Model Boat Mayhem
The Shipyard ( Dry Dock ): Builds & Questions => Steam => Topic started by: nhp651 on April 26, 2011, 10:50:26 am
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I put my question to those with knowledge of BOTH steam and electrics.
1) How much juice does a converter/inverter take ( such as on a narrow boat, but without alternater to keep the battery charged) out of a twelve volt battery to run an applience of 240 volts?
2) the second question is: would a steam cleaner or steam stripper produce enough steam and run a low pressure twin cylinder steam engine such as a Stuart Twin ( not the model double ten but for one used for small steam launches)? say on a small 12 foot launch throwing an 8 - 10 inch prop.
3) if a system like this produced enough steam to run such an engine on low volts/amps usage instead of using a conventional copper boiler, would it ever need a steam certificate for safety?
An interesting concept, and I have an idea, lol
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With respect to question 2 the kW rating of the steam generator will give you a clue to the amount of power available before all the efficiency losses are allowed for. I've no info on full size launches but I would think it would need several kW to power it effectively. Much easier to push the electricity into an electric motor - but less fun.
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Question 1 I can answer but the other 2 {:-{
what ever the wattage of the appliance is, divide by the battery voltage and add about 10-15 percent for Inverter Inefficiencies, say you are running a 2400 watt toaster and your battery bank is 12 volts, then the current draw isaround 230 amps.
Nick
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Ummmmmmhhh............back to the drawing board then, {-) %% %% {:-{ {:-{ {:-{ {:-{
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You could build a flash steam hydroplane and feed 240 volts down the tethering wire!
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A steam stripper would not run a steam engine at all well, if at all, due to the condition of the steam, ie. very very wet. It also would not have the pressure to compensate for the saturation levels- basically your engine would do about 50rpm, intermittantly at that, and fill up with water.
Not sure on the boiler cert'- it depends on the Bar(pressure) x Litre(volume) measurement- anything over three BarLitres requires an inspection and a certificate.
The real question is- why would you use electricity - to power an electric element - to boil water - to power a steam engine - to produce electricity??? O0 {-)
Greg
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just for the theorist, greg.......was having a senior thinking moment as my sixtieth approaches, lol
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A steam stripper has almost negligable pressure so not much use. But wait, early engines worked at about 4psi, and Newcomen engines at equal or sub atmospheric. So what you need is an engine with a good condenser which will give you nearly 15 psi differential which is about what Mamod engines work at so perfectly do-able. Also the Davy Safety Engine worked at below atmospheric pressure.
Your big problem for the launch is when you string all those extension leads together to get mains electricity to your stripper will vaseline be enough to keep the plugs from shorting.