I think it depends on if you categorise diesel engines as " heavy oil " engines. Bit of a grey area, perhaps we should call them Hornsby Ackroyd engines ?
The model aero engines I mentioned do use compression ignition. I believe so car engines use fuel injected into the manifold.
Then to confuse matters, when factories used ic engines to drive lineshafting, the price of heavy oil and gas fluctuated, which gave rise to the multi fuel engines - when heavy oil was cheap they'd run as pure heavy oil engines, when gas was cheap they'd turn the diesel right down, just enough to self ignite, and use gas for the power. There is a company that converts diesels to run on LPG.
Doesn't a hot tube use heat and compression?
The model aero engines I mentioned do use compression ignition. I believe so car engines use fuel injected into the manifold.
Then to confuse matters, when factories used ic engines to drive lineshafting, the price of heavy oil and gas fluctuated, which gave rise to the multi fuel engines - when heavy oil was cheap they'd run as pure heavy oil engines, when gas was cheap they'd turn the diesel right down, just enough to self ignite, and use gas for the power. There is a company that converts diesels to run on LPG.
Doesn't a hot tube use heat and compression?
Cummins achieved a design that uses just enough diesel fuel to ignite the gas / air injected mix, very good emissions results. Diesel engine with electronic ignition control, and the diesel use was down to about 20%, the rest of the energy came from the (lean) gas mixture, gas being fed into air intake.
Natural gas, I think.
Here trucks are being converted from diesel to natural gas, because of emission requirements and fuel cost, but most seem to be using a totally new head with spark ignition, and lower compression. Basically same block with new head.
My 800 cc car goes about 20 km on petrol, about 95 Rupees, and about 27 km on a kilo of natural gas, about 80 Rupees.
Older prices were 54 Rupees or so for gas, and 72 for petrol...
The biggest expense for trucks are fuel, and tires, so at least for short range work, trucks are going for gas as fuel.
Older trucks have to be scrapped, newer ones to be purchased, then the economics have to be considered.
Some cities have banned diesel, so the truck has to be gas if the load is for that city.
Natural gas, I think.
Here trucks are being converted from diesel to natural gas, because of emission requirements and fuel cost, but most seem to be using a totally new head with spark ignition, and lower compression. Basically same block with new head.
My 800 cc car goes about 20 km on petrol, about 95 Rupees, and about 27 km on a kilo of natural gas, about 80 Rupees.
Older prices were 54 Rupees or so for gas, and 72 for petrol...
The biggest expense for trucks are fuel, and tires, so at least for short range work, trucks are going for gas as fuel.
Older trucks have to be scrapped, newer ones to be purchased, then the economics have to be considered.
Some cities have banned diesel, so the truck has to be gas if the load is for that city.
Oh, I forgot...
We had a truck for the Army, called Shaktiman, it was licensed from MAN, Germany, 1960s design.
The engine was multi fuel, and the secret was the special piston crown, the fuel was allowed to evaporate off the piston and burn.
Reputedly ran on cooking oil if needed, quietest diesel I have seen.
Sadly, about 20 years out of production.
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjb3-i275L4AhVL1zgGHV2nAP0QFnoECEIQAQ&url=https://en.wikipedia.org/wiki/M-System&usg=AOvVaw1_2-e2OBkxKWt0zPpVNAXU
The image may not be accurate, seems hard to find on the net.
Basically a chamber inside the piston, the description is there on Wikipedia.
We had a truck for the Army, called Shaktiman, it was licensed from MAN, Germany, 1960s design.
The engine was multi fuel, and the secret was the special piston crown, the fuel was allowed to evaporate off the piston and burn.
Reputedly ran on cooking oil if needed, quietest diesel I have seen.
Sadly, about 20 years out of production.
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjb3-i275L4AhVL1zgGHV2nAP0QFnoECEIQAQ&url=https://en.wikipedia.org/wiki/M-System&usg=AOvVaw1_2-e2OBkxKWt0zPpVNAXU
The image may not be accurate, seems hard to find on the net.
Basically a chamber inside the piston, the description is there on Wikipedia.
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I think there are tanks that are mulit fuel, someone bought one and gets fuel for free because the RAC ( roadside mechanics ) have no other way of disposing of diesel mixed with petrol ( gasoline ). If we all ran Stirling engines we could run them on anything ( including presumably hydrogen ) and they're external combustion engines there's less harmful emissions.
Bit inconvenient, driving a tank around town.
No punctures or tire issues...
No backchat from other drivers...or back seat drivers either.
