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electric boost?

There are no end-on pictures of the "device" ....but if it is built like the "demonstration video" shows it, it is a single fan......and if so, I will stand on my original opinion....and if the tube size is around 3", there is no way the motor has much power....there isn't enough room....and if they have invented a way to create a spatial anomoly that allows 10 pounds in a 5 pound sack....I have a complete set of air pressure and velocity measurement tools....and experience using them....in other words unless I see that thing run on a test bed with my instruments and myself doing the measurement....its pure :bs:
 
MudDawg said:
There are no end-on pictures of the "device" ....but if it is built like the "demonstration video" shows it, it is a single fan......and if so, I will stand on my original opinion....and if the tube size is around 3", there is no way the motor has much power....there isn't enough room....and if they have invented a way to create a spatial anomoly that allows 10 pounds in a 5 pound sack....I have a complete set of air pressure and velocity measurement tools....and experience using them....in other words unless I see that thing run on a test bed with my instruments and myself doing the measurement....its pure :bs:
Click to expand...
How much does this thing weigh? add 20 lbs or so and there goes 1HP. And then, if this thing is pulling 50 amps consider the drag on the alternator. Result= no net gain considering you have to spend your time installing this thing. This thing is even worse than the "tornado" because it requires modification to install.
 
jeeperjohn said:
How much does this thing weigh? add 20 lbs or so and there goes 1HP. And then, if this thing is pulling 50 amps consider the drag on the alternator. Result= no net gain considering you have to spend your time installing this thing. This thing is even worse than the "tornado" because it requires modification to install.
Click to expand...
It is designed for operation only at WOT for 5 to 15 seconds only, so it pulls its power from the battery (according to the inventors web site, have you read the tech section of it yet?) and the alternator recharges the battery when it cuts off. It is like turning on the head lights and brakes for a few seconds load wise. You guys should really read their tech section. It is not full of BS, and everything they say in that section is sound hard science. I am an extreemly sceptical degreed Chemical Engineer with several DOE patents myself, and an old fart on top of it, and after reading all the tech section materials deep in there web site I was somewhat impressed.

I still think it is way overpriced, but I am a DIY engineer so I think most stuff is way overpriced anyway (LOL).

On the HP versus size issue, if it ran at 3500 rpm I would agree the diameter is too small, but these guys are cranking this thing up to 25,000 rpm which could pull that much hp (50 amps at 12 volts) in that small a space. It would need to be a precison instrument, extreemly well balanced (which cost a lot more). They list several reasons that it is designed to only run for 5 to 15 seconds at WOT. Overheating of the motor is one. Ineffectivness at other operating conditions is another (they even admit that), but it is designed only to boost peak WOT HP, nothing more. Note that it operates at WOT anywhere from 0 to max highway speed. In other words it claims it can give you a bit more HP from a dead stop at WOT take off, or help in passing.
 
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Sorry, but I found a complete lack of substantial hard data. A 25,000 rpm Brush commutated DC motor is not a modern marvel....I built slot car engines in the late 60's that turned more rpm, its a matter of commutator phasing, brush float and the ability to withstand the centrifugal and frictional forces...and my balancing station was a pair of razor blades...I really would like to see a parts diagram to know the mechanical configuration...the fan blade (from what can be seen in one picture) is not even a air foil design, and is straight edged...all bad news for a high rpm blade....i'll bet the thing goes into cavitation at the slightest resistance to air flow....and the design of the housing is very poor as design relates to fluid flow....thats it, i'm done with this one after my parting shot.....PT Barnum was right..."there is a sucker born every minute" and "give "em what they want"....:lecture:
 
MudDawg said:
Sorry, but I found a complete lack of substantial hard data. A 25,000 rpm Brush commutated DC motor is not a modern marvel....I built slot car engines in the late 60's that turned more rpm, its a matter of commutator phasing, brush float and the ability to withstand the centrifugal and frictional forces...and my balancing station was a pair of razor blades...I really would like to see a parts diagram to know the mechanical configuration...the fan blade (from what can be seen in one picture) is not even a air foil design, and is straight edged...all bad news for a high rpm blade....i'll bet the thing goes into cavitation at the slightest resistance to air flow....and the design of the housing is very poor as design relates to fluid flow....thats it, i'm done with this one after my parting shot.....PT Barnum was right..."there is a sucker born every minute" and "give "em what they want"....:lecture:
Click to expand...

The pictures leave a lot to be desired for sure. I am not sure if the picture is showing the fan blades or an intake or exhaust straightener. Agreed 25,000 rpm is not new, my 35 year old dremel tool does 30,000 rpm, but it is not a typical axial fan speed, which was my original point. I am concerned about the housing as well, I suspect there is a ridgid housing inside the housing we are seeing that the fan is enclosed in, assuming these guys are for real. All the other so called, and even real electric supercharger sites and products I have seen appear to all have major design and operating flaws and issues.
 
