Sunday, December 29, 2013

9x6 Propellor, 3Cell, Benchmark

Finaly my 9x6 props arrived. It's a HobbyKing APC Style 9x6 propellor. This is not a genuine APC prop. It is a cheap hobbyking clone. And to be honest the quality is cheap. The quality of these props is even a lot worse than the hobbyking slow fly props. The prop tips break very easy and all edges are very rough.  I bought these because this where the only affordable 9x6 props that come in CW and CCW configuration.








The difference between puller and pusher configuration is ~8% for this setup.
The values in bold at 225 gram thrust is what I need for my current Y6-copter project.
Test is performed with a 12V power supply (= 3Cell lipo battery).



Thrust
grams
9x6 pull
Watt
9x6 push
Watt
push-pull
%
25 4,0 3,2 21,1
50 6,5 5,8 11,3
75 9,8 8,8 10,8
100 13,2 11,5 12,8
125 16,2 14,7 9,7
150 20,3 17,8 12,0
175 22,4 20,8 7,1
200 25,0 25,0 0,0
225 28,8 28,8 0,0
250 32,7 32,5 0,6
275 37,3 36,4 2,5
300 45,9 40,9 10,8
325 51,9 44,9 13,4
350 55,8 50,7 9,1
375 59,4 54,9 7,6
400 65,4 59,2 9,5




Friday, November 8, 2013

Coaxial 10x45 + 11x47 Propellor, 3Cell, Benchmark

In this benchmark I have tested a 1045+1147 setup and a 1147+1045. The conclusion is that mounting the largest prop on the top motor causes the most efficiency loss. So it is better to keep the smallest prop on top and the largest prop on the bottom motor. But in my case this is less efficient then mount the same props with same size and same pitch.

thrust

(grams)
10x45+11x47 benchmark
(watt)
10x45+11x47  theoretical
(watt)
11x47+10x45  benchmark
(watt)
11x47+10x45  theoretical
(watt)
50 5,4 5,6 6,4 5,3
100 11,1 10,5 12,6 9,7
150 18 16,2 19,5 15,1
200 25 21,7 27 20,6
250 33,1 27,6 35,2 26,8
300 41,8 34 44 32,9
350 51,7 40,4 52,2 39,3
400 59,8 47,8 62 46,3
450 68,7 54,4 72,3 53,9
500 77,2 62,7 83 62,2
550 86,1 71,3 95 70,2
600 97,6 79,8 106 79,3
650 109 89,9 116 87,5
700 119,3 100 125,9 96,2
750 130,8 106,7 135,9 103,3
800 142 117,3 147 113,7

(lower is better)

Thursday, November 7, 2013

Coaxial 10x45 + 10x60 Propellor, 3Cell, Benchmark

Another combination. This time two 10 inch props with different pitch. Mounting the prop with the highest pitch as bottom prop has again a positive influence on the efficiency loss.

thrust

(grams)
10x45+10x60 benchmark
(watt)
10x45+10x60  theoretical
(watt)
10x45 Coaxial benchmark
(watt)
10x60 Coaxial benchmark
(watt)
10x45+10x60
Theo-Bench
(%)
50 7 6,4 6,5 6,6 8,6
100 12,6 12 12,5 12,7 4,8
150 18,9 17,5 18,9 19 7,4
200 25,4 23,9 26,3 26,5 5,9
250 32,3 29,8 34,3 33,2 7,7
300 40 36 42,8 41,4 10,0
350 48,3 42,2 51,1 49,9 12,6
400 55,7 50 58,5 56,8 10,2
450 64,2 57 68,5 65,6 11,2
500 74,6 65,2 77,5 72,7 12,6
550 83,9 73,6 88,6 81,7 12,3
600 94,7 82,3 99,3 91,4 13,1
650 103,6 91,2 112,6 100 12,0
700 112,8 100,3 122,3 109 11,1
750 123 107,7 135 118 12,4
800 134,5 117,7 145,8 125 12,5



(lower is better)

Saturday, November 2, 2013

Coaxial 9x47 + 11x47 Propellor, 3Cell, Benchmark

The 11x47 prop performed well in the single prop benchmarks but in coaxial configuration a huge efficiency loss was set. In the 9x47 + 11x47 mixed coax combination there is no suprise. This setup, as aspected, does not perform as well as the standard 9x47 coaxial setup.

