Guru
Joined: 15/07/2006
Location: AustraliaPosts: 497
| Posted: 02:50am 12 Nov 2021 |
It is around a year and a half since testing.
Kerme has been cut up.
And re-modeled. I won't go into all the details of the fibreglass work, but we have cut a lot of weight out, and used much lighter foam for buoyancy. The floor is above waterline and no space for water to catch in the boat. No need for pump. Any water runs out for itself. Basically it is a floating cork. Around 70kg for the hull.
The battery pack is 48v 100Ah. Around 50kg.
The first test is with the pod motor L10, 22kg. And 2 people, add another 120kg. Total weight on test around 262kg.
Here is Kerme with the L10 pod motor in action.
The data numbers
km/hr Amps
4 3
5 8
6 11
7 15
8 23
9 32
10 40
11 53
12 66
13 68
14 77
15 90
16 104
17 107
18 108
Also measured distance traveled during testing, 2.02km and used 24Ah. Of course this is not all that relevant as the speeds were all varied.
Then was the test on the 20hp motor, 40kg. Total including 2 people 280kg.
There is a few gaps in the data numbers. The water was very rough with strong wind that day. We did the testing cross wind to avoid the wind hindering or helping. The choppy water didn't help either. Don't know why but could only get 158A on that day.
km/hr Amps
5 6
6 13
7 23
8 35
9 37
10
11 66
12 73
13
14 76
15
16
17 100
18
19
20
21
22
23
24 158
In comparison
1) Original shape. 114kg plus .. Total 346kg. No performance numbers. This is like a bath tub. But still can't sink. Floor is above waterline with self drain holes.
2) With the second pontoon width added, 130kg plus .. Total 362 or 372kg depending which motor. Max speed 24km/hr with 191A. With motor height adjusted a little, got 25 km/hr 189A.
3) With v-bottom tunnel and single width pontoon. Probably still 130kg plus .. Total 362kg or 372kg But I don't think I tested the heavier motor on this configuration. Achieved 24km/hr at 175A.
4) No comparison drawn with the twin motors.
5) New Kerme shape and weight has resulted in some better efficiency, 24km/hr with 158A. Top speed should be higher but don't know why it didn't give more amps.
Edited 2021-11-12 12:52 by Trev