Go Back   EcoModder Forum > EcoModding > General Efficiency Discussion
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 12-12-2010, 01:02 PM   #221 (permalink)
(:
 
Frank Lee's Avatar
 
Join Date: Jan 2008
Location: up north
Posts: 12,741

Blue - '93 Ford Tempo
Last 3: 27.29 mpg (US)

F150 - '94 Ford F150 XLT 4x4
90 day: 18.5 mpg (US)

Sport Coupe - '92 Ford Tempo GL
Last 3: 69.62 mpg (US)

ShWing! - '82 honda gold wing Interstate
90 day: 33.65 mpg (US)

Moon Unit - '98 Mercury Sable LX Wagon
90 day: 21.24 mpg (US)
Thanks: 1,573
Thanked 3,509 Times in 2,196 Posts
The "Crower" thing sounds neat and all, but it was patented in 1920 by someone else. That it's been around 90 years and never made it out of the lab begs the question of why?

http://www.freepatentsonline.com/1339176.pdf

__________________


  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 12-12-2010, 01:36 PM   #222 (permalink)
dcb
needs more cowbell
 
dcb's Avatar
 
Join Date: Feb 2008
Location: ˇ
Posts: 5,038

pimp mobile - '81 suzuki gs 250 t
90 day: 96.29 mpg (US)

schnitzel - '01 Volkswagen Golf TDI
90 day: 53.56 mpg (US)
Thanks: 158
Thanked 267 Times in 210 Posts
It is a good point, that the secondary cycles should not increase the backpressure, as that directly affects the work the pistons have to do. Heat exchangers usually involve some energy losses.

Given the pitiful energy density of hydraulic and power to weight of sterlings (think lots of little sterlings with plenty of surface area connected to a hydraulic cvt), it is looking like the most "feasible" highly efficient vehicle is going to be a (hopefully streamlined) fatass, on two wheels
__________________
WINDMILLS DO NOT WORK THAT WAY!!!
  Reply With Quote
Old 12-13-2010, 12:09 AM   #223 (permalink)
Master EcoModder
 
NeilBlanchard's Avatar
 
Join Date: May 2008
Location: Maynard, MA Eaarth
Posts: 7,873

Mica Blue - '05 Scion xA RS 2.0
Team Toyota
90 day: 42.48 mpg (US)

Forest - '15 Nissan Leaf S
Team Nissan
90 day: 156.46 mpg (US)

Number 7 - '15 VW e-Golf SEL
TEAM VW AUDI Group
90 day: 155.81 mpg (US)
Thanks: 3,388
Thanked 2,883 Times in 1,812 Posts
So, why do piston / connecting rod / crankshaft designs seem to hit the efficiency wall at 38%? What is holding them back from getting closer to the 54% theoretical limit? The beginning of this thread has about three new rotary designs -- do any of them look to exceed 40%?
__________________
Sincerely, Neil

http://neilblanchard.blogspot.com/
  Reply With Quote
Old 12-13-2010, 12:25 AM   #224 (permalink)
Master EcoModder
 
Join Date: Apr 2010
Location: belgium, wi
Posts: 262

Bus - '94 Ford School Bus huge

Stupid - '01 Chevy Blazer LS
90 day: 21.38 mpg (US)

hawk - '00 Honda Superhawk
Thanks: 2
Thanked 24 Times in 19 Posts
You seem to be caught on the 38% number, but what of the ones that are rated higher? How about the VAG engines from VW and Audi? And why does the efficiency of very large engines exceed that of smaller ones? Here is a related question to that... Why will a 3 cylinder 1.2l typically have a better thermal efficiency than a 4 cylinder of same size? I would say that there has been a good amount of discussion on why we havent seen this 54% theoretical efficiency, and I dont know what you are looking for in our answers as this is at least the second time you have asked this after getting many answers.
  Reply With Quote
Old 12-13-2010, 12:18 PM   #225 (permalink)
Master EcoModder
 
NeilBlanchard's Avatar
 
Join Date: May 2008
Location: Maynard, MA Eaarth
Posts: 7,873

Mica Blue - '05 Scion xA RS 2.0
Team Toyota
90 day: 42.48 mpg (US)

Forest - '15 Nissan Leaf S
Team Nissan
90 day: 156.46 mpg (US)

Number 7 - '15 VW e-Golf SEL
TEAM VW AUDI Group
90 day: 155.81 mpg (US)
Thanks: 3,388
Thanked 2,883 Times in 1,812 Posts
What piston engines are higher than 40% efficient in the real world? How long do they take to warm up? Can they have some sort of cogeneration cycle added on that significantly improves that?
__________________
Sincerely, Neil

http://neilblanchard.blogspot.com/
  Reply With Quote
Old 12-13-2010, 12:32 PM   #226 (permalink)
UFO
Master EcoModder
 
