zoom44

excellent and hello

Umbra

Exactly, it makes no sense at all. We are all concerned about detonation in our rotaries and someone thinks it's a good idea to make it work that way completely? I don't. Diesels are dirty and produce tons of particulates, not a good solution at all.

Ultimately the only options here are nuclear or increasing efficiency on fossil fuel sources. Hydrogen doesn't mean much itself, it's how the hydrogen is produced that matters and determines if it's a better or worse fuel source for auto's. If your burning coal or oil to make the hydrogen then what's the point?

Anyway lets all agree the ethanol is a stupid idea and needs to be banned and should be removed from gasoline. When you mix it with gasoline you end up burning more gasoline than you did before you added the ethanol. I'm already forced to use that crap in my car and it sucks, more engine wear, less miles per gallon, and more $$ since ethanol is more expensive than gasoline. As far as I see it ethanol is a loose, loose, loose situation except for a few huge lobbiests groups in the US (ADM).

juanjux

Ethanol is not a bad idea on itself. Cars prepared to run on methanol run nicely (Koenisberg, new Saab Aero, etc). Using ethanol on cars not designed to run in ethanol is the bad idea.

rotarygod

Diesels do not run on detonation. Nothing does. This is a common misconception by people who have no idea how they work. It is a controlled burn. Go learn how they do work. They also don't need to be dirty. Take a look at any new passenger car diesel. For that matter take a look at the Audi R10 LeMans car. Not a puff of smoke out of it. Again, go learn how these engines work. Saying a diesel is dirty is like taking a cat off of a gasoline engine and complaining that it can't pass emissions. The dirty diesels you see on the road are not new designs and do not have current emissions controls on them. Stop complaining about 50's technology that is still being used. A 21st century diesel will make most gasoline engines look stupid when it comes to efficiency and emissions.

Ethanol does not increase engine wear! If you are concerned about wear, go use a better oil that is synthetic based. Where do you come up with this stuff? Go do some homework.

rotarygod

This is true. Many people don't understand this. Most only see that in a lab test, ethanol doesn't have as many btu's of energy when burned as gasoline does. However it does have something going for it. Octane level. It is a slower burning fuel. This means that we could build engines with higher comprssion ratios to make up most of the difference. Even if we didn't get all of the economy back that we had on gasoline due to the much richer stoichiometric air fuel ratio, it could get acceptably close. The downside is that we couldn't run gasoline in an engine built for ethanol as easily as it would ping like crazy. Turbocharged cars running on ethanol can actually make more power than on gasoline and can do it with less intercooling which is less pressure loss in the system.

I do agree that it isn't the best fuel as a solution for our problems. We can't make enough of it and many distilling plants making it aren't making it in the most efficient way. Ethanol's problem isn't so much from a power or mileage standpoint as it is everything else needed to use it well such as newer engine designs, transporting infrastructure, and necessary materials to make it. There are ways to increase our efficiency when it comes to production of it but as a fuel additive or standalone fuel for our current engines, it isn't a good choice. Ethanol is being made out to be better than it is for our current needs. It's more of a PR stunt right now. Then again that's all that hydrogen is as it isn't even useful.

zoom44

ethanol has one thing going for it that the "greenies" really like - its carbon neutral. If carbon diaoxide is contributing to an increase in global temperatures or to some sort of climate shift(and i am not debating those here but there is much debate to be had) then using ethanol derived from growing plants is better than fuel from oil.

all the carbon in the plant and the fuel derived from it was already in the atmosphere and then taken into the plant as it was growing. so making and burning the fuel can only release that same amount of carbon. so the fuel is carbon neutral.

the carbon in oil and the fuels derived from it was taken out of the atmosphere millions of years ago. producing and burning the fuel releases and adds this carbon back to the atmosphere now which is effectively carbon positive. if the climate change global warming model this is a bad thing. everyone would have to find a way to remove an equal or greater amount of carbon from the atmosphere. which means some form of fast growing vegetation for short term (could then be used for fuel- carbon neutral)and slow growing vegetation(sequesters carbon for a long time- carbon negative) for the long term. so more corn or kudzu or switchgrass adn trees.

or of course some other technological solution for carbon sequestration could be used. planting crops would be more economical i think.

zoom44

yeah hydrogen isnt useful

http://www.fuel-cell-bus-club.com/in...ub&tid=1&pid=2

rotarygod

Yay a bus. How many people are content with buslike performance in their own personal vehicles? I guess anyone who would buy a 100 hp hydrogen RX-8 would like it. If it's place is only on a bus fleet that doesn't need performance, then I guess that's where it should be implemented. Personally I don't see it viable when Ford needs a large supercharged V10 running on the stuff just to break the 220 hp mark.