thrust

(grams)
9x47 + 11x47 benchmark
(watt)
9x47 + 11x47  theoretical
(watt)
9x47 Coaxial benchmark
(watt)
11x47 Coaxial benchmark
(watt)
9x47 + 11x47
Theo-Bench
(%)
50 6,4 5,7 6,2 5,4 10,9
100 11,6 10,3 9,9 10,5 11,2
150 17,9 15,4 15,6 16,7 14,0
200 24,3 20,6 22,2 23 15,2
250 31,5 26,4 29,5 29,5 16,2
300 40,1 32,7 37 37,2 18,5
350 47,7 39,5 44,8 45,9 17,2
400 56,1 46,7 53,2 55,1 16,8
450 65,1 53,7 61,5 64,2 17,5
500 73,6 61,4 71,1 72,1 16,6
550 83,7 68,8 79,7 82,5 17,8
600 93,8 77,2 89 94,1 17,7
650 102 86,7 99 106,1 15,0
700 110 96,6 107,1 118 12,2
750 120,8 103,5 117 132,5 14,3
800 131,2 113,9 127 139,1 13,2


(lower is better)

Thursday, October 31, 2013

Coaxial 9x47 + 10x60 Propellor, 3Cell, Benchmark

The 10x60 inch prop again suprises in a coaxial benchmark. It seems that using a prop with higher pitch on the bottom motor increases the efficiciency. Increasing is in fact not correct, I should say: It minimizes the efficiency loss.

The 9x47+10x60 setup benchmark results are ~ the same as the normal 9x47 benchmark results. 

For my Y6 project I need 225 grams of thrust per motor. That is 450grams of thrust per pair. At 450 grams of thrust there is ~10% efficiency loss between the real benchmark and the theoretical value. 

thrust

(grams)
9x47 + 10x60 benchmark
(watt)
9x47 + 10x60 theoretical
(watt)
9x47 Coaxial benchmark
(watt)
10x60 Coaxial benchmark
(watt)
9x47 + 1060
Theo-Bench
(%)
50 6,4 6,5 6,2 6,6 -1,6
100 12,4 11,8 9,9 12,7 4,8
150 17,7 16,7 15,6 19 5,6
200 23,7 22,8 22,2 26,5 3,8
250 30,2 28,6 29,5 33,2 5,3
300 38,5 34,7 37 41,4 9,9
350 45,9 41,3 44,8 49,9 10,0
400 54,4 48,9 53,2 56,8 10,1
450 62,4 56,3 61,5 65,6 9,8
500 71,1 63,9 71,1 72,7 10,1
550 80,1 71,1 79,7 81,7 11,2
600 89,5 79,7 89 91,4 10,9
650 99,3 88 99 100 11,4
700 107,1 96,9 107,1 109 9,5
750 115,2 104,5 117 118 9,3
800 126,6 114,3 127 125 9,7


(lower is better)

Wednesday, October 30, 2013

Coaxial 9x47 + 10x45 Propellor, 3Cell, Benchmark

This is the first coaxial mixed propellor benchmark. Using a different top and bottom prop might have negative or positive influence on the efficiency. 

"Coaxial 9x47 + 10x45": the first prop will always be the top proller (pull) the second prop will always be the bottom prop (push). So in this case I'm using a small prop on top and a bigger one underneath it. The pitch of both prop is ~ identical.

In the table and graph below I compare the result with the results of the standard coaxial 9x47 setup and the standaard coaxial 10x45 setup. And also the theoratical value of what this combination should perform.

Because the 10x45 coax setup performs less than a 9x47 I expected that the result for this benchmark would be in middle of these two. So no suprise here.

For my Y6 project I need 225 grams of thrust per motor. That is 450grams of thrust per pair. At 450 grams of thrust there is ~15% efficiency loss between the real benchmark and the theoretical value. 


thrust

(grams)
9x47 + 10x45 benchmark
(watt)
9x47 + 10x45 theoretical
(watt)
9x47 Coaxial benchmark
(watt)
10x45 Coaxial benchmark
(watt)
9x47 + 1047
Theo-Bench
(%)
50 6,6 5,6 6,2 6,5 15,2
100 12,1 10,4 9,9 12,5 14,0
150 18,7 15,5 15,6 18,9 17,1
200 24,3 21,5 22,2 26,3 11,5
250 32,5 27,7 29,5 34,3 14,8
300 40,6 34 37 42,8 16,3
350 49,2 41,2 44,8 51,1 16,3
400 57,5 48,6 53,2 58,5 15,5
450 66,4 55,9 61,5 68,5 15,8
500 75,8 64,5 71,1 77,5 14,9
550 84,8 72,6 79,7 88,6 14,4
600 96 82,9 89 99,3 13,6
650 107,2 91,3 99 112,6 14,8
700 114,3 99,3 107,1 122,3 13,1
750 122,6 107,4 117 135 12,4
800 133,8 118 127 145,8 11,8



(lower is better)

Tuesday, October 29, 2013

Coaxial 11x47 Propellor, 3Cell, Benchmark

The benchmark voor the coaxial 11x47 prop is again suprising, but this time in a negative way. Although this prop proved to perform very well in single configuration it turns out that in my coaxial setup it has a huge efficiency loss.

