V-cylinder layouts, and can be naturally aspirated or turbocharged. Modern systems use sophisticated fuel injection, including indirect injection, direct injection, and common-rail technology, often combined with turbocharging and intercooling to boost power and efficiency.

Diesel engines are known for fuel efficiency and durability, delivering high torque, which makes them well suited for heavy vehicles, industrial machines, ships, and power generators. They tend to be heavier and noisier than comparable gasoline engines and require robust lubrication and fuel systems. Maintenance can be critical, as precision in injection timing and fuel filtration affects performance and longevity.

Emissions from diesel engines include nitrogen oxides and particulate matter. Aftertreatment options such as diesel particulate filters (DPF), selective catalytic reduction (SCR) with urea, and exhaust gas recirculation (EGR) are commonly used to meet environmental standards. Ongoing developments focus on reducing emissions, improving efficiency, and integrating with hybrid or electric power systems.

The diesel engine was developed in the late 19th century after Rudolf Diesel's work and became widely adopted in transportation, industry, and power generation. Today, diiselmootorit remain a cornerstone of heavy-duty propulsion and stationary power, while continually evolving to meet stricter emission and efficiency requirements.