Plot of Engine Speed vs. Fuel Consumption

#11

On Tue, 15 Apr 2008 04:06:26 -0700 (PDT), ACAR
<dimndsonmywndshld (AT) yahoo (DOT) com> wrote:

Quote:

On Apr 12, 4:49 pm, ecarecar <ecare... (AT) yahoo (DOT) com> wrote:
I am looking for a plot of engine speed vs. fuel consumption. Is one
available anywhere? I am not at all picky about what specific engine.

I suspect Universities that compete in building very fuel efficient
vehicles (esp. hybrids) would have this information available to the
public.

Marine applications may be a source, too.

Maybe Briggs & Stratton has that info. for their lawn mower engines.

Here is a plot of Brake Specific Fuel Consumption vs. rpm for a VW TDI
engine.

http://forums.tdiclub.com/showthread.php?t=208125

BSFC is the measure of how much fuel is being consumed per unit power
generated - a true fuel efficiency measurement. To get an absolute
fuel consumption rate, you could multiply the BSFC by power at a given
rpm. Of course this all assumes wide open throttle. If you are
running at a lower power setting, the absolute fuel consumption will
be lower. I would guess that BSFC might be higher or lower depending
on the way the engine is set up.

Maybe the OP could tell us exactly what he wants to know.

#12

"ecarecar" <ecarecar (AT) yahoo (DOT) com> wrote

<...>

Quote:

After years - literally YEARS - of searching, I found information that
served my purposes.

This will get you from 0 km/hr to 60 km/hr
http://www.jari.jp/pdf/rt2005/09Fu_eng.pdf

This will get you from 50 km/hr to 140 km/hr
http://www.greencarcongress.com/2006/05/fuel_consumptio.htm

The first, as you might have guess, is from Japan. The second is from
Germany.

This second link doesn't work for me. Even after correcting obvious
spelling errors. Could you try again?
Thanks.

--
Graham W. www.gcw.org.uk Homebuilt Computer cooling. DIY projects
Wimborne. www.wessex-astro.org.uk Society website, meetings,
Dorset UK. location maps and future programs.

#13

"www.greencarcongress.com/2006/05/fuel_consumptio.html"

Graham (AT) home (DOT) invalid wrote:

Quote:

"ecarecar" <ecarecar (AT) yahoo (DOT) com> wrote in message
news:Cu6dnVZvAaOW1pjVnZ2dnUVZ_tajnZ2d (AT) centurytel (DOT) net...
...

After years - literally YEARS - of searching, I found information
that served my purposes.

This will get you from 0 km/hr to 60 km/hr
http://www.jari.jp/pdf/rt2005/09Fu_eng.pdf

This will get you from 50 km/hr to 140 km/hr
http://www.greencarcongress.com/2006/05/fuel_consumptio.htm

The first, as you might have guess, is from Japan. The second is
from Germany.

This second link doesn't work for me. Even after correcting obvious
spelling errors. Could you try again?
Thanks.

#14

Gordon McGrew wrote:

Quote:

On Tue, 15 Apr 2008 04:06:26 -0700 (PDT), ACAR
dimndsonmywndshld (AT) yahoo (DOT) com> wrote:

On Apr 12, 4:49 pm, ecarecar <ecare... (AT) yahoo (DOT) com> wrote:

I am looking for a plot of engine speed vs. fuel consumption. Is one
available anywhere? I am not at all picky about what specific engine.

I suspect Universities that compete in building very fuel efficient
vehicles (esp. hybrids) would have this information available to the
public.

Marine applications may be a source, too.

Maybe Briggs & Stratton has that info. for their lawn mower engines.

Here is a plot of Brake Specific Fuel Consumption vs. rpm for a VW TDI
engine.

http://forums.tdiclub.com/showthread.php?t=208125

BSFC is the measure of how much fuel is being consumed per unit power
generated - a true fuel efficiency measurement. To get an absolute
fuel consumption rate, you could multiply the BSFC by power at a given
rpm. Of course this all assumes wide open throttle. If you are
running at a lower power setting, the absolute fuel consumption will
be lower. I would guess that BSFC might be higher or lower depending
on the way the engine is set up.

Maybe the OP could tell us exactly what he wants to know.

This is WOT? Therefore, it is also full throttle ignition advance?

The bottom of the curve is quite narrow.

