zoom44

see that Fred! thank you richard, fred just refused to believe no sour grapes from me- well except on the naming of the thing- if its my idea why should someone else get to name it? although "jet engine" really is a good name and i am very happy with it :D

on the paper comment- it is in a post on another website(McCulloch Supercharger Discussion Area) from one Jim Moody from july something this year. here is the link to his post and i quote "If Richard Paul ever got around to writing a piece on them I'd happily post it on the site - under a section entitled "the rivals"."

i think now upon reading it again that he is just saying he would like to have an article written by you not that he is actually waiting on one. there are a couple other mentions of you on there dealing with a particular latham charger and whether it has a particular 3 bolt stud pattern for mounting it.

rotarygod

I do believe. Just not you!!! Hehe! :p

zoom44

yeah but you're voting for me anyway right? i mean its better to not believe me and still vote for me than doing the same for the other 2.

here i am a mod and going way off on a tangent. i should be ashamed. back to the regularly scheduled program.

shawnio

Money is always the bottom line, 1% higher efficiency just means x amount of dollars saved at the end of the year. Does this translate to more money in your pocket? What was the initial investment? How much money will it cost to retrofit the fleet, or whatever, for what amount of money saved after what period of time? Perhaps these turbochargers are being used by others and so the company making the product can make more money off of bulk sale and save the buyer money. Perhaps this design of ocean carrier is only planned to be used for x amount of years, and the money gained at the end of the lifetime of the ocean carrier is nil. Perhaps the demand of compressors is greater than the ability for certain companies to produce them, and so that would lead to extended down time for replaced compressors and lost money. Really, we can speculate all we want. Richard Paul has given a lot of info on how his compressor compares others. It all depends on what your goals are.

rotarygod

Just as a little bit of interesting side information, when General Electric designs a new jet engine they do durability tests. At their test facility they set an engine up on a stationary stand. Much like a dyno they start the engine and let it run. The incredible part is that they run it at full thrust for 3 months straight! The only stops they make are just to do quick inspections to the parts. During these tests they run lots of debris through the engine. Anything from ice to water to small birds. Kind of makes you feel good about jets when you are on a several hour flight over the ocean somewhere.

globi

I think this is not entirely correct. The Toyota Prius has an electric motor/generator with 50kW. And you wouldn't need more than 15kW to power a reasonable supercharger for a 2.0 l engine.
It's true you couldn't use it for any sustained period of time. But what are you using the supercharger for? Mainly to accelerate - where can you drive 150 mph for a long period of time? Let's face it, most people don't drive at WOT more than 5% of the time. Even brakes of Formula 1 cars transfer about 40% of the mechanical energy generated by the engine into heat energy. (Besides even if you'd power the electric supercharger with an electric generator at the same time you'd still end up with a net power gain.)
As soon as we have flywheel/motors/generators and a 42V system and therefore more electric power on hand we'll see electric superchargers or electric turbos (as we'll see electric AC, electric oil and water pumps etc.). Heck, we might even see electrically powered valves at some point.

And I believe this axial compressor might be perfect to accomodate a high frequency electric motor in the center (no gears necessary). But I realize that we're not quite there yet.

Tresch

Actually, and by no means am I an expert, I believe using the electrical motor to drive the flywheel directly WOULD be more effecient than using it to drive a compressor, simply due to the raw efficiency of an electrical motor to convert electrical energy into mechanical energy.

I'm kinda half pulling these numbers out my ***, but gas engines are only like 40% efficient or something. Something really nasty terrible. Electrical engines, however, are much higher, like 70 percent? Maybe higher than that? I'm in a slight hurry or I'd dig up some hard numbers. Could I get some help here from a smart person? Feel free to tear me up if I'm totally wrong :P

Regenerative braking is cool, but the nice thing is the ability to efficiently transmit that electrical energy to mechanical energy, and the electric motor is about the most efficient device on earth for that purpose (from what I know). Using all that potential to provide aid for a device as terribly efficient as an internal combustion engine would be a waste.

Only reason we use gas engines is because we can store a lot of energy for them in a small package (gas!). Electrical energy is harder and heavier to store. If we could build a battery that held as much energy as a 12 gallon tank of gas, and weighed the same.. there would no longer BE internal combustion cars.

globi

Regarding efficiency that's correct. However an electric Motor with 20 HP might generate an extra 80 HP if used to supercharge air. So you have a significant power benefit.

