i guess ive always been sorta a piston head! need ur help here!i understand gas 2 and 4 cycle operation! i understand 4 stroke diesel. yet 2 stroke diesel is a mystery to me! yet early steam locos operated on a system where the piston got pushed on both the top and bottom of the piston, giving it power on every cycle! would this be concidered a 1 stroke, because it powers on every stroke?
Yes, but not all of them are 1 strokes
You have to remember in the loco this was a double acting piston (not a 1 stroke) and that the power was provided from the "engine" ie the boiler...the piston is just a "motor", not the generator of the power. I worked Weirs double acting reciprocating fuel pumps for many years.
The locomotive engine that counter is describing could be called a one cycle.It makes power each direction.But it still takes two strokes of the piston to make one revolution on the crankshaft.It could also be called a two cycle with power on each stroke.Or we could call it a double acting cylinder.
Describe for us just what is a mystery to you about the 2 stroke diesel.
Here ya go, should make it a little clearer. http://www.marinediesels.info/Basics/the_2_stroke_engine_explanation.htm
But its not an engine...its only a motor...just like a hydraulic cylinder.
Its a mystery to me that I'm still sane after looking after a bunch of V53's for years...what that...speak up!
That's a good one, Squizz. But what's really a mystery; if someone asked you tomorrow to "come look at my V53"...you would! :tong
What's the difference?Is a piston in an engine much different than a hydraulic cylinder?they are both transfering energy created from pressure.A motor has rotation ,a hydraulic cylinder only has movement back and forth.It's when the cylinder's work becomes rotation through a crankshaft that we call it a motor or engine.
I don't agree with that at all and here why. The steam piston as Counter questioned in the intial post is simply a drive mechanism..it is the motor, nothing more, it converts energy into tractive effort. The steam boiler has combustion and produces the energy in the form of steam....it is thus it is the engine. Semantics aside. For Counter's single stroke engine, the cylinder would require combustion on both sides of the piston ie, it would have an injector or spark plug at either end of the piston such that it produces power on every stroke. If you put a rattle gun on the end of an air hose you don't call it an air engine do you?. Its exactly the same as the steam piston, hydraulic piston etc. In fact, in most hydraulic winch motors, the crank shaft is driven by pistons in a radial arrnagement...its still a hydraulic motor same as a cyclinder. It does not produce the energy. It converts energy into effort. The double acting steam piston to which Counter refers is actually a relatively simple motor...they have been around for over 100 years. It is not a 1 stroke engine. I do believe the Australian inventor Ralph Sarich (who sold his technology to Chrysler) experimented with a 1 stroke principal when developing his orbital engine however, I don't know where that all ended up. In a double acting reciprocating steam motor the steam is directed to either end of the cylinder through a shuttle valve called a "Glissard Valve". A pilot valve, controlled by the mechanical movement of the piston allows shooting steam to postion the Glissard for the next stroke. As I said, its been around for over 100 years and an engine it is not. Hope that helps.
25c, perhaps I can explain it better like this. Counter is trying to understand Internal Combustion Engine Theory...2 stroke, 4 stroke etc. There is no internal combustion in the steam piston, only steam being directed to one and then the other.
If I'm reading this right, the difference in question- at least as far as steam vs diesel is concerned- is internal vs external combustion. Obviously you don't want combustion of any sort in a hydraulic cylinder. LOL A couple more engine types, just to muddy the waters a bit- some big marine diesels are double-acting two strokes, with a power stroke on both the downstroke and the upstroke. Then there's something that Bruce Crower (founder of Crower Cams) has been working on- a six stroke. The first four are the same as a normal 4 stroke- intake, compression, power, exhaust- but when the piston comes up again water is injected making for a steam power stroke, then another exhaust stroke for a total of six. No cooling system is needed, and it is supposed to be phenomenally thermally efficient. I know he had a single cylinder version running a few years ago, I don't know if anything ever became of it.
A motor or engine rotates like the planet earth.A rattel gun on the end of an air hose is an engine.It's rotating under pressure like an engine or motor .You dont have to agree with it Squizzy246B,but thats the how it works.
Very well thought out presentation Squizz. :notworthy I'm still stuck on "1 stroke". When we say "stroke", aren't we generally speaking "cycles" of a piston engine? And isn't the basic definition of cycles "the number of cycles required for a piston to convert fuel into energy?" My question is; for a piston engine to convert fuel into energy, can there even be a "one stroke"? The first thing we have to have to burn the fuel to convert it to energy is...compression. That "is" one stroke. What happens after that? The piston "is" going to go down, the energy side of converting fuel into energy...another stroke. Given this, "1 stroke" doesn't seem possible on a piston engine, right? I realize we also have reciprocating and rotary engines, but can the term "stroke/cycle" even be applied to them? :beatsme I still think it's odd that counter would equate steam drive pistons to internal combustion engine strokes, I would have never thought of that one.