#15

On Wed, 16 Apr 2008 17:46:40 -0400, ecarecar <ecarecar (AT) yahoo (DOT) com>
wrote:

Quote:

Gordon McGrew wrote:

On Tue, 15 Apr 2008 04:06:26 -0700 (PDT), ACAR
dimndsonmywndshld (AT) yahoo (DOT) com> wrote:

On Apr 12, 4:49 pm, ecarecar <ecare... (AT) yahoo (DOT) com> wrote:

I am looking for a plot of engine speed vs. fuel consumption. Is one
available anywhere? I am not at all picky about what specific engine.

I suspect Universities that compete in building very fuel efficient
vehicles (esp. hybrids) would have this information available to the
public.

Marine applications may be a source, too.

Maybe Briggs & Stratton has that info. for their lawn mower engines.

Here is a plot of Brake Specific Fuel Consumption vs. rpm for a VW TDI
engine.

http://forums.tdiclub.com/showthread.php?t=208125

BSFC is the measure of how much fuel is being consumed per unit power
generated - a true fuel efficiency measurement. To get an absolute
fuel consumption rate, you could multiply the BSFC by power at a given
rpm. Of course this all assumes wide open throttle. If you are
running at a lower power setting, the absolute fuel consumption will
be lower. I would guess that BSFC might be higher or lower depending
on the way the engine is set up.

Maybe the OP could tell us exactly what he wants to know.

This is WOT? Therefore, it is also full throttle ignition advance?
The bottom of the curve is quite narrow.

Well actually it is a diesel so there is no throttle (my bad) and no
ignition. What I should have said is that I assume this curve is for
maximum power setting.

Again, it is not clear exactly what you are trying to show/learn here.
For example, are you interested in fuel consumption at various engine
speeds or car speeds?

#16

On Apr 12, 4:49 pm, ecarecar <ecare... (AT) yahoo (DOT) com> wrote:

Quote:

I am looking for a plot of engine speed vs. fuel consumption. Is one
available anywhere? I am not at all picky about what specific engine.

By laws of aerodynamics, air drag is proportionate to the square of
the object's velocity. If the speed is doubled, then it requires a
quadrupled energy to overcome the drag. At the same time, the object
travels twice the distance. Spending four times the amount of energy
to propel the object twice the distance means the energy efficiency is
cut in half.

Likewise, if the object's velocity is trippled then energy efficiency
is reduced to one third.. and so on...

In automobile, rolling friction is also a factor but it's a linear
drag, while air drag is a quadratic drag. The combined result is
closer to the air drag only model.

In layman terms, if you've got a car that does 30 mpg at 60 mph, then
you can expect 15 mpg at 120 mph. It can be more or less, depending on
the efficiency of the engine's combustion chambers, and its own
internal friction at higher rpm

#17

"ecarecar" <ecarecar (AT) yahoo (DOT) com> wrote

Quote:

"www.greencarcongress.com/2006/05/fuel_consumptio.html"

Graham (AT) home (DOT) invalid wrote:

"ecarecar" <ecarecar (AT) yahoo (DOT) com> wrote in message
news:Cu6dnVZvAaOW1pjVnZ2dnUVZ_tajnZ2d (AT) centurytel (DOT) net...
...

After years - literally YEARS - of searching, I found information that
served my purposes.

This will get you from 0 km/hr to 60 km/hr
http://www.jari.jp/pdf/rt2005/09Fu_eng.pdf

This will get you from 50 km/hr to 140 km/hr
http://www.greencarcongress.com/2006/05/fuel_consumptio.htm

The first, as you might have guess, is from Japan. The second is from
Germany.

This second link doesn't work for me. Even after correcting obvious
spelling errors. Could you try again?
Thanks.

That works!! And so does the other one now if I edit an 'L' where needed.
It didn't work before.

Thanks again.

--
Graham W. www.gcw.org.uk Homebuilt Computer cooling. DIY projects
Wimborne. www.wessex-astro.org.uk Society website, meetings,
Dorset UK. location maps and future programs.

#18

Gordon McGrew wrote:

Quote:

On Wed, 16 Apr 2008 17:46:40 -0400, ecarecar <ecarecar (AT) yahoo (DOT) com
wrote:

Gordon McGrew wrote:

On Tue, 15 Apr 2008 04:06:26 -0700 (PDT), ACAR
dimndsonmywndshld (AT) yahoo (DOT) com> wrote:

On Apr 12, 4:49 pm, ecarecar <ecare... (AT) yahoo (DOT) com> wrote:

I am looking for a plot of engine speed vs. fuel consumption. Is one
available anywhere? I am not at all picky about what specific engine.

I suspect Universities that compete in building very fuel efficient
vehicles (esp. hybrids) would have this information available to the
public.

