Go Back   EcoModder Forum > EcoModding > The Unicorn Corral
Register Now
 Register Now
 


Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 03-12-2013, 09:25 AM   #31 (permalink)
EcoModding Apprentice
 
Join Date: Aug 2009
Location: London, UK
Posts: 113
Thanks: 16
Thanked 3 Times in 3 Posts
Whether a manufacturer decides to install Seebeck devices, a 'turbosteamer' setup or a turbo-generator, there will be some increase in back-pressure as heat is turned into work during the exhaust gases' journey to the tailpipe.
The TIGERS system utilises a bypass valve for when the motor is at part-load operation, so the back-pressure is not strangling the engine.

I think any vehicle design would need to be at least a 'mild hybrid' for a turbo-gen to make sense, but it would have to be seen how much additional cost it would be incurred relative to the lifetimes fuel savings. ... it seems to me that it could somewhat improve a hybrid's highway economy; and the same may be true for large trucks (without being hybrid, even) as they are pulling under load for much of their operation.

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 03-12-2013, 11:35 AM   #32 (permalink)
Not Doug
 
Xist's Avatar
 
Join Date: Jun 2012
Location: Show Low, AZ
Posts: 10,225

Chorizo - '00 Honda Civic HX, baby! :D
90 day: 35.35 mpg (US)

Mid-Life Crisis Fighter - '99 Honda Accord LX
90 day: 30.47 mpg (US)
Thanks: 6,713
Thanked 1,929 Times in 1,466 Posts
At what temperature is a catalytic converter designed to work?
  Reply With Quote
Old 03-12-2013, 08:17 PM   #33 (permalink)
Master EcoModder
 
Join Date: Jul 2008
Location: Silly-Con Valley
Posts: 1,421
Thanks: 176
Thanked 228 Times in 176 Posts
Quote:
Originally Posted by Nerys View Post
electric motors DESIGNED right are extremely reliable.
True, but electrical connections and components multiply the number of failure points, and anything that moves or vibrates is liable to problems from that (e.g., fatigue). There is pretty much just one failure point for the drive on a conventional water pump--the belt. There can be quite a few for an electrical pump; every connection, the relays, the switches (if any), whatever controls you have on the system, etc.

You won't damage the engine if you notice that the pump is no longer working. Most people (including me!) are going to miss that for a while at least. So you need to rig up some sort of very unambiguous signal, like a loud chime or a big light, when the temp gets to a certain point. If you rely on a gauge, the one time you will need to pay attention to it you will miss it. (Murphy's law.)

An electric pump could be a win, but you would need to make the system at least somewhat fail-safe. And you'd need to pay close attention to the design and fabrication of the electrics.

IMHO.

-soD
  Reply With Quote
Old 03-15-2013, 09:59 AM   #34 (permalink)
EcoModding Apprentice
 
Join Date: Aug 2009
Location: London, UK
Posts: 113
Thanks: 16
Thanked 3 Times in 3 Posts
Quote:
Originally Posted by Xist View Post
At what temperature is a catalytic converter designed to work?
Several hundred degrees Celsius, I imagine.
But (and I assume this is where the question is leading), the ability once hot of the Cat' to remain in the "light-off" temperature zone is dependant on how the levels of incompletely burnt HCs in the exhaust gas as well as it's overall temperature.
With a correctly designed system that includes a bypass valve, a turbo-generator should be perfectly capable of operating effectively without overly cooling the cat' downstream.
  Reply With Quote
Old 03-15-2013, 02:38 PM   #35 (permalink)
EV convert
 
oil pan 4's Avatar
 
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 9,050

Sub - '84 Chevy Diesel Suburban C10
SUV
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)

Snow flake - '11 Nissan Leaf SL
SUV
90 day: 141.63 mpg (US)
Thanks: 215
Thanked 2,953 Times in 2,300 Posts
Quote:
Originally Posted by some_other_dave View Post
True, but electrical connections and components multiply the number of failure points, and anything that moves or vibrates is liable to problems from that (e.g., fatigue). There is pretty much just one failure point for the drive on a conventional water pump--the belt. There can be quite a few for an electrical pump; every connection, the relays, the switches (if any), whatever controls you have on the system, etc.

