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9/17/2020 5:59:48 PM
Posted: 7/21/2008 2:06:35 PM EDT
[Last Edit: 7/21/2008 2:09:00 PM EDT by Combat_Jack]
I another thread I posted that conservation is an untapped resource.  I noted that WalMart has hired a consultancy to help them double their mileage.

Here is a link to the study that resulted and here is a link to a news article about the project.
Link Posted: 7/21/2008 2:26:02 PM EDT
Wow, hot topic.  I thought all the people who like to imply fabrication and ignorance on my part would show up.
Link Posted: 7/21/2008 3:44:42 PM EDT
Im not reading all that you need cliff notes
Link Posted: 7/21/2008 3:52:37 PM EDT
Looks like they may be trying to turn semi tractors into road versions of rail prime movers.
The abstract talks about stringing multiple trailers together (a la Aussie land trains) and the associated articles speaks of diesel-electric hybrids which I have been saying for a loooooong time is the way to go in hybrid energy.
Link Posted: 7/21/2008 3:53:39 PM EDT
By building lighter, more aerodynamic trucks it is possible to build 12+ MPG semis at no increase in price.  Further, towing two trailers is 15-35% more efficient than driving two trucks for the same purpose.

Taking these steps will cut truckers fuel bill in half and cut US diesel consumption by up to six percent with no change in lifestyle.
Link Posted: 7/21/2008 3:54:27 PM EDT

Originally Posted By ziarifleman:
Looks like they may be trying to turn semi tractors into road versions of rail prime movers.
The abstract talks about stringing multiple trailers together (a la Aussie land trains) and the associated articles speaks of diesel-electric hybrids which I have been saying for a loooooong time is the way to go in hybrid energy.


That pretty much sums it up, as well.
Link Posted: 7/21/2008 3:55:37 PM EDT

Originally Posted By Combat_Jack:
By building lighter, more aerodynamic trucks it is possible to build 12+ MPG semis at no increase in price.  Further, towing two trailers is 15-35% more efficient than driving two trucks for the same purpose.

Taking these steps will cut truckers fuel bill in half and cut US diesel consumption by up to six percent with no change in lifestyle.


Not trying to be argumentative, but why aren't trucking companies and manufacturers doing this now?
Link Posted: 7/21/2008 3:55:44 PM EDT
Unpossible.  Wal-Mart is run by the Devil and his minions, and only government bureaucracy, not capitalism, can help solve our energy issues.
Link Posted: 7/21/2008 3:55:45 PM EDT

Originally Posted By Combat_Jack:
By building lighter, more aerodynamic trucks it is possible to build 12+ MPG semis at no increase in price.


If that was true, they'd be doing it.
Link Posted: 7/21/2008 3:57:52 PM EDT

Originally Posted By jnojr:

Originally Posted By Combat_Jack:
By building lighter, more aerodynamic trucks it is possible to build 12+ MPG semis at no increase in price.


If that was true, they'd be doing it.


They are.  Pick up a copy of Fleet magazine.  It's all they talk about.
Link Posted: 7/21/2008 3:59:05 PM EDT
Impossible unless you have a hydrogen generator under the hood
Link Posted: 7/21/2008 3:59:35 PM EDT

Originally Posted By ampn:

Originally Posted By Combat_Jack:
By building lighter, more aerodynamic trucks it is possible to build 12+ MPG semis at no increase in price.  Further, towing two trailers is 15-35% more efficient than driving two trucks for the same purpose.

Taking these steps will cut truckers fuel bill in half and cut US diesel consumption by up to six percent with no change in lifestyle.


Not trying to be argumentative, but why aren't trucking companies and manufacturers doing this now?


Aerodynamic cab designs were pioneered in the 1970's and they still aren't universal.  But that holds true for lots of things.  Why not?

Try running it by an old school trucker.  Lots of people don't want to change.  Hell, my dad owns three semis and 20 smaller trucks and he doesn't have a clue how to get better mileage out of them.
Link Posted: 7/21/2008 4:00:40 PM EDT

Originally Posted By AssaultRifler:
Impossible unless you have a hydrogen generator under the hood


The funny thing is that there are test engines built to run diesel and hydrogen (40/60) and they seem to have a lot of promise.