I'd say it's a concept for a more efficient sports car. Otherwise I agree I wouldn't suggest that a Toyota Prius should supercharge its own gasoline engine with that 50kW electric motor.

Ajax

You're missing 2 factors and then we need to get back on subject.
First, you also need the ability to recharge a vehicle in a reasonable amount of time and at a number of different locations. If you have to charge the vehicle for 8 hours to get the effective 12 gallon charge, I hope you're not planning any long distance trips, furthermore, I hope you're charging everyday.

Second, charging and using a battery diminishes it's life. The more often you recharge a cell, the more likely you are to damage that cell and reduce the maximum effective charge of the cell. Lithium Ion are not as strongly affected by that property, however, they are extremely adversely affected by 2 things: overcharging and over-discharging.

Lithium Ion batteries will charge up to a point and then continiued charging will only result in less charge on the battery. At that point, the temperature of the battery will also spike rapidly. By monitoring both the charge and the temperature and charging to the spike (peak charging), you can get the maximum charge out of the battery without overcharging it. Most companies build overcharge protection into their battery circuits, however, over-discharge is something more complicated to prevent.

Over-discharge is very bad for lithium ion batteries because it causes the cells to reverse polarity. This is generally why cell phone battery lifespans get shortenned so much over time. You see, a lithium ion battery is made up of many lithium ion cells. Each cell holds a charge and the combination of all these cells makes up 1 battery. Now when you use that battery the cells begin to discharge but not necessarily uniformly. Some cells will discharge slightly more than others. If any of the cells over-discharge, their polarity reverses and they can no longer be charged with the rest of the battery so they're no longer producing any useful charge. If you continue to use that battery after cells have been over-discharged and expect to maintain the same lifespan, you will probably over-discharge other cells and the battery life will get even shorter.

As far as electric vehicles go, we built 1 fully electric and 1 hybrid hydrogen electric while I was in school. The fully electric was based on a chevy lumina running 2 battery packs of lead acid batteries (very heavy, very good charge but poor lifespan) and 2 90 horsepower motors belted together and bolted to the driveshaft to turn the wheels. Acceleration was totally linear as there was no transmission. The vehicle had 3 gears, forward, off and reverse. The longer you held the gas pedal down, the faster it would go until the 3500 lb lumina reached terminal velocity (we clocked it at about 90 miles per hour). It had regenerative braking as well and well, it wasnt all that useful but it could extend the life of the vehicle when coasting and braking.

As far as acceleration went, it was pretty sluggish off the line but most of that was because of the weight. Those motors were putting approximately 160-170 horsies to the wheels so we were seeing some pretty good power. We dynoed the vehicle like 4-5 times.

In a race between our lumina and the hydrogen/electric explorer, we kicked it's butt :b Even with 30kw of power, we smoked that explorer like you wouldnt believe and get this, the 2 vehicles weighed about the same! The explorer w/no engine is around 3800 lbs. It ran with 2 lithium ion battery packs (the ones the prius uses) and a honeywell hydrogen fuel cell. It was twin turbocharged (technically, lol, it had 2 blowers that had to be on to keep enough air moving through the fuel cell to keep power output up) and required fills of hydrogen and de-ionized water (which we can make at TTU) constantly. Top speed was an abysmal 45 mph and at that speed those 2 blowers were so loud that i couldnt imagine a traffic jam full of them.

Ok.. now.. let's get back on topic! :b

Tresch

I agree that current battery technologies make this impossible.. this is why we have gas cars. It was more.... a hypothetical statement.

back on the topic of efficiency (would this even be considered properly on topic?) remember that you cannot add power simply by adding air, you must also add fuel. Power added directly to the flywheel by an electric motor powered by regenerative braking is essentially (weight aside) free. You could also have an electric compressor that drove more air into the engine, which could provide for more POWER in the end, that air would have to be accompanied by more FUEL as well, which would offset, possibly negate, any efficiency gains.

Main Entry: ef·fi·cien·cy
Pronunciation: i-'fi-sh&n-sE
Function: noun
Inflected Form(s): plural -cies
1 : the quality or degree of being efficient
2 a : efficient operation b (1) : effective operation as measured by a comparison of production with cost (as in energy, time, and money) (2) : the ratio of the useful energy delivered by a dynamic system to the energy supplied to it

Now, since we all know that we're really comparing turbo to electrocharge, we of course understand that we're already going to be using extra fuel. The assumption is that since we don't have to restrict exhaust gas (turbo) or run a pully on the motor (super), that we're gaining efficiency. And I would have to agree!

