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Re: airplane powered car, with the correct engine this time.

I would also think that the application of hours at a constant speed as opposed to the instant acceration of it in a dragster would help it last longer also.  But that is just me thinking not any inherent knowledge.

Racing 4 Nickels - 1989 Oldsmobile Cutlass Ciera
2011 SHOWROOM-SCHLOCK SHOOTOUT  IOE Winner
2012 The Chubba Cheddar Enduro Class C winner
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127

Re: airplane powered car, with the correct engine this time.

yeah, i get the exact same feeling, but we're asking for 10hours of continuous operating time instead of 32 seconds in 8 second bursts. that's a very different operating environment.

i suspect nobody really has the answer for me, but it's worth asking.

Re: airplane powered car, with the correct engine this time.

People also use those big gilmer belts for PSRU on auto-engine experimental aircraft.  Gates wants NOTHING to do with that, to such a degree that they put ads in the airplane mags years ago pleading with people not to use non flight certified belts for aviating.

So don't talk to Gates about connecting a belt to an aircraft engine, or they will hang up the phone and have you arrested.

Google up "Belt drive PSRU" and see if the HP ratings are available.

Jim C.
If God meant for us to race, we'd all have baggy Nomex skin.
08TMS.09NL.10GM, SP. NL.11SP, NL.12SP, VIR, NL.13GM, NJ.14NJ, VIR, WGI.15AB,16GM...

Re: airplane powered car, with the correct engine this time.

Back when I was racing boats a friend of mine built a Unlimited hydroplane powered by eight Mercury V6 (~300HP ea.) powerheads.
They were arranged in four pairs with a single prop shaft running down between them.
He used Gilmer belts from the motors to turn the shaft.
...it's not ten hours, but it is a lot longer than eight seconds.


http://www.youtube.com/watch?v=zcOPV_Lp_TM

Re: airplane powered car, with the correct engine this time.

May or may not be of interest to you, but the Robinson helicopters use a simple belt drive. The larger one, the R44, has an IO-540, probably 250HP or so. Not a life-limited component, AFAIK, so probably designed to last at least a few thousand hours. I think they actually use four matched v-belts instead of the single, toothed belt on top fuel and funny cars.

Team Fairlylame
HumidiTT '14 IOE Winner

131

Re: airplane powered car, with the correct engine this time.

the problem with PSRU belts is that everyone that sells systems like that is selling $400 worth of parts for $10,000 and does not give out any information about their parts.

also, their belt lengths are usually relatively short. but if they use a comercial off the shelf belt that can be purchased in a different length it could be perfect. 300hp is in the range for these units.

this site has a bit of info: http://www.epi-eng.com/propeller_reduct … erview.htm
this one is of note:

With belt-PSRU’s, typically, the life of the belt is limited to two or three hundred hours at the loads imposed by a piston engine, which can affect reliability considerations;

a couple hundred hours sounds great, i'd be happy if a belt lasted an entire weekend (with a good safety margin of course)

I've already come up with a design that puts a brake on the turbine output when the belt loses tension to prevent overspeed, but i'd rather that system go completely unused.

132 (edited by erich 2013-12-06 12:41 PM)

Re: airplane powered car, with the correct engine this time.

Have you looked at the Gates GT2 design manual?
A 20mm pitch GT2 belt can move over 300hp if the load is in the right RPM range.

http://www.gates.com/catalogs/file_disp … s\catalogs

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Re: airplane powered car, with the correct engine this time.

once you add the application service factors in and you account for the 6000RPM rev-limit it falls quite outside of the range of the selection guides.

even if you don't account for the service factor, the only belt that can handle 300hp is only designed for 2000RPM.  and if you use the belt rated for 250hp or so, you have a max RPM of only 3000RPM.

from what i understand, the limit on these belts isn't the max torque, they are strong enough. but rather the heat buildup that destroys them. that's why the RCD ones replace the steel belting with carbon fiber strands. the carbon fiber generates less heat in flexing.

Re: airplane powered car, with the correct engine this time.

Harley Davidson powered bikes use both primary and secondary belt drives. 

300 HP is a bit more than all but the blower motor bikes put out but the 3" belts usually fail due to picking up rocks not wearing out.

