The most expensive PC fan ever!

uhn113x · Post by **uhn113x** » 25 Aug 2005, 13:20

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by lighteninguk

i love the following quote....
<blockquote id="quote">quote:<hr height="1" noshade id="quote">cooled air burns more efficiently because their is more oxygen in the air<hr height="1" noshade id="quote"></blockquote id="quote">
wow.... never knew cold air had more oxygen in it....
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Doesn't it? Admittedly, the percentage in the mix stays the same, but cold air is denser and therefore has more mass for a given volume, hence using an intercooler.

uhn113x · Post by **uhn113x** » 25 Aug 2005, 13:27

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by bxbodger

And it only takes 12 watts!!!!
Woohoo!!!!-I think he's violated every known law of physics and invented perpetual motion into the bargain!!
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True - 15BHP = 746 x 15 = 11190 watts. I wonder how the 900 amps will come from the battery and alternator? Assuming the doobery is 100% efficient?
It will slow the engine down a bit, won't it? [;)] Probably lose more than 15BHP, as well. [;)]
Ho hum.......

dnsey · Post by **dnsey** » 25 Aug 2005, 14:53

A few years ago, just for fun, I tried running the 'blow' side of a vacuum cleaner into the air intake. Despite producing rather more airflow than a computer fan, the vacuum cleaner ended up being driven by the induction depression, rather than the other way round!

madasafish · Post by **madasafish** » 25 Aug 2005, 17:34

Trading Standards would love his website...
Makes Ecotech look believable..
Wonder if both together would give me better fuel consiumption and more power?
As cooler air gives more power, lets add a refrigeration unit.. as well..

citroenzx · Post by **citroenzx** » 25 Aug 2005, 18:02

now there's a good idea, refrigerate your whole engine bay and sent the generated heat into the car. also it provides a handy place to keep your drinks cool when out and about in the sun.

FrenchLeave · Post by **FrenchLeave** » 25 Aug 2005, 20:02

Quote, originally posted by uhn113x "True - 15BHP = 746 x 15 = 11190 watts. I wonder how the 900 amps will come from the battery and alternator? Assuming the doobery is 100% efficient?
It will slow the engine down a bit, won't it? Probably lose more than 15BHP, as well.
Ho hum......."
Er, doesn't the missing power come from the extra fuel burnt with the extra air?

bxbodger · Post by **bxbodger** » 25 Aug 2005, 20:39

To get perpetual motion you need to put less power into a system than you get out, and thats basically what they are claiming here, although I don't think they realise it!!!
Saying you can get an extra 15bhp out from only putting an extra 11 watts in is to claim you've invented a perpetual motion machine, no matter what way you look at it.

FrenchLeave · Post by **FrenchLeave** » 26 Aug 2005, 00:49

Sorry mate, in that case no turbocharger or mechanical supercharger would work. You are taking a finite amount of power out of the exhaust system (or from the crankshaft) to drive the turbocharger/supercharger (equivalent to taking x watts from the battery to drive a fan) but will produce much more power as a result. The difference in the energy equation is, as I previously wrote, made up by the release of energy from the extra fuel burnt. There is nothing there that contravenes either the first or second laws of thermodynamics.
That is not to say that this daft idea would work, but it's not about contravening the laws of physics or producing perpetual motion, more a question of scale.
Think about it; provided the compressor is the same size and is driven at the same speed, it doesn't matter what driving mechanism you use, be it mechanical, electrical or turbine. The output airflow and pressure would be identical and so would be the engine output.
Aren't these arguments good fun?

bxbodger · Post by **bxbodger** » 26 Aug 2005, 01:49

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Aren't these arguments good fun?
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They certainly are- its like a virtual pub!!! I was referring to the outrageous claim of 12 watts in, 15 bhp out-if it was at all possible you could run a 2cv size car on a pp3 battery!
They still haven't replied to my email........

FrenchLeave · Post by **FrenchLeave** » 26 Aug 2005, 03:11

OK everybody, I've just seen the obvious weakness of my argument. A 12 watt fan cannot possibly supply enough air to successfully combust sufficient fuel to produce 15bhp. But like I said, it's just a question of scale; you always get more power out of a turbo or supercharged engine than you put into the charging system, the difference is from the rate of combustion of the extra fuel burnt.
I seem to recall that in the thirties there was a supercharged Mercedes Benz (SSK something or other I think), where the blower was driven from the crankshaft via a clutch that was only engaged when the throttle pedal was fully depressed. Must have been rather like an electrically driven blower with its on/off action?

