T-Pain Is On A Boat: Re: [Electric Boats] Dirty prop

Monday, June 3, 2013

Re: [Electric Boats] Dirty prop

That happens to my prop

Being a small fantail launch thats still diesel :(

I can see the wake from the prop easily

When the props dirty the engine revs much higher and there is a tube of aerated water behind the boat at the height of the prop

As the barnacles spin off the revs drop

The engine works harder and boat speed increases

The tube of aerated water also starts to disappear

Nick

On 03/06/2013, at 11:37 AM, Dennis Wolfe <wolfeboats@gmail.com> wrote:

The critters must be affecting the blade profile and reducing its "bite" on the water. More turbulence, less thrust, less power needed to reach whatever rpm corresponds to 48v.

On 6/2/2013 9:07 PM, R&M Mair wrote:

My prop is currently got some critters attached. I notice that instead of 20 amps giving me 3.6 knots I now need 25 amps to get 3 knots. This makes sence to me. The thing I do not understand is why full throttle now tops out at 45 amps. I get a about 4.8 knots at 65 amps with a clean prop. Should I not be able to hit max draw of 100 amps with the prop like this or at least get the 65 I got before. All at 48 volts. Electric Yacht 100ibl system.
Richard