First Electric van boat tail

[JohnForde]

All done including lights. slopes are 11 -12 degrees and 86 " L. Wake area width is 48"

I will test tomorrow. Here are pics.

[JohnForde]

Finished tail:
84"L
11-12 degrees
66" behind the bumper
Wake area 48"W x 58"H, Floor @ 33" above ground
Stock Zevo 9'H x 7'W.
Stock Avg power at 63 mph = 35 Kw

Tested today with VGs. 30 miles @ 63 mph = 38Kw
Removed VGs, 50 miles at 63 mph =35 Kw.

Disappointed but that's science!

Tomorrow I will finally have an observer and do tuft tests.

[freebeard]

Have you reviewed the thread linked at Permalink #125?

[JohnForde]

Originally Posted by freebeard

Have you reviewed the thread linked at Permalink #125?

Thank you FreeBeard! I am ready to buy the Perfect Prime digital pressure sensor and pitot tube at Amazon. I am having a hard time understanding/finding pressure disks. The inexpensive ones have 2 electric leads. I assume I need an air tube. is a better search term "Pneumatic pressure sensing disk"?

Scanivalve and ARC list many products and no prices.

Can you point me to where I can buy one easily? Big Box store? Amazon? EBay?

Thanks FB!

JF

[freebeard]

Can you point me to where I can buy one easily? Big Box store? Amazon? EBay?

Sorry. I'm strictly a [local] brick-and-mortar shopper.

The subject of sensor pucks was addressed by [banned] member Julian Edgar in hecomodder.com/forum/showthread.php/20-monitoring-air-fuel-ratios-std-wideband-sensor-5204.html

Here he promoted a book (see Section Two) ecomodder.com/forum/showthread.php/new-amateur-aerodynamics-book-25452.html

Notice Permalink #6 there. After you conclude your current experiment we can talk about this:

[JohnForde]

I have 3 of 4 but do not know where to find the pressure sensing disc/patch. Anyone have ideas? Thanks JF

[Vman455]

Originally Posted by JohnForde

I have 3 of 4 but do not know where to find the pressure sensing disc/patch. Anyone have ideas? Thanks JF

You won't find these retail; you have to call Scanivalve and talk to a salesperson. They were inexpensive, maybe $10 or $12 per. Let me check the garage tomorrow, I might have some extras laying around--you're welcome to them if so. These along with tufts are very useful:

[JohnForde]

Originally Posted by Vman455

You won't find these retail; you have to call Scanivalve and talk to a salesperson. They were inexpensive, maybe $10 or $12 per. Let me check the garage tomorrow, I might have some extras laying around--you're welcome to them if so. These along with tufts are very useful:

Thank you VMan! I will DM my email address to you. JF

[aerohead]

Originally Posted by JohnForde

Thank you FreeBeard! I am ready to buy the Perfect Prime digital pressure sensor and pitot tube at Amazon. I am having a hard time understanding/finding pressure disks. The inexpensive ones have 2 electric leads. I assume I need an air tube. is a better search term "Pneumatic pressure sensing disk"?

Scanivalve and ARC list many products and no prices.

Can you point me to where I can buy one easily? Big Box store? Amazon? EBay?

Thanks FB!

JF

The Pitot tube and static pressure puck / data-logger, may require different diameter Tygon tubing sizes.
And if you're going to measure velocity profiles at your static pressure measuring locations, you'll need some sort of manometer or a MAGNEHELIC, ,probably zero-to-3-inches of water column equivalency, depending on the unit of measure you choose. Dwyer will have whatever you want.
Sounds like VMan455 has you covered on 'pucks.'

[JohnForde]

Rainy here so with time on my hands I get wordier and my posts longer.

Amazon is selling me these 3 in the photo: Digital Manometer, Pitot & tubing. VMan455 is generously sending me pucks.

Tomorrow after the rain I shouid be able to do my first tuft test. Chaotic yarn will explain my lack of drag reduction. Attached flow would be perplexing.

In the mean time I have 2 theories: 1. Cuff needs smoothing, and 2. Corners leak to much air weakening sequestration. I will work on both today or tomorrow between rain showers. Then tuft test. Pressure test will have to wait a week.

I really am kind f surprised to see no improvement with 3 huge 11 degree slopes.

Thoughts anyone?