Marine applications may be a source, too.

Maybe Briggs & Stratton has that info. for their lawn mower engines.

Here is a plot of Brake Specific Fuel Consumption vs. rpm for a VW TDI
engine.

http://forums.tdiclub.com/showthread.php?t=208125

BSFC is the measure of how much fuel is being consumed per unit power
generated - a true fuel efficiency measurement. To get an absolute
fuel consumption rate, you could multiply the BSFC by power at a given
rpm. Of course this all assumes wide open throttle. If you are
running at a lower power setting, the absolute fuel consumption will
be lower. I would guess that BSFC might be higher or lower depending
on the way the engine is set up.

Maybe the OP could tell us exactly what he wants to know.

This is WOT? Therefore, it is also full throttle ignition advance?
The bottom of the curve is quite narrow.

Well actually it is a diesel so there is no throttle (my bad) and no
ignition. What I should have said is that I assume this curve is for
maximum power setting.

Again, it is not clear exactly what you are trying to show/learn here.
For example, are you interested in fuel consumption at various engine
speeds or car speeds?

I don't know which chart you mean. Not all the cars in the top chart at

www.greencarcongress.com/2006/05/fuel_consumptio.html

are diesel.

#19

bi241 (AT) scn (DOT) org wrote:

Quote:

On Apr 12, 4:49 pm, ecarecar <ecare... (AT) yahoo (DOT) com> wrote:

I am looking for a plot of engine speed vs. fuel consumption. Is one
available anywhere? I am not at all picky about what specific engine.

By laws of aerodynamics, air drag is proportionate to the square of
the object's velocity. If the speed is doubled, then it requires a
quadrupled energy to overcome the drag. At the same time, the object
travels twice the distance. Spending four times the amount of energy
to propel the object twice the distance means the energy efficiency is
cut in half.

Actually, it is a quadrupling of the force.

Quote:

Likewise, if the object's velocity is trippled then energy efficiency
is reduced to one third.. and so on...

In automobile, rolling friction is also a factor but it's a linear
drag, while air drag is a quadratic drag. The combined result is
closer to the air drag only model.

In layman terms, if you've got a car that does 30 mpg at 60 mph, then
you can expect 15 mpg at 120 mph. It can be more or less, depending on
the efficiency of the engine's combustion chambers, and its own
internal friction at higher rpm

#20

On Thu, 17 Apr 2008 21:51:12 -0400, ecarecar <ecarecar (AT) yahoo (DOT) com>
wrote:

Quote:

Gordon McGrew wrote:

On Wed, 16 Apr 2008 17:46:40 -0400, ecarecar <ecarecar (AT) yahoo (DOT) com
wrote:

Gordon McGrew wrote:

On Tue, 15 Apr 2008 04:06:26 -0700 (PDT), ACAR
dimndsonmywndshld (AT) yahoo (DOT) com> wrote:

On Apr 12, 4:49 pm, ecarecar <ecare... (AT) yahoo (DOT) com> wrote:

I am looking for a plot of engine speed vs. fuel consumption. Is one
available anywhere? I am not at all picky about what specific engine.

I suspect Universities that compete in building very fuel efficient
vehicles (esp. hybrids) would have this information available to the
public.

Marine applications may be a source, too.

Maybe Briggs & Stratton has that info. for their lawn mower engines.

Here is a plot of Brake Specific Fuel Consumption vs. rpm for a VW TDI
engine.

http://forums.tdiclub.com/showthread.php?t=208125

BSFC is the measure of how much fuel is being consumed per unit power
generated - a true fuel efficiency measurement. To get an absolute
fuel consumption rate, you could multiply the BSFC by power at a given
rpm. Of course this all assumes wide open throttle. If you are
running at a lower power setting, the absolute fuel consumption will
be lower. I would guess that BSFC might be higher or lower depending
on the way the engine is set up.

Maybe the OP could tell us exactly what he wants to know.

This is WOT? Therefore, it is also full throttle ignition advance?
The bottom of the curve is quite narrow.

Well actually it is a diesel so there is no throttle (my bad) and no
ignition. What I should have said is that I assume this curve is for
maximum power setting.

Again, it is not clear exactly what you are trying to show/learn here.
For example, are you interested in fuel consumption at various engine
speeds or car speeds?

I don't know which chart you mean. Not all the cars in the top chart at

www.greencarcongress.com/2006/05/fuel_consumptio.html

are diesel.

I was talking about the chart I linked to above:

http://forums.tdiclub.com/showthread.php?t=208125

(You have to page down a couple times to see it.)