In general, there are generally two types of engines: diesel engines and gasoline engines. The classification is made based on the fuel used for the engines, since the construction, functionality and characteristics of the engines vary according to the type of fuel to be used. These motors can be found in cars, airplanes, and even commercial generators. Therefore, it would be worthwhile to spend some time and take a look at the reason behind the preference of one type of motor over the other.
Requirements
To have a deep understanding of the topic of this article, it would help to have a passion for things under the hood. But in any case, the material has been represented in such a way that a person with little or no knowledge of mechanical engineering will also be able to follow it; a little physics in your middle or high school will suffice. To begin with, let us try to understand the working principle of the two types of motors, so that we can infer the reason behind the popularity of one type over the other.
Operating principle of diesel engines.
A diesel engine is generally known as a CI (compression ignition) engine. In a diesel engine, pistons compress air inside a closed chamber through a process called adiabatic compression. Due to the strong compression, the air temperature rises to very high levels inside the chamber. Once the sufficient temperature is reached, the fuel, which in this case is diesel, is slowly injected into the chamber in a controlled manner.
When flammable fuel comes into contact with hot air, it begins to burn. The gas produced by combustion pushes the piston down, which in turn produces the required torque. Due to its construction features, it has very little fuel residue and also excess heat is easily dissipated, making the engine well suited for long hours of maintenance-free operation under heavy loads. Among all types of internal combustion engines, diesel engines have the highest efficiency rate, sometimes more than 50%.
Principle of operation of gasoline engines
Gasoline engines, on the other hand, are internal combustion engines with a completely different principle of operation. Inside a gasoline engine, fuel and air are mixed in a chamber and gradually compressed. In addition, a spark plug is used to provide the necessary ignition point for the mixture, so that the entire process is fast and constant. Due to the presence of the spark plug, gasoline engines are widely used in cold countries where the ambient temperature is very low and it is very difficult to maintain the temperature of the mixture suitable for combustion only by compression.
In addition, the speed of the gasoline engines is higher and its parts are lighter than those of its diesel counterparts, making it the ideal choice for quick accelerations and high-speed maneuvers. However, the compression ratio of the air-fuel mixture is quite low for a gasoline engine and results in lower efficiency of gasoline engines compared to diesel engines.
Which is the best option?
Well, it depends on the nature of the use. Experts recommend gasoline engines for cases that require very high speed and high acceleration. Also, historically diesel engines are noisier than gasoline engines and people associate this with the unpleasant fumes coming out of the exhaust. But the fact is that the carbon dioxide emission of gasoline engines is higher than that of diesel engines.
Diesel engines are a better option due to many factors such as:
- The cost of diesel is lower than that of gasoline in most countries of the world.
- Diesel engines last longer due to their robust construction.
- Efficiency and maintenance cost are a big deciding factor for the choice.
- At low speeds, diesel engines can generate very high power. This is the ideal case for commercial and industrial applications.
For all of these reasons, machines using diesel engines have also been observed to garner higher resale values. Surveys have proven the fact that used diesel cars and used diesel generators generate more inquiries when they are prepared for resale. However, it is highly recommended that you consult a domain expert to determine which engine to purchase for your needs.