Rothor

No-way is a small country where 99% of all electricity is made from waterfalls and hunts Whales all year around to keep Greepeace guys (un)happy.
It sure is real all right.
Norway is the 3rd largest oilexporter in the World and has 4.5 million people living there and gas is appr. US$2 per Litre = US$8 per Gallon!

A RX-8 petrol vesion (High power) costs US$90.500 due to the exteme taxation of cars (or in general).
A pint of beer in a bar is US$12. The politicians means this would make it nearly impossible to become an alchoholic since you can't afford it...

About rotary engine and hydrogen.
Some of the reasoning that the RX-8 only puts out 109hp on hydrogen is to reduce consumption as RX8 is the only car Mazda produce with a rotary engine and you cannot place a much bigger hydrogen tank with 350bar pressure in the boot then they've already have done.
Also, since the engine is dual fuel and that the thermal efficency on a rotary engine sucks on low rpm it leaves deposits witch again when running on hydrogen leads to misfire. The setup is full of "Engineering choices" = compromises.

I belive next step for Mazda will be the Mazda5 rotary engine/hybrid where they can optimise the rotary engine from hydrogen fuel alone and I'm sure it will be around 150hp and maybe single sparkplug per rotor.

The benefits of a rotary engine on hydrogen, compared to a piston engine is that there is no valves i.e. exhaust valve that gets accumulative hotter the more load you put on the engine. Thats why Ford needs a huge piston engine to acheive its 200hp.
On petrol the fuel ratio is optimised (all this is simplified) is 14.6 and is very energy dense.
Hydrogen has 34 and this indicates a very volumnious gas and is the biggest problem when it comes to storage, thereof the high pressure tanks. Unfortunately you don't get twice the amount of gas in a tank by doubling the pressure.

There is also a experiment in Norway on an island where they have windmills that produce electricity (a more than actually needed) and uses the surplus power to run a electrolyser that splits water (H2O) and stores this until there is a wind brake (or the wind is to strong) and then there is a generator running on hydrogen that kicks in to produce electricity to keep the grip going.

The generator is a 11ltr piston engine and produces 55kW power.
I hope the next generator, since the fuelcells are not an alternative for the next 10-15 years is going to be a Renesis hydrogen powered engine giving upto 75kW
of power and 70kW of heated water.

If you think of it, yes a fuellcell is more energy efficient making power than a rotary engine, BUT when you also take into consideration the heat (for water. etc) the total energy input/output is actually better using the rotary engine than a fuelcell. On top of that you have the cost in benefit of the rotary engine and not at least, What do you dowith a fuelcell thats "used up" after only 2.000-10.000 hours. It's full of exotic material putted together that nobody yet have fould a way to recycle it.
What do you do with a rotary engine (can run 20.000 hours in generator mode) that is worn - It can be refurbished and run again or if a total crash, most of the parts is recycleble - to beer cans?

Ref to diesel and rotary engines. The full diesel cycle cannot (within a certain cost limit) be obtained, but it is fully possible to run the rotary as a diesel or multi-fuelled engine with "sparkplugs" and consumption similar to petrol.

But again, the rotary engine has bad thermal efficency at low rpm/low load and can be optimised to around 35% thermal efficency at certain rpm's and loads. This is actually amongst the very best of any engine.

Rgds,
Rothor
Living in the home of Vikings, the first to find the Americas.

rotarygod

That's dead wrong! There is already one running on true compression ignition. It uses indirect injection in a prechamber and a glow plug for startup. It's built by a company called PATS and is an apu (auxiliary power unit) for corporate jets. It is very efficient.

Rothor

I totally don't agree as a true diesel engine is defined as "An internal-combustion engine that uses the heat of highly compressed air to ignite a spray of fuel introduced after the start of the compression stroke"

The Pat has "normal" petrol compression and also charged cooling i.e Norton bike engine.

That is why I specificly said the full diesel cycle, you can run the rotary on diesel as fuel, but NOT as a diesel engine.

Rgds,
Rothor

rotarygod

It's an air cooled engine with no spark plugs running on diesel fuel. What part of that is not the diesel cycle?

Rothor

Maybe the Heat of highly compressed air to ignite a spray of fuel part...

