Saturday, March 19, 2011

continued engine basics

continuing off my last post, i am just going to put in a quick word about diesel engines and carburetors here.

what is unique about diesel engines is there lack of spark plugs, and improved efficiency, and power.

the idea around a diesel engine, is instead of using spark to ignite the fuel, you use pure compression to ignite the fuel. These engines run with a much higher compression in the pistons, and this combined with the different type of fuel allows for the fuel to be squeezed so much that it ignites. the more pressure on an explosion the more power you get from it, and the more power you get from it, the more compression on the next explosion.

with the logic of this design, this engine becomes extremely efficient, and simple to understand.
as you can see from this, there is no need for a spark plug.

as you can also see from this, not every time the piston goes up it burns fuel. in order for a 4 stroke engine to work properly, it ignites fuel, gets the benefits from the explosion, and goes back up to push it out the exaust. after it pushes everything out of the exaust, more fuel and air is added as it goes back down, and when it returns up, thats when another ignition of gas will happen.

with engines with multiple cylinders, while one piston is firing, another is pushing exaust. this is the firing order.

what controls what gives the engines the fuel it needs when it needs it?

the answer is simple. a carburetor. depending on throttle input, decides how much fuel the carb gives to the engine. as you push it harder, a vent for air opens up, along with a valve for fuel. over time these get dirty, and need to be cleaned.

modern engines use fuel injectors to give fuel to the engines. these are run typically by computers, and are far more efficient.

comment with what you want to learn next!

Engine basics

Generally there are many different types of engines available for cars to have equipped. These vary by design of the layout (inline, straight, V, rotary ect.) how it gathers its power (pistons, 2-stroke, 4-stroke, rotary ect.) how many sources of power (typically number of cylinders), and how complex the components are.

for starters, lets say how the idea of a combustion engine started.. Way back in the late 19th century (not sure exact time frame) some really smart person realized that the more pressure upon something that is exploding, the larger the force of the explosion. this sparked the desire to be able to harness this information..many designs later, the piston engine was designed. see picture below.

to make an explosion with something by use of fire, you need fuel (gas) air, and spark. your car's intake takes care of the air, the gas station (your empty wallet :( ) takes care of the fuel, and the spark plug takes care of the spark.
as the piston applies pressure to the mixture that enters the combustion chamber, the force of the ignition increases. as the piston is reaching the maximum pressure, the spark plug adds spark and ignites the fuel, giving force to the piston spinning the engine.

the more pistons that do this job, the more power the engine has. this is where you hear the terms V6 vs V8, or inline 4 vs inline 6. this is how the pistons are laid out to maximize the efficiency and design. in a V- engine, the pistons are in the shape of a V.

above is a V6 engine, is it in the V shape, and has 6 cylinders, and pistons.

the types of engines goes on and on, but interesting other types include rotary, or boxer engines.

this is not piston related, but another way to get power from gasoline.


this uses pistons, but in a very different layout.

all of these in turn use the explosion to turn a crankshaft (in above picture its the green rod they are all connected to in the center), that turns the flywheel..we will get to this eventually.

this is the basic concept of a gas, combustion engine. Diesel engines do not need spark plugs, and i think i will make my next post on those.

comment with interest!

all about cars

Hey guys, ever wonder the specifics about stuff on a car? well i happen to know the answers. As someone with a strong intrest in racing, i figured id share my years of research with you guys in a simply put, one stop information center!

What do you want to learn about first? i wast thinking about starting with how a typical engine works!
comment with suggestions.