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Step 4Float Your Boat.
To see the fire boats working to their full potential, they need calm. Calm air and calm water.
We poured shallow pools of water into plastic trays and left them to settle. We also closed all the windows and doors to prevent draughts, and walked slowly so that the breeze of our passing wouldn't disturb the boats.
Place the boat at one end of the tray and light the candle.
As the candle burns, it heats the air around it. As you are probably aware, warm air rises. This is a convection current.
When the rising air hits the sail, it is deflected from its vertical path, which exerts a small, but real, force on the sail. Since the sail is fixed to the boat, the boat moves.
This video shows a couple of the boats my clubbers made:
We poured shallow pools of water into plastic trays and left them to settle. We also closed all the windows and doors to prevent draughts, and walked slowly so that the breeze of our passing wouldn't disturb the boats.
Place the boat at one end of the tray and light the candle.
As the candle burns, it heats the air around it. As you are probably aware, warm air rises. This is a convection current.
When the rising air hits the sail, it is deflected from its vertical path, which exerts a small, but real, force on the sail. Since the sail is fixed to the boat, the boat moves.
This video shows a couple of the boats my clubbers made:
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Science+imagination=Instructables.
Firstly, Newtonian mechanics (physics) coupled with fluid buoyancy effects (Archimedes) is causing the propultion. Convective heat transfer only causes fluid buoyancy (of the air) which has an action/reaction with the sail.
Secondly, could you consider rather funnelling the hot air into a converging tube that draws air under the boat allows the hot air to push against the water? This should provide a serious increase in propulsion! I have seen such a tube made from a hollow kettle element, but a crimped copper tube should suffice. Any thoughts on such improvements?