Diesel and Gasoline Engines
Both being internal combustion type diesel and gasoline engines can be considered as similar. Simply, both engines converts chemical energy into mechanical one by burning fuel. In combustion engines the combustion (explosion of fuel) occurs at combustion chamber with , generally, help of oxidizer (air, another fluid, etc. ). The output, high heat and pressure of the burning process is transfered to other components of the engines which expose pressure as a mechanical energy. Some of these parts can be examplified as turbines, nozzles, pistons (Britannica, 2012).
These two types of engines basically differs in the way of burning the fuel and production of chemical energy. First, gasoline engines will be introduced in general aspects. 2. 1. Gasoline Engines Both of the engines oxides fuel and burns it in a chamber. The obtained pressure, and therefore, force is used to reveal dynamic action. In a ordinary gasoline engine carburetor, is the first member that mixes air (oxidizer) and fuel in a required proportion. In gasoline engine mixture is injected in to chamber by fuel injector.
Nowadays these electronic devices determines the amount and proportion of the mixture due to some parameters like; machine speed, outdoor temperature, etc. In conventional gasoline engine fuel was injected from multipile gaps into cylinder port, consequently a decrease might occur in the effectiveness of explosion. But in modern ones, the fuel is injected directly into cylinder combustion chamber. This type of gasoline engines called as “Gasoline Direct Injection Engines”. Inside the chamber (cylinder) spark plug ignites the mixture.
The revealed pressure pushes the piston toward crankshaft which alters lineer oscillation of piston into the rotary motion. 2. 2. Diesel Engines The working principle of diesel engine is same with gasoline one. The production of mechanical energy relies on same idea that includes burning of fuel and producing force to push pistons. However, the burning process is the key term that differs for each engine types. In diesel engine the explosion is not triggered by sparks but it is made with the help of compressed-hot air. On the otherhand, a mixture of fuel and oil is not injected into chamber.
The oil is put into chamber after hot-high tempered air had prepared. Therefore, a relation between air and oil can be formed in a moleculer or a little higher size particle level. Hewing (2010) defines modern diesel engines that they usually consist a turbocharger which improves the efficiency of the machine and consequently increases the power output. The major differentiation in the structure and working scheme of diesel and gasoline engines is their fuel usage style.
As mentioned previously, Gasoline engines prepare an air-oil mixture and ignites it with spark plugs to produce power. On the other hand, diesel engine uses hot and presurrized air to start burning therefore, injection of both air and oil into the chamber are made seperately. The mixing is expected to happen during burning process. Diesel engine is always louder due to the uneven (it is a routine) mixture of oil and air moreover, due to the usage of hot air to ignite fuel. Due to this system a longer period of burning process which produces higher noises occurs.
On the other hand, during cold seasons the vibration and noise made by diesel engines increases. Generally, gasoline engines do not use all of the fuel (incomplete combustion) that taken into chamber. Therefore, noxious substance and smoke accumulation is much more common for gasoline engine compared to diesel engine. 3. 1 Efficiency In diesel engines the produced heat is much higher after burning of oil. Mainly, higher compression ratio inside the cylinder causes high heating therefore both of higher pressurre and temperature rates make diesel much more effective than gasoline engine.
Moreover, direct fuel injection causes a more appropriate mixing in the cylinder camber therefore, the contact rate between fuel and hot air is increased. 3. 2Fuel Economy and Costs Why diesel maintenance cost have less parts than gasoline will be fully explained. The diesel engine has a more simplistic scheme because it has much more simple burning system therefore the engine part cost much more cheap to be repared or cleaned. Furthermore, the density of fuel is much higher in diesel compared to gasoline, hence the fuel economy in the level of 20 – 30% is reached by the usage of diesel oinstead of gasoline (S.
This means that it takes more gasoline to equal the power output of diesel. 3. 3Power and Torque In diesel engines the amount of heat produced is much more higher but the force and presurre obtained from the gasoline-air mixture is comparetively higher, gasoline engines forms much more higher amounts of horse power. However, the piston oscillation of diesel engines are higher therefore, more torque can be produced by diesel engines. The torque difference of diesels is perfectly suited for pulling heavy loads up steep grades.
Then, gasoline engines will be discussed about how preferable to truck and transport. Gasoline engine produces much more horsepower which gives vechiles ability to accelerate in higher values. Higher torque means working of machine in higher frequencies which means least deformation and longer duration. Therefore, diesel engines work in higher frequencies but has higher endurance. On the other hand, higher torque production capacity makes diesel engines valid for large vechiles that also works in steep iclinations. For public transportation diesel torque is also required.