How can I calculate the size of paddle wheel?

I need to build a boat with 2 6V motors with 185rpm and 1.5 [kg * cm] torque.
the total Weight of the boat is 3kg.
got double hull boat length of 60cm and width of 7cm each
probably I will use paddle-wheel because low rpm.
How can I calculate the size of the paddle wheel?
i look at the books and i can not understand how to calculate and design the paddle-wheel.
please help.

 

Here is an idea. if you know your shaft torque, find the power available at paddle max distance . Then isolate the area in displacement formula . its no where near a perfect example but should do just fine for what you need

I can find the equations you need once i get home. Let me know if it still bothers your.
rewrite Vdispl as a area time length .

 

i would thank you if you share the right equations..there are too much information in the books so i don't know what to use.
thank you a lot!

 

Dont take it as a awnser this is my aproach to your problem with some predefined variables such as diameter and arc lenght.

it might not be truth, but all the equations you need to solve the problem should be there.

i did a quick google search and were able to find quite alot information to your problem.

My aproach is just a educated guess from my background as a marine engineer and i choose to handle this problem by simplying it, rather too much =). efficiency is not taken into account and instead of (g) you are probably gonna use water friction. Since my calculation concern of moving water up! witch is not your case.

Paddle wheel calculations, please ? http://www.scienceforums.net/topic/65768-paddle-wheel-calculations-please/
Paddlewheel Most Efficient Operating Speed - The Giraffe Boards https://www.giraffeboards.com/showthread.php?t=35679

Paddle wheel torque calculations - Fluid Power engineering - Eng-Tips http://www.eng-tips.com/viewthread.cfm?qid=252396

 

Thank you so much.. It will do the job.

 

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