You know with an unlimited 120 volt wall socket power source at hand all we really need is a huge 100 psi hydraulic pump plumbed straight into the intake manifold and we could make the engine generate 900 HP output with say a 1200 hp hydraulic pump feeding the intake :laugh: :rof::D

OK, that was fun!:sunshine:
 
MudDawg said:
....i'll bet the thing goes into cavitation at the slightest resistance to air flow....
Click to expand...

Air turbines don't cavitation. Propellers cavitate - something I happen to know a lot about and have lots of experience testing.
 
I can see the 5-15 seconds of intermittent boost being helpful for some racing applications where you're only hitting WOT on the straightaways. For passing power, maybe..
 
lawsoncl said:
I can see the 5-15 seconds of intermittent boost being helpful for some racing applications where you're only hitting WOT on the straightaways. For passing power, maybe..
Click to expand...

Agreed. One of the things I found really interesting on their site was the tech analysis and statement they made that a fan like theirs was not benefial at anything other than WOT, because of the throttle plate restriction. They said that at less than WOT, opening up the throttle plate a little more did the same thing as turning on the fan, except that the fan was less efficient than pressing the accelerator! That statement rang true as I was doing somne analysis of the physics involved, and I was having trouble with the throttle plate issue in my analysis until I read that statement which cleared it up for me.
 
This is so painful to read...

If electric fans hooked up to your intake actually provided some sort of performance enhancement, don't you think race cars would have them?

There is no way that some little fan is going to create enough boost to actually be worth even installing...

Hey here's an idea, why not just hook up an air compressor to your intake too! I bet that will work really well, until you back out of the driveway and realize it's plugged into the wall.

I really liked the comment about adding octane booster to go faster too... Because you know octane is like nitrous, it adds power, it doesn't protect against detonation or anything...
 
lawsoncl said:
Air turbines don't cavitation. Propellers cavitate - something I happen to know a lot about and have lots of experience testing.
Click to expand...

A fan and a propeller work on identical principals...the difference is the density of the fluid...air is much less dense than water...it is easier to cavitate air than water....I also am a professional that deals with fluid dynamics.
 
MudDawg said:
A fan and a propeller work on identical principals...the difference is the density of the fluid...air is much less dense than water...it is easier to cavitate air than water....I also am a professional that deals with fluid dynamics.
Click to expand...

Wow, that makes three of us!

I have considerable prior experience with ultrasonic cleaner systems that use cavitation for parts cleaning. Also experience with liquid pumps and pumps systems and their problems with cavitation. Also experience with indstrial fans and blower systems designs. I have heard of parasitic fan/blower speed - frequencies for impellers that must be avoided with variable speed drive systems! I have a text book and conference papers on it here somewhere, but I don't recall if they call it cavitation, or something else, vaguely thinking they called it cavitation, but it is operationally different that caviation in a liquid. It is more related to parasitic frequencies (blade rpm and blower dimensions) that have to do harmonics, tuning, resonate frequencies that need to be avoided in the design of the fan or blower.

Curious as to the details of what you have run into on the gas phase cavitation????? Also wondering if the defination of cavitation is different between the fluid phases. Liquid cavitation is caused by the mechanical collapse of gas bubbles in a liquid. How is it defined in a single phase gas?
 
MudDawg said:
A fan and a propeller work on identical principals...the difference is the density of the fluid...air is much less dense than water...it is easier to cavitate air than water....I also am a professional that deals with fluid dynamics.
Click to expand...
O.K. I don't have the experience that you guys have in this area but I have some questions. A propeller moving water cavitates because the reduced pressure of the water causes gas bubbles to expand and displace the water, right? So in an air moving fan, what does "cavitation" refer to? I know that if air flow to an air turbine (I am an A&P IA) is restricted, the air in the turbine drops to a lower pressure and flow stops. The air present in the turbine just starts doing very fast donuts in the housing. Ever wonder why the vaccum cleaner seems to speed up when you cover the intake? The motor actually does speed up because the density of the air in the turbine drops and places less load on the motor.
 
I'm used to defining cavitation as http://www.answers.com/topic/cavitation. I've never heard it applied to non-liquids.

For JeeperJohn - basically, the local pressure drops below the vapor pressure of the water and the water essentially boils and forms small bubbles. Particulates in the water or other dissolves gases affect cavitation as well. The collapse of the bubbles produces shock and sound wave that can damage props or significantly increase the detectability of a submarine. The size of the bubbles formed and the ambient pressure (eg depth) determine the frequencies of the sound produced. When the bubbles get large enough, but still way too small to see it sounds like sizzling bacon. Get real bad and the bubbles get visible and very audible.


Here's one of our larger test platforms. https://wrc.navair-rdte.navy.mil/warfighter_enc/SUBs/LSV-2.htm
 
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