Notices
RX-8 Discussion General discussion about the RX-8 that doesn't fit in one of the specialty forums.
Sponsored by:
Sponsored by: CARiD

Hydrogen RX-8 vs Hydraulic RX-8

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 03-03-2008 | 05:20 PM
  #1  
bs101's Avatar
Thread Starter
Registered User
 
Joined: Jan 2008
Posts: 11
Likes: 0
From: Madison, WI
Hydrogen RX-8 vs Hydraulic RX-8

I don't understand why Mazda is messing with a hydrogen rx8 when they could adapt a hydraulic system much easier, gaining power and mpg.

This is the future of hybrids because it's such a simple design, unless the whole paradigm of "cars" is changed into 600lb unibody 3 wheelers.


This article isn't spanking new, but it is a good source of info concerning hydraulic hybrids.

http://www.nytimes.com/2006/06/25/au...rssnyt&emc=rss
Old 03-03-2008 | 05:39 PM
  #2  
CyberPitz's Avatar
Huge hole is huge
 
Joined: Feb 2008
Posts: 3,191
Likes: 1
From: Joplin, MO
It's good to see some new concepts rolling out the door, instead of the hydrogen/electric cars being the biggest contenders. Too bad these ideas weren't implemented many years back before we NEEDED them...but better late than never
Old 03-03-2008 | 05:48 PM
  #3  
77mjd's Avatar
Registered
 
Joined: Jun 2007
Posts: 1,134
Likes: 1
From: Sheboygan Falls, Wisconsin
Interesting. I think ethanol is a complete waste of time and I don't think hydrogen is the answer either. Nice to see there are other ideas out there. I still think an electric assist could work in an 8 to help low end. don't know if the wieght of that would be a problem though.
Old 03-03-2008 | 05:54 PM
  #4  
bs101's Avatar
Thread Starter
Registered User
 
Joined: Jan 2008
Posts: 11
Likes: 0
From: Madison, WI
I've seen articles about hydraulic hybrids since 2004... so idk what the hold up is.

I completely agree 77mjd about ethanol being a waste of time. I've written a few class papers about it's damaging effects to engine components and it's reduced energy potential (not to mention the lack of byproducts and increase in food prices).

My largest concern is the weight of the addition hydraulic components (much like an electric assist system would add also) the 22gal hydraulic fluid drum would be hard to accept by those who gut their entire interior and run steelies.
Old 03-03-2008 | 05:55 PM
  #5  
Soapflake's Avatar
Registered
 
Joined: Dec 2007
Posts: 305
Likes: 0
From: Hagerstown, MD
The rotary engine, believe or not, is the best engine for hydrogen fuel. Its safe to burn and it still gives us that rotary noise we all love.
Old 03-03-2008 | 08:08 PM
  #6  
daisuke's Avatar
rotorized!!!
 
Joined: Feb 2006
Posts: 653
Likes: 0
From: San Luis Obispo, CA
ethanol fuel as produced in the US (from corn) is a joke and an utter waste of resources. Brazil has had the right idea since the mid 70s and makes ethanol fired cars, theirs is the right track when it comes to that because they use depleted sugar cane.

I like the hybrid ideas, but I think compressed air is the best way to go, you can refill it in a matter of minutes from a compressor.

A hybrid pneumatic wankel would be fun to have, it would sound like a turbine powered car
Old 03-03-2008 | 08:34 PM
  #7  
b'Eight''s Avatar
Registered User
 
Joined: Dec 2003
Posts: 168
Likes: 0
From: PA
It sounds like a hydraulic accumulator system

The accumulator are pressurized with nitrogen. It sorta acts like a capacitor but for hydraulic systems. I have a background in fluid power.
Old 03-03-2008 | 09:05 PM
  #8  
Easy_E1's Avatar
Registered
iTrader: (2)
 
