I recently required a smoke generator (ultrasonic Type) it is not in working order but I have rigged it up to test and bypassed the circuit board powered by 2 X 12 volt batteries and managed to get the vapourising unit to function, and the 12 volt fan motor with a separate supply to also work. With some work to replace the 12v to 24v converter CN6009 it should satisfactory. This unit appears to be a DIY job but very similar to MMB Foggy Smoke Generator which is available. Note the component required CN6009 I have sourced on ebay. Soon as it arrives I will set it up and test its suitability for a 1/24 scale TID tug boat model I am building. Problem might be size of smoke generator and other components required to fit in the hull in addition to a 12 volt 9ah battery scooter battery, there aint much space.
There are smaller smoke generators available which burn oil (fan powered) which I have in one of my other models (Blazer Tug Boat) which is OK with no wind and close up but at any distance hard to detect if any smoke is being produced. The Oil recommend for this unit is Baby Oil which smells OK but I have wondered if I could use another oil based fluid which would produce more smoke (Any suggestions)?