WHY DIESEL ENGINES ARE MORE EFFICIENT THAN PETROL ENGINE

WHY DIESEL ENGINES ARE MORE EFFICIENT THAN PETROL ENGINE 

You know that diesel engine is the most appropriate choice of the engineers when it comes to drive heavy automobile like trucks, aircraft, ships etc. But what makes it so torque, is it the engine design, working cycle or something else. We will look towards a deep analysis to answering these questions.

Following are the reasonable points that conclude the high torque and efficiency of diesel engine.

• Diesel engine uses simple mechanism for combustion unlike in gasoline engine. Removal of ignition system not only makes the mechanism simpler but also reduces the risk of improper combustion due to damage in ignition system. In short burning of the fuel is easy and always accessible. This results in higher efficiency diesel engine.

• Diesel fuel is a heavier hydrocarbon in which carbon and hydrogen are strongly bonded with each other. And when energy is supplied in form of heat it gets explode releasing much higher energy then gasoline. In short diesel fuel has higher energy density then gasoline which results in huge explosion.

• One more factor for higher efficiency in diesel engine is its property of lubrication. Although all fuel has property of lubrication but diesel fuel has much higher lubrication then gasoline fuel.

• The compression ratio is much higher in diesel as compared to gasoline because in diesel engine air is alone compressed inside the cylinder and it’s a known fact that gas easily compresses then liquid. This is not so in gasoline engine because air-fuel mixture is compressed inside the cylinder. This higher compression gives higher heat and simultaneously higher torque.

• We can’t use Carnot cycle to get 100% efficiency but can use its principle to attain maximize efficiency. In diesel engine heat is added at constant pressure which results in higher utilization of heat energy to get maximize work output.

These were the advantageous features of diesel engine but it has some demerits as well like it releases highly toxic gases, noisy, higher maintenance cost and starting problem (now starting problem is eliminated by using a bulb nearby to the cylinder) to heat the engine before ignition. And it is costlierthan gasoline engine but with optimum operation and good maintenance resolve all these problems.