A Different Application For A Torque Converter

[WhackyWheels]

Could anyone explain (to some degree of detail) why an automatic transmission torque converter could not be used in some capacity as a dynamometer brake.

With the internal stator, impeller and turbine it looks like a possiblity.

If there is a question as to why not simply buy a purpose built unit? The answer, I have all sorts of materials, parts and pieces with the addition of loads of time to do so.

Thanks for anyone's help.

 

[patprimmer]

How would you control the applied load to the desired level.

I imagine you will have trouble controlling the heat in the fluid, and any variation in heat will vary the load, so it might be difficult to hold a constant load for long enough.

Also water for a waterbrake is VERY CHEAP vs ATF.



Regards
pat pprimmer@acay.com.au
eng-tips, by professional engineers for professional engineers
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[WhackyWheels]

PatPrimmer,
Instead of oil I would use water. Cooling the water would be done close to the same as oil. The differences are fluid temp fluctuation and viscosity.
Controlling a load against the torque of the engine will be done by providing a fluid port entrance at a strategic spot, and a fluid port exit at a location determined by the internal design of the unit, and the variation of it's flow-rate. Because of the dynamics of the test procedure, the flow will be done with a closed-loop servo system.

Thank you for interest.
However, I'm not sure if it could be done.

Anyone else's help would be a great help.

Thanks again

 

[strokersix]

If you proceed with this project and use water you might consider water based machining fluid as I think it may provide some lubricity for the moving components inside the torque convertor while simultaneously having higher heat capacity and lower cost.

 

[WhackyWheels]

PatPrimmer and Strokersix,

Thanks for your help. I really appreciate it


WhackyWheels

 

[SMOKEY44211]

Using an automatic trans converter is very doable. Biggest problem I encountered was airation of fluid. Somewhat rpm limited as converters tend to "ballon" at elevated cycle speeds. Cooling is easy. Airation effects can be delayed by using a large quantity resevoir. Not the best method for analytical data but for comparision purposes its very cost affective.--------Phil

 

[shanba]

The stator is there only to increase torque output of the converter. For a dyno, you may not want to use this. It would become a simple fluid coupling. Strain gauge on the turbine shaft would give you nice torque information.

 

[philipmtc]

A German company, Voith, do pretty much what you are asking about. They make driveline retarders for trucks. The retarder torque is controlled by the flow of fluid into and out of the turbine via proportional valving. Cooling is by a heat exchanger coupled to the truck cooling system.

 

[bub579]

Your idea brings back a lot of memories. Back in the 70's I was involved in the installation and operation of a water-based chassis dyno. Some info you might find interesting: With supply water at 60F; the piping must be sized to flow 13 GPM of city water to cool 200 horsepower. The average test consumes approximately six gallons of water. The above info provided by Clayton Industries, El Monte, CA. bub