Of course, there is a lot more to the story than just running hydrogen to the engine, but I don't want to kill anyones dreams.
Link Posted: 7/21/2008 4:01:41 PM EDT
I put a magnet on my fuel line, and it aligns the molecules for more complete combustion. I now get 145mg out of my '02 Chevy crew Duramax. I expect it to improve when I unhook the 35,000lb trailer.
Link Posted: 7/21/2008 4:03:26 PM EDT
[Last Edit: 7/21/2008 4:04:31 PM EDT by Combat_Jack]

Originally Posted By jnojr:

Originally Posted By Combat_Jack:
By building lighter, more aerodynamic trucks it is possible to build 12+ MPG semis at no increase in price.


If that was true, they'd be doing it.


They are.  Read the news article.

Do any of you read?  I put it right in front of you!



But one division says it is already well under way to meet its goals. Wal-Mart's fleet of about 7,200 semitractor-trailer trucks is already about 15 percent more fuel efficient and the company knows what changes it needs to make to meet a target of 25 percent by late next year.


Link Posted: 7/21/2008 4:03:58 PM EDT

   Lowering the floor of the trailers might seem like a good idea but it would create problems loading and unloading them. Most docks that trailers load from are at a uniform height.

Link Posted: 7/21/2008 4:05:30 PM EDT

Originally Posted By ampn:

Originally Posted By Combat_Jack:
By building lighter, more aerodynamic trucks it is possible to build 12+ MPG semis at no increase in price.  Further, towing two trailers is 15-35% more efficient than driving two trucks for the same purpose.

Taking these steps will cut truckers fuel bill in half and cut US diesel consumption by up to six percent with no change in lifestyle.


Not trying to be argumentative, but why aren't trucking companies and manufacturers doing this now?


Truckers, other than the big fleets, will not buy "ugly" aero cab trucks that they cant hang a huge chrome Texas bumper on, 12" Bull Hauler straights, and a metric ton of chrome.

At least, that is how I understand it. Image is a huge thing for a truck driver. I think it was Dusty_C who rolls his eyes when they gripe about fuel prices but brag on the $5k of chrome they just put on their extended hood Pete (aerodynamics of a fucking brick).
Link Posted: 7/21/2008 4:09:59 PM EDT
[Last Edit: 7/21/2008 4:10:13 PM EDT by pdg45acp]

Originally Posted By Combat_Jack:

Originally Posted By AssaultRifler:
Impossible unless you have a hydrogen generator under the hood


The funny thing is that there are test engines built to run diesel and hydrogen (40/60) and they seem to have a lot of promise.

Of course, there is a lot more to the story than just running hydrogen to the engine, but I don't want to kill anyones dreams.



My oldest son is an Engineer for Bosch in their Common Rail Diesel Program. He thinks you're pretty funny.

If you are going to efficiently use hydrogen as a propellant in a wheeled vehicle you won't be doing it in a reciprocating engine. You'll be doing it in a electric car with a hydrogen fuel cell.
Link Posted: 7/21/2008 4:13:27 PM EDT
Sterling has dual fuel trucks on the road now.  
Link Posted: 7/21/2008 4:21:30 PM EDT

Originally Posted By pdg45acp:

Originally Posted By Combat_Jack:

Originally Posted By AssaultRifler:
Impossible unless you have a hydrogen generator under the hood


The funny thing is that there are test engines built to run diesel and hydrogen (40/60) and they seem to have a lot of promise.

Of course, there is a lot more to the story than just running hydrogen to the engine, but I don't want to kill anyones dreams.



My oldest son is an Engineer for Bosch in their Common Rail Diesel Program. He thinks you're pretty funny.

If you are going to efficiently use hydrogen as a propellant in a wheeled vehicle you won't be doing it in a reciprocating engine. You'll be doing it in a electric car with a hydrogen fuel cell.




<------------- has a Bosch HPCR system in his truck.
Link Posted: 7/21/2008 4:31:15 PM EDT

Originally Posted By ampn:

Originally Posted By Combat_Jack:
By building lighter, more aerodynamic trucks it is possible to build 12+ MPG semis at no increase in price.  Further, towing two trailers is 15-35% more efficient than driving two trucks for the same purpose.

Taking these steps will cut truckers fuel bill in half and cut US diesel consumption by up to six percent with no change in lifestyle.