25c, your right, I don't have to agree and thats not how it works becuase you are crossing disciplines with common terminology. You might think thats being pedantic but its trying to say that basic engineering fundamentals of the last century are totally irrelavent. I don't want to get too far off topic I'll try and explain. In hydraulics or pneumatics the thing that does the work is the motor and it doesn't matter wether its turbine driven, reciprocating, radial piston or whatever...a rattle gun is definetly not an engine. Hydraulics machanics will tell you there is a pump and a motor. So physically it might appear similar but combustion engine principles and hydraulics/pneumatics are a different kettle of fish. They share some mechanicals. Thats exactly what I'm getting at and ATCO articulates it well. A steam driven piston ...wether you call it an engine or not, I'm not fussed really, .does not equate to the same principles of a 1 stroke combustion engine. As I said, despite the mechanical similarities, its a whole different field of thermodynamics and combustion cycle technology.
not being a mechanic i probably should not stick my nose in to this, however having said that let me say this, a rattle gun does not contain an engine, as such ,( working on the theory that an engine is an internal combustion engine ) it has a motor driven by compressed air, much like a hydraulic motor is driven by oil under pressure, or an electric motor is driven by electricity, a steam engine is better described as a steam motor driven by high pressure steam. all of the above is based on an engine being an internal combution engine powered by gasoline, diesel, gas etc..
engines motors when in trade school mainy yrs ago and I thought I had it . the engine internally driven the motors externally driven and along came that darn out board motor to make me scratch my head. thanks the BIG D
Nope. The potential enrgy of the compressed fluid either water or air is the energy source. Work was done on these fluids raising their potential energy states (heating or compression really the same things ultimately) so they in turn could do work. Now the Internal compustion engine either 2 or 4 stroke takes the potential energy from fuel ( high energy state) and burns it and produces work. Heat gasses and other by products are created (lower energy state). The difference in these concepts are say a wrecking ball. It will do nothing on flat ground because no work has been done on it to give it a higher potential energy state. Move that same wrecking ball up a slope ( Do work and raise its energy state) and it will remove houses cars and poodles with ease. I get a serious kick out of the solar energy folks saying to use more. Ultimately that is where all the energy on our little blue green ball in space comes from. (for an in depth explanation on that topic ask and I'll start a new thread) A steam engine works the piston from external power in other words the piston is only drive train. ultimately equal to a rear end or transmission depending on the train. Same with an air tool. air compressed externally is passed to the tool to buzz jabber and squeal. They use energy not re-direct energy from fuel. Back to topic: A 2 stroke engine either diesel or gas (petrol) put simply does the same things as a four stroke but in half the time ( number of strokes) A 4 stroke engine has 1: intake stroke; air and fuel are drawn into the cylinder. (beginning with piston a Top Dead Center (TDC) 2: compression stroke; as the piston returns to the top of the cylinder the fuel-air mixture is compressed and a spark (if gas) is applied ( in a diesel only compression and heat are needed (compress something and voila! heat as by-product)) 3 ower stroke: The combustng/burning mixture expand creating more heat and gasses (these are somewhate due to inefficiency but also gotta remember the Law of Conservation of Energy) 4: Exhaust Stroke: after the piston hits bottom dead center for the 2nd time and returns to TDC it pushes the exhaust gasses out and the cycle begins again. This is a simplified version of the cycle not taking into account the work of the valves but in this case they are secondary. In a greakdown of a 2 stroke the cycle looks/ reads like this. Starting from TDC after a power stroke the piston moves downwards and as it reaches BDC the exhaust is pushed out and clean air is drwn in (very inefficient as not all exhaust is removed) piston moves up again compression begins, is ignited, and piston moves down again. Hope this helps If I've made a mudle of anything let me know.
mystery of 2 stoke diesel the mystery to me about 2-stroke diesels is as follows. i understand a 2-stroke gas, and how it iliminates the oil sump crankcase and cam/valvetrain.do's 2- stroke diesel also iliminate a sump full of oil and use diesel fuel on top and bottom?
OK, let me see if I got this. Your referring to the gas engine two stroke design, such as a motorcycly engine, and how it "eliminates" the use of lubricating sump oil to lube the crankcase. Instead, it uses a "dry crankcase" with lube oil mixed with the gasoline to lubricate crankcase. Correct? And your wondering if the 2 stroke diesel does something similar, such as, a dry sump using diesel mix to lube crankcase. Is this correct?
its still outside sources puting force against a piston in a cylinder by many means. maybe it be pressure, or typical vacume draw of many! blower and turbo engines start to make this equation even more fun! old steam engines in ships would use the same shot of steam in one cylinder and re-use it 2 or 3 times in adjacent cylinders to maximize the effort! and they made gobbsss of tork doin it !
Whoa, slow down little doggie! Your taken bites out of the pie from all directions! Let's solve the "two stroke thing", then move on to blowers and turbos and their affect on engines. And to keep the discussion simple, let's leave steam out of the equation and stick with the internal combustion engine. Steam power isn't mechanically the same as internal combustion. They do the same thing, produce power, but achieve the end result in a different manner.
Counter: I'm sorry, but you can't keep comparing an Internal Combustion Engine with the likes of a Triple Expansion Steam engine in order to better understand ICE theory. A steam piston does not have combustion, it doesn't need to ingest combustion air or fuel and the cycle control mechanisms are different. You need to get past the "gas acting on the piston" thing and study some ICE theory.
differnt strokes! so true atco! i still dont understand the 2 stroke disel! help me here!
tubo/blower, is so obviously such a great source of power,in any motivation, i cant believe it hasnt moved into the automotive industry stronger! let also bikes. quads,sleds and the such! pushin fuel and air into a engine freely is just common sense!!!!!!!!!!!!
2 stroke diesel are wet sump, you do not mix oil with the oil :thumbsup, Umm you do not mix oil with the diesel in the fuel tank. They have a normal oil pump, oil filters, oil pans and normal oiling system. A lot of people associate the words 2 stroke and mixing oil with fuel for lubrication, it is not required for all 2 stroke engines and none that have a pressurised oiling system. This site will explain it further. http://auto.howstuffworks.com/diesel-two-stroke1.htm
Exactly Sqizzy! Yep.