Aeromod nissan leaf improved aerodynamics increased range

[knightmb]

It looks to me, a better aero mod to start would be to fill in the holes where the fog lights sit. Those 2 sit recessed in the front like a scoop. Certainly that doesn't help the aero of the vehicle? The air intake, while it makes sense why it needs to be there, I wonder if it was smoothed out in shape and maybe still had tiny holes to let some air in to prevent the engine area from being completely air restricted if that would help? Those are simply enough I might try it myself.

 

[NeilBlanchard]

There are two sources of aero drag:

1) Shape drag

2) Detail drag

Shape drag is the lion's share - probably at least 75% of the total.

Most of the shape drag comes at the back of the car, and the wheels and the wheel openings also are important. The spinning wheels are moving forward at 2X the speed that the car is moving.

The underside of the Leaf is already pretty good for detail drag. Cooling system drag is also pretty good, though ideally, there would be a thermally controlled shutter (like there is on the e-Golf).

Here's information on shape drag: http://ecomodder.com/forum/showthre...ne-tool-view-streamlined-extension-21952.html

Here's a list of aero mods: http://ecomodder.com/forum/showthread.php/list-aero-mods-you-can-do-your-vehicle-83.html

 

[minispeed]

There are two sources of aero drag:

1) Shape drag

2) Detail drag

Shape drag is the lion's share - probably at least 75% of the total.

Most of the shape drag comes at the back of the car, and the wheels and the wheel openings also are important. The spinning wheels are moving forward at 2X the speed that the car is moving.

The underside of the Leaf is already pretty good for detail drag. Cooling system drag is also pretty good, though ideally, there would be a thermally controlled shutter (like there is on the e-Golf).

Here's information on shape drag: http://ecomodder.com/forum/showthre...ne-tool-view-streamlined-extension-21952.html

Here's a list of aero mods: http://ecomodder.com/forum/showthread.php/list-aero-mods-you-can-do-your-vehicle-83.html

So who's going to be the first to do a boat tail? I've been thinking of a partial kamm back but since my wife has liberated the leaf from me most days now I doubt she'll allow that.

 

[Brenthasty]

what are some good boat tail ideas that do not block access to the trunk?

Im thinking one that floats near the car but is not attached to it, that plugs into my reciever hitch.

 

[NeilBlanchard]

I think a Kamm back is much more practical and easier to build than a (full) boattail. Unfortunately, my spouse would not stand for me doing what I did to my Scion xA: http://ecomodder.com/forum/showthread.php/scion-xa-aero-mods-2969.html

 

[Arlington]

It looks to me, a better aero mod to start would be to fill in the holes where the fog lights sit. Those 2 sit recessed in the front like a scoop. Certainly that doesn't help the aero of the vehicle? The air intake, while it makes sense why it needs to be there, I wonder if it was smoothed out in shape and maybe still had tiny holes to let some air in to prevent the engine area from being completely air restricted if that would help? Those are simply enough I might try it myself.

I wonder, though if the dead space at the front of the fog lights is dead enough that it forms a dam anyway.

This also raises the question of how big a difference it makes when closing the lower grill to use coroplast (thin plastic that leaves it dammed but indented) versus a built-up-flush foam. I've got plenty of black coroplast at home and am ready to block the air for the Boston winter (Nov 1 to April 1). Any thoughts on "how flush" to be?

Also what's the verdict on gas pods (little fins on the top of the car to match the integrated fins on the underside and at the base of the dash). Clearly Nissan believes fins work, so why not carry them further: taller beneath the windshield and also along the ridges of the roof?

 

[knightmb]

It looks to me, a better aero mod to start would be to fill in the holes where the fog lights sit. Those 2 sit recessed in the front like a scoop. Certainly that doesn't help the aero of the vehicle? The air intake, while it makes sense why it needs to be there, I wonder if it was smoothed out in shape and maybe still had tiny holes to let some air in to prevent the engine area from being completely air restricted if that would help? Those are simply enough I might try it myself.

I wonder, though if the dead space at the front of the fog lights is dead enough that it forms a dam anyway.

It will with enough air pressure, but it still takes energy to "hold" that air into place and more energy for more air to bounce around it. You can get the same effect by holding your hand into a cup shape and dipping into fast moving air out the window while driving. You can feel the force it takes to hold your hand in place against the fast moving air, so the same effect is being felt at the front of the car on both sides.

 

[Arlington]

It will with enough air pressure, but it still takes energy to "hold" that air into place and more energy for more air to bounce around it. You can get the same effect by holding your hand into a cup shape and dipping into fast moving air out the window while driving. You can feel the force it takes to hold your hand in place against the fast moving air, so the same effect is being felt at the front of the car on both sides.

So you'd recommend that while I'm at it (putting whatever coroplast or gaffer's tape over the lower grill for the winter) I should also put plugs in the fog lights (like maybe wedging in a cylindrical chunk of styrofoam?)

 

[knightmb]

It will with enough air pressure, but it still takes energy to "hold" that air into place and more energy for more air to bounce around it. You can get the same effect by holding your hand into a cup shape and dipping into fast moving air out the window while driving. You can feel the force it takes to hold your hand in place against the fast moving air, so the same effect is being felt at the front of the car on both sides.