UFO's Avatar
 
Join Date: Sep 2010
Location: Denver, CO
Posts: 1,300

Colorado - '17 Chevrolet Colorado 4x4 LT
90 day: 23.07 mpg (US)
Thanks: 315
Thanked 178 Times in 138 Posts
Quote:
Originally Posted by NeilBlanchard View Post
What piston engines are higher than 40% efficient in the real world? How long do they take to warm up? Can they have some sort of cogeneration cycle added on that significantly improves that?
hey, I can answer that:

DIESELS!

Brake specific fuel consumption - Wikipedia, the free encyclopedia
__________________
I'm not coasting, I'm shifting slowly.
  Reply With Quote
Old 12-13-2010, 02:19 PM   #227 (permalink)
Master EcoModder
 
NeilBlanchard's Avatar
 
Join Date: May 2008
Location: Maynard, MA Eaarth
Posts: 7,873

Mica Blue - '05 Scion xA RS 2.0
Team Toyota
90 day: 42.48 mpg (US)

Forest - '15 Nissan Leaf S
Team Nissan
90 day: 156.46 mpg (US)

Number 7 - '15 VW e-Golf SEL
TEAM VW AUDI Group
90 day: 155.81 mpg (US)
Thanks: 3,388
Thanked 2,883 Times in 1,812 Posts
What is the most efficient diesel engine?

Obviously, biodiesel would avoid the massive penalty of wasting the majority of energy; because it is short-cycled energy and since it is renewable, it doesn't upset the balance of carbon in the atmosphere.
__________________
Sincerely, Neil

http://neilblanchard.blogspot.com/
  Reply With Quote
Old 12-13-2010, 08:13 PM   #228 (permalink)
Master EcoModder
 
Join Date: Apr 2010
Location: belgium, wi
Posts: 262

Bus - '94 Ford School Bus huge

Stupid - '01 Chevy Blazer LS
90 day: 21.38 mpg (US)

hawk - '00 Honda Superhawk
Thanks: 2
Thanked 24 Times in 19 Posts
Neil, do you refuse to read the links provided?
  Reply With Quote
Old 12-13-2010, 09:00 PM   #229 (permalink)
Master EcoModder
 
NeilBlanchard's Avatar
 
Join Date: May 2008
Location: Maynard, MA Eaarth
Posts: 7,873

Mica Blue - '05 Scion xA RS 2.0
Team Toyota
90 day: 42.48 mpg (US)

Forest - '15 Nissan Leaf S
Team Nissan
90 day: 156.46 mpg (US)

Number 7 - '15 VW e-Golf SEL
TEAM VW AUDI Group
90 day: 155.81 mpg (US)
Thanks: 3,388
Thanked 2,883 Times in 1,812 Posts
Nope, just missed it...

So, the VW TDI V8 (?) and the Audi TDI are most efficient car engines, then? Do diesels have Start/Stop tech?

Do the EPA rating for diesels take into account the higher BTU's per gallon of diesel?
__________________
Sincerely, Neil

http://neilblanchard.blogspot.com/
  Reply With Quote
Old 12-13-2010, 09:16 PM   #230 (permalink)
Master EcoModder
 
Join Date: Apr 2010
Location: belgium, wi
Posts: 262

Bus - '94 Ford School Bus huge

Stupid - '01 Chevy Blazer LS
90 day: 21.38 mpg (US)

hawk - '00 Honda Superhawk
Thanks: 2
Thanked 24 Times in 19 Posts
So, if the EPA uses mpg for both, but uses mpge for electric, one could conclude that they do not account for the energy density difference. That is their efficiency at constant operation, not using engine stop/start tech.

  Reply With Quote
Reply  Post New Thread


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Discussion on tire efficiency Ernie Rogers General Efficiency Discussion 69 12-27-2014 02:17 PM
The Easy Leg: Vehicle Efficiency natefish Off-Topic Tech 17 05-19-2010 05:52 PM
Vehicle Efficiency Improvements SVOboy EcoModder Blog Discussion 24 12-07-2009 11:19 PM
Worldís cleanest internal combustion engines? blueflame EcoModding Central 6 02-28-2009 09:13 PM
Low-Drag Trucks: Aerodynamic Improvements & Flow Control System Boost Fuel Efficiency OokiiMamoru Aerodynamics 5 06-16-2008 12:38 AM



Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com