From page 175 in that above referenced Gates guide:

7. High Performance Vehicle Applications
For special high performance applications, such as motorcycles or race car and boat supercharger drives, the design loads will typically exceed published data. Because of the extremely high loads and speeds (as much as 500 HP and belt speeds exceeding 10,000 fpm), it is necessary for the
designer to contact Gates Power Transmission Product Application for additional assistance.
Although special considerations may be involved, it is important to remember that reasonable drive recommendations can be provided to the designer in most cases

El Capitan de los Bastardos De LeMons
1993 Linco Mark Ate
1957 Renault Dauphine
Driver with LemonSpeed's V6 Mustang

Re: airplane powered car, with the correct engine this time.

Wetbed0 wrote:
Marc wrote:
Wetbed0 wrote:

Use mufflers, less restriction than filters, and designed to reduce noise.

is there anything off the shelf available for this kind of volume? (1100mph on a 7" diameter intake) ?

1100 mph*5280 feet per mile*(pi*.291(ft)r^2) area /60 min per hour = 25,752 cfm. So dived that by the expansion rate of combustion of roughly 4.2, and you get 6131 cfm. So you need an exhaust for a car that has an intake of 6131 cfm. Probably similar to a large diesel. I can only guaranty the first number is remotely accurate, the second came from the internet.

The mass flow ratings on the engine top out around 4 LB/S airflow.  240 LB/Min.  Air weighs ~0.08 LB/FT^3 at STP.  I get 3000 CFM from that.   More reasonable than 6,000 CFM.  The exhaust will have much of the energy removed by the free turbine so the flow will not be 4.2x intake and as Marc commented elsewhere, the intake is the loud part.

3 stacked 14" race type air filters will flow 3000 CFM http://www.wixfilters.com/Speciality/Racing.aspx

Same turbine on a bike: http://www.southbayriders.com/forums/threads/127380/

El Capitan de los Bastardos De LeMons
1993 Linco Mark Ate
1957 Renault Dauphine
Driver with LemonSpeed's V6 Mustang

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Re: airplane powered car, with the correct engine this time.

Off by a factor of two on an estimate like that isn't that bad smile

but i think you're onto something, i can just make something to stack filters till the engine achieves full power(or close to it). i can test it on the dyno to confirm the appropriate number of filters to use.

Re: airplane powered car, with the correct engine this time.

I feel pretty good about that having not taken thermo or fluid dynamics at the time. Still a really cool project that's a lot of fun to follow.

Re: airplane powered car, with the correct engine this time.

I love it...

A million bucks in engineering, ...

To get a 500 dollar car together.

A quote from TheEngineer "you have a lot of confidence for someone looking to play with chrysler parts."
A professionals quote "so what if that comma in the price tag of your rig is in the same spot the period is on mine, I STILL beat you smile"

Re: airplane powered car, with the correct engine this time.

Digging up this old thread cause I'm new and it's cool. Any progress?  I got to watch some of the Arlen Ness jet bike build in my stepdad's shop back in the day. Back then I thought that a turbine engine with a hydraulic drive would be a good setup. Keep the turbine spinning at a happy consistent rpm and control vehicle speed via the hydraulic control valve. I figured, in the bike configuration, that the valve could be actuated by the twist grip: instantaneous application of torque. Any thoughts from actual smart people?

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Re: airplane powered car, with the correct engine this time.

Bandit13 wrote:

Digging up this old thread cause I'm new and it's cool. Any progress?  I got to watch some of the Arlen Ness jet bike build in my stepdad's shop back in the day. Back then I thought that a turbine engine with a hydraulic drive would be a good setup. Keep the turbine spinning at a happy consistent rpm and control vehicle speed via the hydraulic control valve. I figured, in the bike configuration, that the valve could be actuated by the twist grip: instantaneous application of torque. Any thoughts from actual smart people?

No, the progress on this is more or less stalled. My situation has changed and i just don't have the time and mostly money to dedicate to this at this point in time. This project will proceed at some point, but not any time soon.

as for hydraulic motors and valves, it's mostly unnecessary because the design of a free power turbine jet essentially already includes a massive torque converter:
https://upload.wikimedia.org/wikipedia/commons/8/84/Turboshaft_operation.png

note how the power shaft is not connected to the gas generator (compressor & compressor turbine)?