So you'd recommend that while I'm at it (putting whatever coroplast or gaffer's tape over the lower grill for the winter) I should also put plugs in the fog lights (like maybe wedging in a cylindrical chunk of styrofoam?)

I was actually thinking the same thing for mine, at least something clear that can fit over the gap (because I still use my fog lights, put some high power LED bulbs in place of the old bulbs) I was looking at either some clear carbon sheet, but I haven't found an easy way to attach it without drilling holes into the bumper. I know the carbon sheet can be formed with heat into shapes, but have not experimented enough yet but in theory some very nice form fitting clear sheets could be created this way to slide right into the socket.

 

[Arlington]

Well the results are in, almost a full 1 mile more per KWH in my Nissan Leaf. Up from an average of 3.9 to 4.8 M/Kwh.

This was achieved by deleting the mud flaps, flipping the mudflaps from side to side and reattaching them in front of the wheels to aeromod and deflect the wind off the cheek of the tires. Along with a partial grille block and licence plate relocation. We placed the licence over the inlet left in the aerodynamic grill block, this serves to shed the wind more cleanly and block direct entrance of particles, bugs, rain ect directly into the grill and radiators. We run the tires at full sidewall pressure 45psi.

These simple improvements to the aerodynamics of the nissan leaf have added 20% in efficiency and range!
[youtube][/youtube]

Could you repost the link to the youtube video?

I'm highly likely to try blocking the lower grille, probably with styrofoam behind/building up to a coroplast veneer to make a smooth, flush facing, and then (somehow) attaching it with zip ties so I have the option of taking it out, which I would do either outside of cold season (which ends April 1 and resumes Nov 1) or only during "hot" season (really just June 15 to Sep 15 here in Boston)

 

[Arlington]

Anyone tried a long segment of a foam like
http://www.rockler.com/fastcap-kaizen-tool-storage-foam

To block their grille? It seems like building out from the grille to be near-flush with the license plate is kind of key if we're worried about pockets of pressurized air (as we are with the recessed fog lights)

 

[knightmb]

Anyone tried a long segment of a foam like
http://www.rockler.com/fastcap-kaizen-tool-storage-foam

To block their grille? It seems like building out from the grille to be near-flush with the license plate is kind of key if we're worried about pockets of pressurized air (as we are with the recessed fog lights)

It looks handy, will it hold up to sunlight, rain, etc.?

 

[Arlington]

I installed a black coroplast dam flush with the chrome trim and behind the front license plate covering the whole lower front air intake. The coroplast is attached by Velcro to styrofoam spacer blocks that I had zip tied to the grille to support the coroplast from behind.


Was looking for a setup that would be workable on a leased car (I happen to own used) and leave no marks when I take it out when warm weather returns.

No data yet-- mostly just happy that it appears stable at 70 mph.

 

[knightmb]

I installed a black coroplast dam flush with the chrome trim and behind the front license plate covering the whole lower front air intake. The coroplast is attached by Velcro to styrofoam spacer blocks that I had zip tied to the grille to support the coroplast from behind.


Was looking for a setup that would be workable on a leased car (I happen to own used) and leave no marks when I take it out when warm weather returns.

No data yet-- mostly just happy that it appears stable at 70 mph.

Nice! At that speed, does the car sound more quiet, more noisy, no difference in the front? Do you notice a big reduction in RAM air settings (little or no air entering through the vents when moving fast)?

 

[Arlington]

^ Now that you mention it, I would say it was quieter, but I didn't appreciate it because I was actually straining to hear new/extra noises of failure/detachment which never materialized.

Not thinking clearly (or at all) about turbulence noise at the time, my thoughts were that I was disappointed at how unusually quiet it was. So for friction noise, at least, we can rule out confirmation bias ;-) and say it likely reduced highway noise.

 

[Durandal]

So it's a year later, is there a final verdict from those who tried these mods?

 

[Brenthasty]

http://ecomodder.com/forum/em-fuel-log.php?vehicleid=9542

Long term results are a 50% improvement!

This make a big difference on long road trips .
Reduces time spent at Quick Charge stations .
Reduces loss of battery capacity over time due to reduced sustained power draw from the traction pack.

Had you tried it a year ago you would already know....

 

[NeilBlanchard]

Do you have pictures of all the mods posted? I am curious to see if there are some that I missed.

 

[Durandal]

Very cool. I intend on driving for about 2 weeks to establish a baseline of average miles per KWh, which as of my short 4 days of driving my Leaf has been 4.2 miles, then I will delete mudflaps to see what happens for 1 week, if that improves mileage, then I will reverse the mudflaps for 1 week to get an average usage on that. I've been doing gasoline hypermiling for some time, so my driving skill "improvements" over that period of time shouldn't make an impact.

Although I could just use Leaf Spy and do an A to B test on the same day that I remove and/or swap the position of them on the same stretch of flat highway at the same speed to see how much the draw is, but I believe you. If you look at the original Honda Insight, you can see that they do the reverse flaps at the front.

https://upload.wikimedia.org/wikipedia/commons/c/c9/HondaInsight.jpg

I bet having the rear wheel well covered like the Insight would make an improvement as well, although at the impact of styling.

 

[Brenthasty]

Since images are wonky to attach in this forum

You all can follow this link to view them on my blog:

http://fireplacefurnaces.blogspot.com/2016/03/aeromodding-nissan-leaf-increased-range.html?m=1