Sl4yer · Post by **Sl4yer** » 26 Aug 2005, 03:58

Its late, and I've had a few beers, but I'll try to make sense of this.
As I understand it, a turbocharger or supercharger is boosted by its own success, i.e. it produces more power (a small amount, probably initially at the expense of engine output in the Merc clutched supercharger) which drives it faster, which in turn produces more power, etc. etc.
Think of the arguments about how increasing the max boost on an XUD turbodiesel won't give more power without increasing the fuelling. The increase in fuelling enables the increase in boost. An electrically driven 12 watt PC fan won't respond in quite the same way! As dnsey found with the vacuum cleaner, the intake of air would surely drive the fan, not the other way around!
If it were that easy, would cars travel faster into a headwind?! [:0]

bxbodger · Post by **bxbodger** » 26 Aug 2005, 04:44

I've got a reply from the seller!!!!!![:D][:D]
I asked him if I'd need two for my Vitesse as its twin carb-would I get double the power? Here's the answer, pasted verbatim-
<blockquote id="quote">quote:<hr height="1" noshade id="quote">To start with the increase is between 8-15hp. The electic fan in the Power Booster creates an extra 5000 litres of air per minute, providing the engine with constant ram air. As these are fitted before the air filter there is no need to fit two, if more power is required the best option is to fit a Power Transforming Unit (PTU). For more information on the Power Booster and the PTU please visit our website at www.powerandeconomy.co.uk
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So I would need a 'power transforming unit' then...........I may email him back and ask him why if its fitted before the air filter, as he says, the one on the Glof on their website is fitted after the air filter!!!!!!?????http://www.powerandeconomy.co.uk/power_booster.html, unless I'm very much mistaken.....
And god alone knows how it would be fitted before my K&N's.....[}:)]

FrenchLeave · Post by **FrenchLeave** » 26 Aug 2005, 05:13

So how much air would you need to produce 15bhp? Please bear with me whilst I do a simple sum (if you see any errors I'm sure you'll tell me!).
The CHRIS manual for 1991 (look it up on Google) gives the calorific value of gasoline as 43.2MJ/kg.
15hp is 15 x 746 watts = 11.19kJ/s
So at 100% efficiency, to produce 15hp requires 11,190/43,200,000kg/s
= 0.259 grammes of fuel per second
Assuming 25% efficiency, you would require approx 1 gramme of fuel per second.
So for stoichiometric combustion you'd require approx 14 grammes of air per second.
Density of air at NTP = 1.293kg/m^3 = 1293g/m^3
So volume of air required = 14/1293m^3/s = 0.0108m^3/s = 10.8 litres per second. A little over 2 gallons of air every second.
Question - is an 11 watt fan capable of supplying 2 gallons of air every second?

uhn113x · Post by **uhn113x** » 26 Aug 2005, 13:27

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by FrenchLeave

Quote, originally posted by uhn113x "True - 15BHP = 746 x 15 = 11190 watts. I wonder how the 900 amps will come from the battery and alternator? Assuming the doobery is 100% efficient?
It will slow the engine down a bit, won't it? Probably lose more than 15BHP, as well.
Ho hum......."
Er, doesn't the missing power come from the extra fuel burnt with the extra air?
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My theory is that is smoke, mirrors, and someone's bank balance [}:)][;)][:D]

bxbodger · Post by **bxbodger** » 27 Aug 2005, 04:40

I've had another reply from him!!!!
I asked him why the one on the website picture wasn't fitted like he said it should be- here's his answer, again pasted verbatim-
<blockquote id="quote">quote:<hr height="1" noshade id="quote">Full marks for being so observant! The picture of the Power Booster in question was taken by the company that designed our website, and they fitted the Power Booster without reading the instructions correctly, and we have yet to rectify this mistake. Please be assured however, that where ever possible it is fitted before the air filter.

Jon.
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So, it was the website designer who did it wrong!!!!!You'd have thought that Mr Ridgeway would have checked it first, even had one on his own car to photograph.......but no.......