Not trying to be argumentative, but why aren't trucking companies and manufacturers doing this now?


in nor particular order

#1 is replacement cost of current fleet.. they just cant afford to get rid of trucks that are anything close to new.. keep in mind that class 8's under the right conditions will/can run a millions miles..

#2 Double or triple trailers are not legal in certain states.. I believe here in VA that you can have 28' doubles on the interstate, but not on any other roads..

#3 Alot of companies replaced there trucks before either 2007 or 2008 to not have to spend the money for the updated diesel engines required by the EPA.. IIRC the cost of the newer engine was +$6k (maybe as much as $10k over the previous engine..)



Brian
Link Posted: 7/21/2008 4:31:42 PM EDT
I attended an SAE presentation during college (~'93) about the MPG improvements from better aerodynamics on semis.  They were getting ~9-10mpg on fully loaded trucks by skirting the bottom of the trailer, using a 'ball/socket' joint between the cab/trailer and using a teardrop on the back of the trailer.  Obviously it cost money to do these mods but given the price of fuel today it wouldn't surprise me to see these mods going down the road.....  The biggest problem was maintaining the 'tight' fit of the mods over time.

Brian
Link Posted: 7/21/2008 4:32:12 PM EDT

Originally Posted By pdg45acp:

Originally Posted By Combat_Jack:

Originally Posted By AssaultRifler:
Impossible unless you have a hydrogen generator under the hood


The funny thing is that there are test engines built to run diesel and hydrogen (40/60) and they seem to have a lot of promise.

Of course, there is a lot more to the story than just running hydrogen to the engine, but I don't want to kill anyones dreams.



My oldest son is an Engineer for Bosch in their Common Rail Diesel Program. He thinks you're pretty funny.

If you are going to efficiently use hydrogen as a propellant in a wheeled vehicle you won't be doing it in a reciprocating engine. You'll be doing it in a electric car with a hydrogen fuel cell.


Please thank your son for me.  So many don't understand volumetric efficiency,  stoichiometric ratios, friction loss, the conservation of energy and a ton of other things involved with this stuff.  A conventional reciprocating engine is nearing its limits as far as mileage goes The cheapest and fastest way to better efficiency right now is through aerodynamic changes.
Link Posted: 7/21/2008 4:32:27 PM EDT

Originally Posted By NoStockBikes:
I put a magnet on my fuel line, and it aligns the molecules for more complete combustion. I now get 145mg out of my '02 Chevy crew Duramax. I expect it to improve when I unhook the 35,000lb trailer.


Was that with the tail gate up or down?  Just curious...  

Brian
Link Posted: 7/21/2008 4:40:11 PM EDT

Originally Posted By thatguy:

Originally Posted By ampn:

Originally Posted By Combat_Jack:
By building lighter, more aerodynamic trucks it is possible to build 12+ MPG semis at no increase in price.  Further, towing two trailers is 15-35% more efficient than driving two trucks for the same purpose.

Taking these steps will cut truckers fuel bill in half and cut US diesel consumption by up to six percent with no change in lifestyle.


Not trying to be argumentative, but why aren't trucking companies and manufacturers doing this now?


in nor particular order

#1 is replacement cost of current fleet.. they just cant afford to get rid of trucks that are anything close to new.. keep in mind that class 8's under the right conditions will/can run a millions miles..

#2 Double or triple trailers are not legal in certain states.. I believe here in VA that you can have 28' doubles on the interstate, but not on any other roads..

#3 Alot of companies replaced there trucks before either 2007 or 2008 to not have to spend the money for the updated diesel engines required by the EPA.. IIRC the cost of the newer engine was +$6k (maybe as much as $10k over the previous engine..)



Brian


I would expect that independents with little cash on hand would have trouble making the necessary investment . . .
Link Posted: 7/21/2008 4:43:46 PM EDT

Originally Posted By Combat_Jack:

Originally Posted By jnojr:

Originally Posted By Combat_Jack:
By building lighter, more aerodynamic trucks it is possible to build 12+ MPG semis at no increase in price.


If that was true, they'd be doing it.


They are.  Pick up a copy of Fleet magazine.  It's all they talk about.


