| Impulse Turbines |
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| The picture at left shows an attempt to make an impulse turbine (a Pelton wheel) out of sheet metal. The gap between the buckets meant that it never functioned as intended, however it worked quite well as a Turgo turbine after I took one side's buckets off. |
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| The buckets were from a sheet of soft aluminium. Originally they were circular, with a tab attached for mounting. I formed them into buckets by a combination of drawing and wall ironing. |
| The tools used were a punch with a hemispherical end and a toroidal ring with a smoothed-edge centre hole, like a donut. The turbine shown above would not work for long as part of an engine, but I could see it as part of a basic hydro scheme. On a similar theme, I made this: |
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| The chief attraction of this device is that the 'buckets', the U-tube segments, can be easily made with basic tools. All that is needed is a benchtop tube bender and hand tools. There are a couple of potential advantages over the usual bucket-equipped impulse turbines: the tubes enclose the flow, letting this work well with high-speed gas, and the tubes may also be welded to each other so that the rim of the device is an unbroken hoop. Unfortunately there was a great deal of fabrication work involved - this took two months of spare time, far too much for a commercial proposition. |
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| It did spin up very impressively on compressed air, though. I tried seeking funding to get this turbine's efficiency checked, but that was just a basic lesson in how and why the system hates unknown inventors. So here it is: it may help someone with little money but lots of cheap labour. |