For my Y6 project I need 225 grams of thrust per motor. That is 450grams of thrust per pair. At 450 grams of thrust there is ~20% efficiency loss between the real benchmark and the theoretical value.

thrust

(grams)
11x47 Coaxial benchmark
(watt)
11x47 Coaxial theoretical
(watt)
11x47 pull
x2
(watt)
11x47 push
x2
(watt)
11x47 Coaxial
Theo-Bench
(%)
50 5,4 5,4 5,4 5,4 0,0
100 10,5 9,6 9,6 9,6 8,6
150 16,7 15 15 15 10,2
200 23 19,7 20 19,4 14,3
250 29,5 25,5 26 25 13,6
300 37,2 31,6 32,2 31 15,1
350 45,9 37,6 38,6 36,6 18,1
400 55,1 44,4 45,4 43,4 19,4
450 64,2 51,7 53 50,4 19,5
500 72,1 59,1 60,4 57,8 18,0
550 82,5 66,4 68 64,8 19,5
600 94,1 73,6 74,8 72,4 21,8
650 106,1 82,9 83,4 82,4 21,9
700 118 93,5 94 93 20,8
750 132,5 99,4 99,8 99 25,0
800 139,1 109,6 110 109,2 21,2



(lower is better)

Saturday, October 26, 2013

Coaxial 10x60 Propellor, 3Cell, Benchmark

The benchmark voor the coaxial 10x60 prop is a little bit suprising. Although this prop didn't perform well in single configuration it turns out that in my coaxial setup it is as efficient as the 9x47 coaxial setup and more efficient then the 10x45 coaxial setup.

For my Y6 project I need 225 grams of thrust per motor. That is 450grams of thrust per pair. At 450 grams of thrust there is ~9% efficiency loss between the real benchmark and the theoretical value.

thrust

(grams)
10x60 Coaxial benchmark
(watt)
10x60 Coaxial theoretical
(watt)
10x60 pull
x2
(watt)
10x60 push
x2
(watt)
10x60 Coaxial
Theo-Bench
(%)
50 6,6 7,3 7,6 7 -10,6
100 12,7 13,2 13,8 12,6 -3,9
150 19 19,4 21,2 17,6 -2,1
200 26,5 25,8 27,8 23,8 2,6
250 33,2 32 34,6 29,4 3,6
300 41,4 38,2 41,4 35 7,7
350 49,9 44 47,8 40,2 11,8
400 56,8 51,7 55,6 47,8 9,0
450 65,6 58,8 62 55,6 10,4
500 72,7 66,4 70 62,8 8,7
550 81,7 73,8 78,2 69,4 9,7
600 91,4 81,6 85,8 77,4 10,7
650 100 90,1 95,2 85 9,9
700 109 98,3 103 93,6 9,8
750 118 106 111 101 10,2
800 125 116,1 122,2 110 7,1


(lower is better)

Friday, October 25, 2013

Coaxial 10x45 Propellor, 3Cell, Benchmark

Now it's time to bench the 10x45 props in coaxial configuration. It seems that the efficiency loss is higher then with the 9x47 coaxcial configuration. This was expected because in single prop configuration the 10x45 also performed less efficient then the 9x47 prop.

For my Y6 project I need 225 grams of thrust per motor. That is 450grams of thrust per pair. At 450 grams of thrust there is ~16% efficiency loss between the real benchmark and the theoretical value.

thrust

(grams)
10x45 Coaxial benchmark
(watt)
10x45 Coaxial theoretical
(watt)
10x45 pull
x2
(watt)
10x45 push
x2
(watt)
10x45 Coaxial
Theo-Bench
(%)
50 6,5 5,5 5,8 5,2 15,4
100 12,5 10,6 11,4 9,8 15,2
150 18,9 16,3 17,4 15,2 13,8
200 26,3 22,6 24 21,2 14,1
250 34,3 28,9 30,2 27,6 15,7
300 42,8 35,3 37 33,6 17,5
350 51,1 42,1 44,2 40 17,6
400 58,5 49,7 52,2 47,2 15,0
450 68,5 56,6 58,4 54,8 17,4
500 77,5 65,8 67,6 64 15,1
550 88,6 75,1 77,8 72,4 15,2
600 99,3 85,5 87,2 83,8 13,9
650 112,6 94,5 97,4 91,6 16,1
700 122,3 102,7 107 98,4 16,0
750 135 110,6 114,4 106,8 18,1
800 145,8 121,4 125,4 117,4 16,7