Joined: Sep 2005
Posts: 7,675
Likes: 5
From: Bellevue WA
Basic Accumulator. A bit more PSI than the ones I deal with, but none the less the same theory. The ones I see only hold about 500 PSI. They are there if the system has a failure and you need to continue hyd. pressure for a short period of time.
This system just charges an accumulator and expends it's charge on vehicle travel start. As an assist to the drive. Allowing the engine to maintain a constant rpm. Basically removing the take off load on the engine.
Hydraulic power assist.
Old 03-04-2008 | 12:11 PM
  #9  
shinka1313's Avatar
Registered User
 
Joined: Jun 2006
Posts: 20
Likes: 0
From: Louisville
Hydraulic assist works great but has a few drawbacks: expensive, added complexity, noisy, and heavy. Electric hybrid does the same thing at lower cost without the noise.

Hydrogen works great but free hydrogen does not exist in nature. Environmental cost of making hydrogen exceeds benefit of using it in vehicles.
Old 03-04-2008 | 03:31 PM
  #10  
8 Maniac's Avatar
Senior Member
iTrader: (1)
 
Joined: Oct 2005
Posts: 3,814
Likes: 1
From: Aki City, Japan
While I dont believe hydrogen is the answer, I believe we could find an efficient way of getting hydrogen if we needed to. Mind you I dont really know specifically about any concepts, I dont see why it wouldn't be doable.
Old 03-04-2008 | 07:39 PM
  #11  
mikesol's Avatar
gas kilometerage
 
Joined: Sep 2007
Posts: 203
Likes: 0
From: vancouver bc
Hydrogen makes sense ONLY when you use a very clean source to make it.

For example, if you build a hydroelectric dam which generates electricity from the movement of water, and then run some of that water through electrolysis to make hydrogen, you're producing it in a sustainable and logical manner.

If you use solar, wind, tidal, or geothermal power and water electrolysis, you're also making it in a logical fashion.

Clean nuclear power is fine too and a really good option for high volume use. I don't know why environmental types are so scared of nuclear power, it is non-polluting and super efficient.

However, if you start from a hydrocarbon (usually from petroleum), or if you use water electrolysis but you're using a big coal or gas power plant to get the electricity, you're defeating the whole goddamned purpose.

One of the best ideas I have seen is on-site generation of hydrogen: the gas station makes its own, using whatever power source is convenient. That way you don't have big tanker trucks running around to distribute it. Some places could make it with solar power and sell it for dirt cheap; some would be using grid power and charge you a rate based on that.

Either way, hydrogen is not the worst idea for a fuel. Batteries would be nice, but no technology is good enough yet.
Old 03-05-2008 | 10:39 AM
  #12  
Tim Tim Tim's Avatar
auto suckkssssss
 
Joined: Oct 2007
Posts: 397
Likes: 0
From: Sandy, Utah
well it says right in the article that the hydraulic hybrid will really only work for larger vehicles (im assuming its the larger motor that matters). The 1.3L rotary doesnt really fit into that category.

It really depends what goal your trying to reach as to what fuel. Ethanol is a great fuel if your just trying to get off the foreign dependency of oil. It sure as hell isnt efficiant but you can also make great power running it. Look at the koenigsegg ccxr http://www.koenigsegg.com/cars_2.html. It picks up 200 hp by switching from 93 octane to the e85 (of course tuning and stuff involved). Id like to see the stuff go hydrogen personally.

Electric is nice but its just going to move the dependency to the electric companys instead of the gas station.

Battery's are just to heavy, they will work fine for suv's and stuff but what about the performance cars? imagine the rx8 with an extra 500 pounds of battery's in it.. Ill pass

One of the best ideas I have seen is on-site generation of hydrogen: the gas station makes its own, using whatever power source is convenient. That way you don't have big tanker trucks running around to distribute it. Some places could make it with solar power and sell it for dirt cheap; some would be using grid power and charge you a rate based on that.
That is my personal favorite idea. It seems like a win win win win win situation
Old 03-05-2008 | 10:44 AM
  #13  
Rote8's Avatar
Registered
 
Joined: Oct 2007
Posts: 1,574
Likes: 2
From: Boosted...
Originally Posted by Tim Tim Tim
Electric is nice but its just going to move the dependency to the electric companys instead of the gas station.