Your original statement strongly implied that "it could be done", not that it was being done.
Link Posted: 7/21/2008 4:50:19 PM EDT

Originally Posted By blackeye:
   Lowering the floor of the trailers might seem like a good idea but it would create problems loading and unloading them. Most docks that trailers load from are at a uniform height.



Fortunately, many of those are built with a combination of a lowered pavement (ramp down toward the dock) and a raised dock.  Filling in the lowering ramp would raise the truck sufficiently in a lot of cases.
Link Posted: 7/21/2008 4:56:31 PM EDT

Originally Posted By thatguy:

Originally Posted By NoStockBikes:
I put a magnet on my fuel line, and it aligns the molecules for more complete combustion. I now get 145mg out of my '02 Chevy crew Duramax. I expect it to improve when I unhook the 35,000lb trailer.


Was that with the tail gate up or down?  Just curious...  

Brian


sounds like he had it up.  everybody knows that you get 50+ MORE better mileage with the tailgate down.
Link Posted: 7/21/2008 5:36:57 PM EDT
Trucks are already dangerous enough without adding another entire trailer to them.  There needs to be fewer trucks on the road, not more.  

Railroads are a much better way in the long term.  Much more efficient, truck can never be as efficient as railroads in tons x miles/fuel used.  And they operate on their own private right of way, which limits their interaction with the public and is much safer overall.  

Screw trucks.  I hate getting run off the road by them in bad weather.
Link Posted: 7/21/2008 5:38:09 PM EDT

Originally Posted By TheKill:
Trucks are already dangerous enough without adding another entire trailer to them.  There needs to be fewer trucks on the road, not more.  

Railroads are a much better way in the long term.  Much more efficient, truck can never be as efficient as railroads in tons x miles/fuel used.  And they operate on their own private right of way, which limits their interaction with the public and is much safer overall.  

Screw trucks.  I hate getting run off the road by them in bad weather.


You gonna get raped.
Link Posted: 7/21/2008 6:18:27 PM EDT

Originally Posted By Keith_J:

Originally Posted By TheKill:
Trucks are already dangerous enough without adding another entire trailer to them.  There needs to be fewer trucks on the road, not more.  

Railroads are a much better way in the long term.  Much more efficient, truck can never be as efficient as railroads in tons x miles/fuel used.  And they operate on their own private right of way, which limits their interaction with the public and is much safer overall.  

Screw trucks.  I hate getting run off the road by them in bad weather.


You gonna get raped.


My dad has been an OTR trucker for much of his life.  I've been a railroader for 14 years.  I've heard all the arguments.  None of them are effective.
Link Posted: 7/21/2008 8:36:49 PM EDT

Originally Posted By jnojr:

Originally Posted By Combat_Jack:

Originally Posted By jnojr:

Originally Posted By Combat_Jack:
By building lighter, more aerodynamic trucks it is possible to build 12+ MPG semis at no increase in price.


If that was true, they'd be doing it.


They are.  Pick up a copy of Fleet magazine.  It's all they talk about.


Your original statement strongly implied that "it could be done", not that it was being done.


It isn't, to the degree that appears possible.


Originally Posted By ScrubJ:

Please thank your son for me.  So many don't understand volumetric efficiency,  stoichiometric ratios, friction loss, the conservation of energy and a ton of other things involved with this stuff.  A conventional reciprocating engine is nearing its limits as far as mileage goes The cheapest and fastest way to better efficiency right now is through aerodynamic changes.


I don't claim to understand those things, only that it is being done and there are reportedly benefits.

FWIW, this study straight up said that working to get more efficiency from the engine was a waste of time.


Originally Posted By Keith_J:

Originally Posted By TheKill:
Trucks are already dangerous enough without adding another entire trailer to them.  There needs to be fewer trucks on the road, not more.  

Railroads are a much better way in the long term.  Much more efficient, truck can never be as efficient as railroads in tons x miles/fuel used.  And they operate on their own private right of way, which limits their interaction with the public and is much safer overall.  

Screw trucks.  I hate getting run off the road by them in bad weather.


You gonna get raped.


I'll help with the raping!  I like rail as much as the next guy, but it has serious disadvantages, and this technology (dual trailers) will take trucks off the road, by requiring fewer trucks to move the same cargo.
Link Posted: 7/22/2008 1:08:28 PM EDT
Bump.
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