No punctures or tire issues...
No backchat from other drivers...or back seat drivers either.
Not every engine that runs on diesel is necessarily a Diesel engine.
Hot bulb engines for example run on diesel or any other oil but they are not Diesel engines since they have very low compression (3:1 - 5:1) and ignition occurs because of the hot bulb they are named after.
Equally Diesel engines do not need to run on diesel either. Rudolf Diesel's first prototypes for example ran on coal dust. When somebody mentioned that coal dust is hard to come by in central Africa he changed to peanut oil. They do use compression ignition and therefore a high compression ratio of 16:1 to 25:1 and inject fuel at very high pressure.
If I understand it correctly it is the compression ignition which gives them their efficiency advantage over the Otto cycle (named after their inventor Nickolaus Otto) 4 stroke petrol engines which rely on a spark plug for ignition. In terms of compression they are in between Hot Bulb engines and Diesel ones.
Here is a stationary Hot Bulb engine in action: Huge Hot Bulb Engine Blues!! Old school drum machine with 1930's Dobro & mandolin. - YouTube
there are several interesting engine shapes, stirling is one of them, but also Pantone.
The big problem with these engines is that their speed is very hard to vary without loss of performance, so you have to add a CVT type transmission to hope to transmit the effort in an optimum and efficient way.
these two engines are very interesting in very different fields, I have a preference for Pantone which works with a mixture of water and any hydrocarbon chain.
on the other hand, for me, a direct fuel injection in a modern engine with antipollution standards is an aberration.
reinjecting oil vapors into an air intake pipe without the pipe being "rinsed" with fuel creates a carbon deposit which after a while comes off at the ends and goes straight into the d valves admission, not to mention the problems of ignition and injection management due to the required performance which most often results in a pierced piston or the destruction of valves.
The big problem with these engines is that their speed is very hard to vary without loss of performance, so you have to add a CVT type transmission to hope to transmit the effort in an optimum and efficient way.
these two engines are very interesting in very different fields, I have a preference for Pantone which works with a mixture of water and any hydrocarbon chain.
on the other hand, for me, a direct fuel injection in a modern engine with antipollution standards is an aberration.
reinjecting oil vapors into an air intake pipe without the pipe being "rinsed" with fuel creates a carbon deposit which after a while comes off at the ends and goes straight into the d valves admission, not to mention the problems of ignition and injection management due to the required performance which most often results in a pierced piston or the destruction of valves.
Not sure what you mean by this.
Direct injection means the fuel is injected directly into the combustion chamber, not into the manifold (Air intake pipe) or pre-chamber.
I never said that .
direct injection = direct injection.
but the air must enter through an air intake pipe, right?
the problem today is the rejection of oil vapors in the air intake pipe, air intake pipe which does NOT see fuel and since it does NOT see fuel, the deposits of carbon accumulate in the air intake pipe until the pieces start to come off and you can imagine the rest ....
is it clearer there ?
I do not know if you have broached the subject of the old generation of direct petrol injection (I have not read everything) but we must not forget that at the time petrol contained lead, lead which ensured partly the lubrication of the pump.
direct injection = direct injection.
but the air must enter through an air intake pipe, right?
the problem today is the rejection of oil vapors in the air intake pipe, air intake pipe which does NOT see fuel and since it does NOT see fuel, the deposits of carbon accumulate in the air intake pipe until the pieces start to come off and you can imagine the rest ....
is it clearer there ?
I do not know if you have broached the subject of the old generation of direct petrol injection (I have not read everything) but we must not forget that at the time petrol contained lead, lead which ensured partly the lubrication of the pump.
That is why I quoted your post. You literally said that oil vapors are 'reinjected' into an air intake pipe ie a pipe which only sees air coming into it in a direct injection system. I do not understand where the oil vapors are supposed to come from.
Lead in petrol reduced valve wear, it had very little to do with the pump ie if you have a petrol engine which is not suitable for use with unleaded petrol you need to give it hardened valve seats but the fuel pump and or injection pump can remain the same.
The only engine which ever pierced a piston on me was a VW Beetle with a carburator. Nowadays fuel injection is used universally because carburator engines cannot fulfill pollution standards anymore.
Lead in petrol reduced valve wear, it had very little to do with the pump ie if you have a petrol engine which is not suitable for use with unleaded petrol you need to give it hardened valve seats but the fuel pump and or injection pump can remain the same.
The only engine which ever pierced a piston on me was a VW Beetle with a carburator. Nowadays fuel injection is used universally because carburator engines cannot fulfill pollution standards anymore.