Battery's are just to heavy, they will work fine for suv's and stuff but what about the performance cars? imagine the rx8 with an extra 500 pounds of battery's in it.. Ill pass
Super Capacitors are on the way to replace batteries.
Old 03-05-2008 | 11:09 AM
  #14  
Rootski's Avatar
DGAF
iTrader: (1)
 
Joined: Jan 2006
Posts: 1,953
Likes: 0
From: Austin, TX
Honda is selling a system with its FCX hydrogen car that's a home filling station. Everything you need to make hydrogen is pumped into your home, so why bother with a "gas" station at all? It can run from the power grid or from solar panels, so it's as clean as you want. The main advantage of using hydrogen in a rotary is that unlike other hydrogen prototypes, which are hydrogen/electric, you can still burn regular old petrol just like a normal RX8 and never know the difference. I love that.
Old 03-05-2008 | 03:34 PM
  #15  
bs101's Avatar
Thread Starter
Registered User
 
Joined: Jan 2008
Posts: 11
Likes: 0
From: Madison, WI
Originally Posted by Rootski
...The main advantage of using hydrogen in a rotary is that unlike other hydrogen prototypes, which are hydrogen/electric, you can still burn regular old petrol just like a normal RX8 and never know the difference. I love that.
but you'd have to completely drain the tank and wipe it all down before switching it to hydrogen vice versa right?
Old 03-05-2008 | 06:45 PM
  #16  
Tim Tim Tim's Avatar
auto suckkssssss
 
Joined: Oct 2007
Posts: 397
Likes: 0
From: Sandy, Utah
why would you want to run regular gas if you could use hydrogen anyways. exp if you can make it at your own home
Old 03-05-2008 | 07:34 PM
  #17  
Soapflake's Avatar
Registered
 
Joined: Dec 2007
Posts: 305
Likes: 0
From: Hagerstown, MD
Originally Posted by bs101
but you'd have to completely drain the tank and wipe it all down before switching it to hydrogen vice versa right?
The concept car switches between fuel types with a button.
Old 03-05-2008 | 08:16 PM
  #18  
bs101's Avatar
Thread Starter
Registered User
 
Joined: Jan 2008
Posts: 11
Likes: 0
From: Madison, WI
Originally Posted by Soapflake
The concept car switches between fuel types with a button.
...so would it be possible to 'adjust' this gen of 8's to do that as well? (within a reasonable price)
Old 03-06-2008 | 12:42 AM
  #19  
Soapflake's Avatar
Registered
 
Joined: Dec 2007
Posts: 305
Likes: 0
From: Hagerstown, MD
Originally Posted by bs101
...so would it be possible to 'adjust' this gen of 8's to do that as well? (within a reasonable price)
Not in english, but if you scroll through you can see how they have a tank on each side for each type of fuel:
http://youtube.com/watch?v=xc8ciNoUntk
Old 03-06-2008 | 01:55 AM
  #20  
rotarygod's Avatar
Registered
 
Joined: Apr 2003
Posts: 9,134
Likes: 25
From: Houston
I've had the same basic idea but in an even simpler way to accomplish. Air. Nothing but air. You have a small piston pump installed in the drivetrain. It's job is nothing more than an air compressor. By varying a couple of simple valves, you can either make it compress air or use stored air to send power back out. The engine never has to stop moving or change directions to do this. When you hit the brakes, instead of using friction to stop, you use the available intertial energy to fill up a small air tank. When you accelerate, this stored air is now sent to the piston pump to help put the power back to the wheels. There is no hydraulic system to maintain. There is no fluid to add weight. Since the pump is nothing more than an airpump, it doesn't need to be big and can be made out of aluminum. It doesn't need an oil supply aside from a small onboard closed lubrication reservior and it doesn't need water.