However, for practicality's sake, we also have to understand that braking is not a consistant or plentiful enough source of energy to power a compressor for any extended period of time, so, for any real useable power (i.e: to keep the compressor spinning when we want/need it) we'd need to suppliment the electrical energy to the compressor by another source, which would be a generator, which would reduce efficiency.

So, in conclusion, the winner IS....

*shrugs* hell I dunno, what do I look like, a scientist?

Tresch

Actually, I'm going to have to say that Richards Axial flow supercharge wins, because it's much shinier than the other ones.

globi

Hey the proof is in the pudding. Currently you can purchase about 5 hybrids: Honda Insight, Civic, Accord, Ford Escape and Toyota Prius.
They're all fitted with NiMH batteries. So the batteries are obviously working.

It be interesting to see, what would happen if the new Honda Accord V6 hybrid would be electrically supercharged.

That's the point.

At full throttle you reach 150 mph in less than 30 seconds. Why do you need electric power for a sustained period of time? Are you living on some salt lake?

Braking energy is a lot of energy. Again the proof is in the pudding. If it wasn't worth anything the Hybrids wouldn't get such a great mileage.

zoom44

axial flow superchargers win because they are shinier!! nuff said back on topic-


which is whatever richard was talking about last- i think it was my invention of the "jet engine"

rotarygod

This isn't a thread on hybrid electric cars. It is on axial flow superchargers. Hybrids may be making their way to market, but they aren't winning any races anywhere regardless of how good of an idea it is.

Ajax

dude! i invented the jet engine.. no wait.. i invented the exploding blender.. either way, it's all about the same!

Richard Paul

iTrader: (5)

Just to add to RG's comment on the GE engines, they also do shear wind tests. I think I posted this before but it is well worth another look.
This is the engine for the 777 and is being tested for a 90 degree wind shear test. Thereby unloading the airflow into the compressor. Very violent reaction.
Don't sweat it though this cannot happen in real life.

BTW, thanks for the education on the batterys. Very interesting, never knew that about the charge/discharge on the lithium ion bat.

Hymee

iTrader: (1)

I like that - an actual photo of what can't happen in real life

Cheers,
Hymee.

Ajax

No problem.. Nickel metal hydride batteries exhibit the same characterstics. nickel cadnium also exhibit the charge charactersitics but at overdischarge, the cells tend to just die rather than reverse polarity.

I learned way too much about batteries in school.

And yea, that picture is awesome. I remember when you posted it before.

globi

Who's talking about hybrid cars? I was just trying to make a point that the axial flow supercharger might be an ideal application for an electric supercharger - that's it. But I guess it wasn't clear enough.

And regarding race cars: Regenerative braking is prohibited in the Formula 1 and I'm sure FIA wouldn't have prohibited it if they didn't think that any team could benefit from it.

Gord96BRG

True - about 4 or 5 years ago, McLaren had developed and begun testing a regenerative braking system. It was definitely advantageous, so (typically), Ferrari protested and that is why the FIA banned it.

Regards,
Gordon

tokenbrit

It does make a lot of sense to use the energy used in slowing down to help you accelerate back up to speed a little quicker, but this is a long way off for commercial vehicles.
As far as I'm concerned, it's alright talking about stuff that isn't really a reality at the moment. When it interferes with progress of stuff that is a reality, it becomes a problem. That isn't the case here.
I think it is good to keep this thread kept alive by talking about this stuff than letting it die?...
Personally, I would prefer pictures tho....

globi

I agree as I mentioned before we're not there yet.

Here's your picture of a (less sophisticated) electric supercharger. But since it's not combined with regenerative braking it's not really that useful. http://www.boosthead.com/home.php
But it can compete against a N2O system, since charging the batteries or capacitors is eventually cheaper than purchasing N2O bottles.

guy321

Maybe Richard should develop an electric S/C for the Civic Hybrid.. My cousin has one of those in L.A. It could definitely use more power!!! We went to Vegas in that thing, I didn't think it would get up some of the mountains! :D

John Corbitt

Ironicly, The largest cruise ship is powered by an axial flow jet engine that runs generators that power electric pods.

John

Richard Paul

iTrader: (5)

Now Hymee, you shouldn't make fun of GE or the FAA, you're going to have to test your product that way too. At least if you want it to fly.

and cheers to you