You won't damage the engine if you notice that the pump is no longer working. Most people (including me!) are going to miss that for a while at least. So you need to rig up some sort of very unambiguous signal, like a loud chime or a big light, when the temp gets to a certain point. If you rely on a gauge, the one time you will need to pay attention to it you will miss it. (Murphy's law.)

An electric pump could be a win, but you would need to make the system at least somewhat fail-safe. And you'd need to pay close attention to the design and fabrication of the electrics.

IMHO.

-soD
I run electric pumps and don't see much benifet over belt driven ones.
The only time the electric pump would shine is if you had an alternatorless power system that provided all the free electrical power you needed.

So unless you have a really good alt delete setup already well tested, up and running don't bother with an electric pump.
__________________
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.
  Reply With Quote
Old 03-17-2013, 01:48 AM   #36 (permalink)
It's all about Diesel
 
cRiPpLe_rOoStEr's Avatar
 
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 8,677
Thanks: 0
Thanked 959 Times in 849 Posts
Quote:
Originally Posted by Air-Hybrid View Post
Several hundred degrees Celsius, I imagine.
It's usually quoted to be from 500 to 650.
  Reply With Quote
The Following User Says Thank You to cRiPpLe_rOoStEr For This Useful Post:
Xist (03-19-2013)
Old 03-17-2013, 10:26 AM   #37 (permalink)
EcoModding Lurker
 
Join Date: Mar 2009
Location: SE Michigan
Posts: 66
Thanks: 1
Thanked 3 Times in 3 Posts
Honda's New Steam-Powered Hybrid Engine
  Reply With Quote
Old 03-17-2013, 02:34 PM   #38 (permalink)
EcoModding Apprentice
 
Join Date: Aug 2009
Location: London, UK
Posts: 113
Thanks: 16
Thanked 3 Times in 3 Posts
Quote:
Originally Posted by cRiPpLe_rOoStEr View Post
It's usually quoted to be from 500 to 650.
I'm not totally certain on whether a cat' is cable of being able to work to the best of its ability once it passes the 'light-off' temperature, but 'several hundred degrees Celsius' is not a bad fit for most vehicles' light-off point.
Unless there are practically no COs or HCs present in the exhaust I believe the cat' temperature is self-sustaining; plus if adding an exhaust turbine presents problems in holding the heat up enough, can't exhaust wrap be fitted?
  Reply With Quote
Old 03-17-2013, 02:41 PM   #39 (permalink)
EcoModding Apprentice
 
Join Date: Aug 2009
Location: London, UK
Posts: 113
Thanks: 16
Thanked 3 Times in 3 Posts
Quote:
Originally Posted by maxc View Post
"Honda's New Steam-Powered Hybrid Engine"
...er, new 5 years ago based on the article date.
BMW did a similar experiment, but neither system is very near being fitted to production vehicles so far as I know. ~ Steam system are heavier and more complex than a turbo-generator; nothing that I've seen seems to point to them being of any greater efficiency either... ??
  Reply With Quote
Old 03-17-2013, 03:39 PM   #40 (permalink)
EV convert
 
oil pan 4's Avatar
 
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 9,050

Sub - '84 Chevy Diesel Suburban C10
SUV
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)

Snow flake - '11 Nissan Leaf SL
SUV
90 day: 141.63 mpg (US)
Thanks: 215
Thanked 2,953 Times in 2,300 Posts
Just adding a turbo charger will add 30 to over 80 pounds depending on the application.
Adding a Rankine cycle would add much more weight for small gains.

For example classical boiler design calls for 10 to 12 square feet surface for each horsepower you hope to generate with a Rankine engine.
My turbocharger and added piping weighs about 60 pounds and generates about 40 horsepower worth of compressed air the way I use it, but I only use about 1/3 its max rated output.
The turbocharged diesel has no problem producing 2 to 3 times the horsepower and 10%-20% better fuel economy over an N/A diesel.

__________________
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.
  Reply With Quote
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com