(lower is better)

Wednesday, October 23, 2013

Coaxial 9x47 Propellor, 3Cell, Benchmark

Here is the first set of results for my coaxial benchmarks.  A little bit of explanation:

The column called "9x47 Coaxial benchmark" are the real test result for 2 motors in coaxial configuration. 
The column called "9x47 Coaxial theoretical" is the sum of 1 x 9x47 pull and 1 x 9x47. I added this column the check the % difference between the coaxial real benchmark results and what theoretical would be possible with 2 coaxial motors if there was no efficiency loss.
The column called "9x47 pull x2" is to compare the difference with 2 pull motors side by side.
The column called "9x47 push x2" is to compare the difference with 2 push motors side by side.

For my Y6 project I need 225 grams of thrust per motor. That is 450grams of thrust per pair. At 450 grams of thrust there is ~9% efficiency loss between the real benchmark and the theoretical value.


thrust

(grams)
9x47 Coaxial benchmark
(watt)
9x47 Coaxial theoretical
(watt)
9x47 pull
  x2
(watt)
9x47 push
x2
(watt)
9x47 Coaxial
Theo-Bench
(%)
50 6,2 5,5 6 5 11,3
100 9,9 10,6 11 10,2 -7,1
150 15,6 15,7 15,8 15,6 -0,6
200 22,2 21,3 21,8 20,8 4,1
250 29,5 27,1 27,8 26,4 8,1
300 37 33,4 34,4 32,4 9,7
350 44,8 40,4 42,4 38,4 9,8
400 53,2 48,6 50 47,2 8,6
450 61,5 55,9 57 54,8 9,1
500 71,1 63,7 65 62,4 10,4
550 79,7 71,5 72,8 70,2 10,3
600 89 80,6 82 79,2 9,4
650 99 89,3 91 87,6 9,8
700 107,1 97,9 100,2 95,6 8,6
750 117 106 108 104 9,4
800 127 116,2 118,6 113,8 8,5
(lower is better)

Tuesday, October 8, 2013

tractor VS pusher comparison

So here is the comparison table of all my current pusher en puller propellers. All previous tests on the brushless AX-2210N RC motor with diffent propeller sizes on a 3 cell battery. I would like to test some 12 inch props and a 9x6 but I don't have these props at the moment.

(lower is better, e.g. red line is most efficient)
(this image was updated on 29/12/13: added the 9x6 prop benchmark)

As you can see the red line gives the best overall performance. The 11 inch prop is the most efficient. 

The difference between  a pusher prop and puller prop from the same size is clearly noticeable. But it is not enough to convert a standard quad with motors on top of the arms to a quad with motor underneath the arms. With the 9 inch prop you will gain  5% of efficiency when mounting your motors upside down. But to achieve this you need bigger landing gears. This adds weight to your quad and cancels out the benefit of the gained thrust efficiency.

Mounting 11 inch prop instead of 9 inch props will also give me 8% more efficiency. But because it's not really safe to oversize the prop I currently don't take the risk. The motor will always run warm and  lifetime will be shorter.

(this image was updated on 29/12/13: added the 9x6 prop benchmark)



Saturday, October 5, 2013

11x47 Propellor, 3Cell, Benchmark

Next prop is a 11 inch Hobbyking Slow Fly Electric Prop 11X4.7

Like the 10 inch props this 11 inch propellor is also oversized in combination with this motor on a 3 cell lipo. So it is not safe to use this prop at maximum power. For this prop I have the same motor temperature remark as for the 10 inch Slow Fly prop. It looks like the 11 inch prop is more efficient then the 9 inch prop at the thrust  I need to hover in my current Y6 copter project.

The difference between puller and pusher configuration is ~4% .
The values in bold at 225 gram thrust is what I need for my current Y6-copter project.
Test is performed with a 12V power supply (= 3Cell lipo battery).

Thrust
grams
11x47 pull
watt
11x47 push
watt
push-pull
%
25 2,7 2,7 0,0
50 4,8 4,8 0,0
75 7,5 7,5 0,0
100 10 9,7 3,0
125 13 12,5 3,8
150 16,1 15,5 3,7
175 19,3 18,3 5,2
200 22,7 21,7 4,4
225 26,5 25,2 4,9
250 30,2 28,9 4,3
275 34 32,4 4,7
300 37,4 36,2 3,2
325 41,7 41,2 1,2
350 47 46,5 1,1
375 49,9 49,5 0,8
400 55 54,6 0,7