A system like this won't do anything for highway mileage but it would help city mileage numbers improve. Theoretically it takes the same amount of energy to accelerate a car from point A to point B over a certain amount of time as it does to decelerate the same vehicle the same distance over the same amount of time. This of course isn't completely true due to rolling resistance from friction as well as wind resistance but it's a good estimate on potential. We also know that we can't easily utilize 100% of the available waste energy. The key is to use some of it rather than none. Let's say our vehicle gets 18mpg city and 24 mpg hwy. If we could get 100% efficiency from this system, we'd theoretically also get around 24 mpg city. This isn't going to happen. What if we could get 50% efficiency? That would be around 21 mpg city which is a noticable improvement with no fluids to worry about. I think this would be a better idea. Since the small "engine" would only be for air, it could be double acting which utilizes both sides of the piston. This would further save space. It doesn't need to be large. There is only so much available energy to capture which means the pump only needs to be so large and the air tank only needs to be so large. There's a relationship between it all and it wouldn't be as big and heavy as either current hybrid or hydraulic technology. That's just how I'd personally do it.
Old 03-06-2008 | 02:18 AM
  #21  
daisuke's Avatar
rotorized!!!
 
Joined: Feb 2006
Posts: 653
Likes: 0
From: San Luis Obispo, CA
rotarygod

Air is my vote too, but I was thinking about it the other way around. Given that the power needed to cruise is but a fraction of the power needed to accelerate I was thinking more along the lines of having a high pressure air tank that would feed the rotors themselves directly from injectors in the housings to supply power at cruise speeds, either to a third specialized very high compression rotor which is only air driven, or the entire engine itself would be a hybrid with the 2 rotors being air or fuel powered. So you use the gasoline to get all your standard high performance power, and then switch to air when no more acceleration is needed, that way you cruise on the highway with 0 tailpipe emissions and your gas mileage increases to something like 50mpg or more. Make the air tank refillable at special air-up stations and it goes up even further.

You do run into problems with thermal cycling by doing this, but I'm sure that an engine with a tendency to overheat could manage to stay warm.

Current hybrids specialize in city driving, but for anyone who wants to cruise for long distances, the gas mileage advantage kinda evaporates, this would be the alternate approach
Old 03-06-2008 | 05:50 AM
  #22  
Rote8's Avatar
Registered
 
Joined: Oct 2007
Posts: 1,574
Likes: 2
From: Boosted...
Forget Hydrogen....

We have more energy than ALL the oil in the world off the coast of the Carolinas in a single deposit of Methane Hydrate.
There are also similar Methane Hydrate deposits all over the world. (except in the mid-east )

MEthane.......
Old 03-07-2008 | 07:38 PM
  #23  
Tim Tim Tim's Avatar
auto suckkssssss
 
Joined: Oct 2007
Posts: 397
Likes: 0
From: Sandy, Utah
I dont think they want to switch back to another non renewable source for our power. now that I think about it, I Really dont see why air wouldnt be an easy/good choice for the rotary motor.
Old 03-08-2008 | 01:17 AM
  #24  
daisuke's Avatar
rotorized!!!
 
Joined: Feb 2006
Posts: 653
Likes: 0
From: San Luis Obispo, CA
because it's completely clean at the pipe, doesn't produce any byproduct (like depleted batteries), and even if you're using an external air source, the compressor used would probably be more efficient than other sources of generating stored power.
Old 03-08-2008 | 10:43 AM
  #25  
kersh4w's Avatar
Hit & Run Magnet
iTrader: (3)
 
Joined: May 2007
Posts: 6,690
Likes: 3
From: DC Area
backers say the ideal vehicle for this system is a garbage truck, but that it could work well in vehicles as small as S.U.V.'s.
also, let me know when your rx8 can accommodate 4 22 gallon tanks.


You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: Hydrogen RX-8 vs Hydraulic RX-8



All times are GMT -5. The time now is 04:16 PM.