Rgds,
Rothor

Rothor

How do I paste a picture in here?

Rdgs,
Rothor

therm8

I could live with a 100hp hydrogen engine...in a 1000-1500lb car. Not in a 3000lb car. 100-150hp in a lightweight car will have plenty of performance. My biggest question is can I fill the tank back up overnight at home? Probably not, and therefore it becomes useless. 60 miles gives me 2 trips to work and back, without deviating from the course at all. Now that range would probably go up in a much lighter car, but 90% of the people in the US would never give up their overweight moving couches. If hydrogen is to be the solution, there needs to be a massive rearranging of the public's priorities when it comes to owning a vehicle. Car companies will never convert to a lineup of lightweight hydrogen cars, without being forced to.

-----
On wind farms: there's a giant fight over building one where my parents live. The arguments against it are the typical, it'll kill the birds, lower property value, hurt the landscape etc. The same county is building a coal waste power plant in 2 years.... People are stupid, what else can I say.

-----
The future of nuclear power is looking up. All current civilian reactors are ancient by nuclear standards. The new designs that are slated for construction will be much more fuel efficient, and therefore produce much less waste. The biggest concern here is retarded ******** wanting to blow them up in the name of God.

therm8

pictures: link them using the img button at the top of the reply screen, or use the manage attachments mid way down the reply screen

edited: misread something

Rothor

I got a great picture of the Pat power engine and it is NOT air cooled, its water jacked and is charged cooled, meaning the inside of the rotors is aircooled insted of oilcooled as Mazda.

On the picture you will see that their using a glowplug to heat up the prechamber that the injector sprays thru and into the combustion chamber. The prinsible is quite similar to the old Mercedes diesel engines, only they used it as cold starting device and had a compression ratio of 18:1 to obtain the Heat of highly compressed air to ignite a spray of fuel.

I also added two pictures with a true diesel rotary engine that Rolls Royce made. It was full of exotic materiels to such a cost it couldn't be produced. Two stages to get the high compression.



Rgds,
Rothor

rotarygod

There are 2 pictures of it on Craig's rotary pages. I've seen them. Charge cooled, air cooled, the point is that air is cooling a part of the engine. So the outer housings are cooled with coolant but the rotors are air cooled. Big deal. The cooling system does not dictate whether or not it is a diesel. The compression ratio does not dictate whether or not it is a diesel. The only thing that makes it a diesel is if it compression ignited. This is not the same as just burning diesel fuel. There are even 2 stroke diesels out there but still diesels nevertheless. PATS does not use any additional compressed air. It is a true compression ignited engine. That makes it a true diesel.

Rothor

It is definitely NOT a true diesel engine since its using a glow plug/added heating at all times and not by using the heat of high compression to ignite. This has been thoroughly discuessed since Rudolf Diesel claimd his patent and won and have been the stardard ever since.

Rgds,
Rothor

Rothor

I think we can conlude with that we argee to disagree on this subject.

Just for fun I'll added some material with regards to the RPI engines "running" on diesel.

So dream on..

Rgds,
Rothor

rotarygod

Theirs aren't diesels. It's not the fuel used that makes it a diesel. It's the combustion process.

Rothor

The RPI "family" of engines used Stratifeid charge to set fire to the fuel, wether it was diesel, kerosene, JP5, JP8 etc didn't matter. It is definitely not a diesel engine.
I've worked on these engines so I know.

Rgds,
Rothor

Rothor

Thanx Term8!

rotarygod

Mercedes and Curtiss-Wright both used spark ignition. I've even got book chapters devoted to each engine.

Rolls-Royce did it the hard way. They didn't need 2 rotor stages. All the larger rotor is, is a positive displacement supercharger. A roots blower on a rotary would do the exact same thing. This is actually what was done with many bull dozer engines of the 70's. Low static compression ratio but with a geared blower to raise the effective compression ratio.

EdwardsB

We also have a hydrogen powered bus/PSU owned cars here is State College, PA. The rest of the public transport is natural gas powered.

Also on the note of hydrogen production one professor doing research here found a way to burn salt water with radio waves at a certain frequency. From what I read he uses the radio waves to break the water down and out of it he somehow he produces hydrogen which burns. And I dont think we are going to run out of sale water any time soon?? But still it does take more energy to produce the hydrogen that you get out of it.

This just goes to show that just because right now we cant produce it cheaply doesn't mean in a few years someone wont just stumble upon it. Because how many things has man-kind found out by accident, while trying to do something else.