Lead (tetra ethyl lead) was added as an anti knocking agent and octane booster (?)
Other agents are used now, in fear of lead poisoning.
Other agents are used now, in fear of lead poisoning.
And IME were are far the better for it! Not just the pollution, but also how well cars run these days. I drove carbureted cars and motorcycles well into the 21 century and am very happy to leave them behind. Carburetors, yuck! Now that we have electronic injection systems there will be no going back to mechanical for gasoline, but I'm surprised at how well it worked on the LADA with just a semi-kludged set up.
I had to tell the kids that my mom would sometimes make us be quiet when she started the 1975 Volkswagen van. You had to listen carefully and pump the gas at just the right time.
I drove something carbureted up until about 1995 and remember the odd things you did to keep the engine happy.
Having a fuel injector per cylinder these days means the computer can tell in a spark plug fouls and will stave it of fuel for a few cycles.
He considered coal in his book. Prototypes ran petrol and similar for convenience.
The US railroads "burned" coal in Diesels for a very short time while passing through West Virginia. The rise of Diesel locomotives threatened WVa's economy. The state mandated use of coal. Much work was done with pulverized coal in oil in Diesel engines. But the idea collapsed of its own ridiculousness.
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Coal is abrasive, slurry pipelines need special pumps.
Using it in an engine is.... well it went out of use fast...
As an aside, all the three ships of the Titanic class did not last 10 years, the Titanic sank because the marketing people wanted it to set a record for fastest Atlantic crossing on her maiden voyage, so she took a shorter route....and collided with an iceberg.
A sister ship sank because of a coal dust explosion, in WW1.
The third, you can look it up...
Using it in an engine is.... well it went out of use fast...
As an aside, all the three ships of the Titanic class did not last 10 years, the Titanic sank because the marketing people wanted it to set a record for fastest Atlantic crossing on her maiden voyage, so she took a shorter route....and collided with an iceberg.
A sister ship sank because of a coal dust explosion, in WW1.
The third, you can look it up...
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if you don't understand what you call the "blow by" and the way it is managed today, you don't understand how an engine works, or maybe on paper or on internet documents.
ditto for the piston drilling with direct injection and the problems of electronic management, that's why there are now knock sensors (I don't know the name in English but I can explain) because the engines Modern models have such a diagram of operation to obtain this performance that at the slightest failure of a control element (such as one of the lambda probes or a knock sensor) and it is guaranteed engine failure. Also try with "AFR management" if you want to learn.
Here's a bit of an old document on how VW handled it with the TFSI, but it's evolved again now.
https://www.forum-audi.com/topic-180-audi-tt-rs-mk2-moteur-25l-tfsi-5-cylindres.html
ditto here with peugeot
https://exxotest.com/wp-content/uploads/2018/03/GU_MT-MOTEUR-E3CT_FR.pdf
And again, we have not addressed the problem with the "long life" lubrication programs 🙄
Blow by is the air from the block forced down by pistons going downwards, and that is vented into the air intake on some engines.
Though this is compensated for the most part by other pistons going upwards.
Also refers to leaks past the piston rings.
Oil does char/blacken if expose to heat for a long time.
Dirty or oily air in the air intakes...source of problem...
Though this is compensated for the most part by other pistons going upwards.
Also refers to leaks past the piston rings.
Oil does char/blacken if expose to heat for a long time.
Dirty or oily air in the air intakes...source of problem...
Blow by is when you have damaged piston rings and the piston allows pressure to go past it into the block.
An extreme version happened with aforementioned Beetle which fired the oil filler cap off with such force it dented the rear hood from the inside.
If your intake air contains oil you have serious problems elsewhere, try changing the air filter. Intake valves should no coke up.
The only engine I ever opened up far enough was an Audi 1.9 TD with 120 000miles on it. The intake valves looked like new. The exhaust valves not so much.
An extreme version happened with aforementioned Beetle which fired the oil filler cap off with such force it dented the rear hood from the inside.
If your intake air contains oil you have serious problems elsewhere, try changing the air filter. Intake valves should no coke up.
The only engine I ever opened up far enough was an Audi 1.9 TD with 120 000miles on it. The intake valves looked like new. The exhaust valves not so much.
Oil in the air intake usually mean bad PCV.
I had a VW that would actually pull engine oil from the PCV if you drove it over 5000 rpm around a corner... So I corked the PCV system.
I had a VW that would actually pull engine oil from the PCV if you drove it over 5000 rpm around a corner... So I corked the PCV system.