|Setting up through hull cooling|
conventional method of cooling an engine in a marine
environment is to have a seacock where salt water can be
drawn in and used to cool an internal water circuit
connected to the engine. These units require diligent
maintenance, especially with sacraficial anodes, or they
will corrode very quickly.
There is another alternative with steel boats that makes more sense to us, through hull, or skin cooling.
|There isn't a
whole lot of information or research available on this
subject, just examples of other peoples experiences.
There are two methods of closed loop skin cooling:
1-A split pipe along the outside of
the hull, around the keel
calculations could vary widely depending on the
dimensions of the box, square, rectangle, number of
We have decided to go with the box type as this won't effect the outer hull. Origionally it was going to be a square, about 15 square feet, on each side. But because of conflicting data we have found, ( ie 1/2 square foot per horsepower to half that again, to almost twice that! ) we are making it length-wise. 16 feet long x 1 foot on each side.
|For this we
have had some 1/8" plate cut into 11" to
13" strips, and bent to a 45º on the sides. Of
course this couldn't be used whole ( it would've been
nice! ) as it needs to curve around the hull between
stringers. ( Photo at the top )
We are going to place baffles every foot or so to keep the water stirred up. This is very important because the flow isn't very fast and without baffles, the hot water would just remain at the highest point, away from the hull where the cooler water is!
I cut out 1 1/2" high slots through 8 frames and then slightly bent each piece so it would slide in easier ( by jumping on it haha !) then marked and cut the ends to get a "curve" in the overall shape.
The reason we went with 45º
on the edges was so Gena could easily get good welds to
the hull along side the stringers.
7 hours - Cut and fit thru-hull cooling plate, cut 16 slots into frames.