Boom Tent - Air Movement

[otherthan]

this summer on a hot day working in my boat was very hot...so I instaled a boom tent...as soon as it was up you cauld feel air mouvement thrue the cabine...so I figured why not instal a tent over the front hatch?

funny thing when I did the nice gentle breeze stopped...my girlfriend accidently triped on the bungies holding the front tent and it slipped off the hatch...the airflow imidiatly started again.

is it possible that when the sun heats the bow...heats build up in the V-berth and raises out the hatch fast enough to creat airflo inn from the companionway across the cabine...and sins the air under the boom tent is shaded and cooler a breeze is created??

anyone noticed this or its my imagination

[Hudson Force]

I wouldn't totally discount the convection current that you describe, but I don't think that is what is happening. The easy test to determine if the breeze is produced by convection would be to note the presence of the air flow when there is zero movement of air from any existing light wind. I think that it is more likely that the two tarps are both capable of funneling and concentrating some existing breeze, but they are working in opposition to each other. Cowl vents over dorade boxes will do this unless they are facing in opposite directions. I suggest you tweak your breeze potential by reversing the end of the forward tarp that is higher. Likely best when the aft of the aft tarp is higher and the fore of the forward tarp is higher.

[capngeo]

I have tents fore and aft....no problem with airflow.... BUT when at the slip, the stern faces East which is where the trades blow in Key West most of the year. The forward tent is mesh (shade cloth) as is the sides of the aft one. When on the hook, I use a scoop in the forward hatch instead of the shade


IMG_0762 by capngeotoms, on Flickr


(Stock Pic)

[imagine2frolic]

I used a scoop also, and at the dock I would face it in different direction to keep air flowing........i2f

[otherthan]

scoop looks like a must have...

I wasent shure about my experience this sumer...cauld of been wind coincidence? so I will not go ahead and paint my bow black

by the way love your tent...much better then my canadian tire tarps

[imagine2frolic]

I got rid of the wooden sticks in the scoop, I think there were tie downs already on the corner, but maybe not. I may have added some small line? I did add small pad eyes in the corner of the hatch. This allowed me to turn the scoop in all four directions. I have seen scoops that were square with the center divided in half twice. I don't think these would push as much air as the spinnaker type shown through the boat........i2f