Page 20 of 34

Re: Wind Power B/C

Posted: February 12th, 2017, 6:43 pm
by maxxxxx
I know that what's said on here isn't official, but there is no minimum distance between the blade assembly and the fan during testing right? And since I do want to make the answer official, would it be better to submit a FAQ, or a Rules Clarification?

Re: Wind Power B/C

Posted: February 12th, 2017, 8:17 pm
by kenniky
maxxxxx wrote:I know that what's said on here isn't official, but there is no minimum distance between the blade assembly and the fan during testing right? And since I do want to make the answer official, would it be better to submit a FAQ, or a Rules Clarification?
Last year had a bit in the rules that stated minimum distance; since that isn't there anymore, I think it's safe to assume that there is no minimum distance

Re: Wind Power B/C

Posted: February 13th, 2017, 12:16 am
by pyt1ger
maxxxxx wrote:I know that what's said on here isn't official, but there is no minimum distance between the blade assembly and the fan during testing right? And since I do want to make the answer official, would it be better to submit a FAQ, or a Rules Clarification?
I can't find anything in the rules about minimum distance from fan, but in the competitions I've attended (SoCal) they all have had a minimum distance of around 1-2 inches.

Re: Wind Power B/C

Posted: February 13th, 2017, 4:21 am
by maxxxxx
kenniky wrote:
maxxxxx wrote:I know that what's said on here isn't official, but there is no minimum distance between the blade assembly and the fan during testing right? And since I do want to make the answer official, would it be better to submit a FAQ, or a Rules Clarification?
Last year had a bit in the rules that stated minimum distance; since that isn't there anymore, I think it's safe to assume that there is no minimum distance
That's what I thought, but on Saturday at a comp they used a minimum of 5cm rule and since that was the State ES I wanted to make sure. If I want an official answer should I submit this as a FAQ? I don't want to get to States and have the same problem.

Re: Wind Power B/C

Posted: February 13th, 2017, 5:44 am
by RestingDoll
maxxxxx wrote:
kenniky wrote:
maxxxxx wrote:I know that what's said on here isn't official, but there is no minimum distance between the blade assembly and the fan during testing right? And since I do want to make the answer official, would it be better to submit a FAQ, or a Rules Clarification?
Last year had a bit in the rules that stated minimum distance; since that isn't there anymore, I think it's safe to assume that there is no minimum distance
That's what I thought, but on Saturday at a comp they used a minimum of 5cm rule and since that was the State ES I wanted to make sure. If I want an official answer should I submit this as a FAQ? I don't want to get to States and have the same problem.
I don't think 1 cm vs 5 cm would decrease wind speed by that much. In any case, everyone would be affected the same amount.

Re: Wind Power B/C

Posted: February 13th, 2017, 6:11 am
by maxxxxx
RestingDoll wrote:
maxxxxx wrote:
kenniky wrote: Last year had a bit in the rules that stated minimum distance; since that isn't there anymore, I think it's safe to assume that there is no minimum distance
That's what I thought, but on Saturday at a comp they used a minimum of 5cm rule and since that was the State ES I wanted to make sure. If I want an official answer should I submit this as a FAQ? I don't want to get to States and have the same problem.
I don't think 1 cm vs 5 cm would decrease wind speed by that much. In any case, everyone would be affected the same amount.
I don't think it's fair to assume that everyone would be impacted the same, as there were other discussions earlier in this thread about some turbines not starting because they were positioned too far away. And besides, don't you want the State Supervisor to be following the most current rules? They also didn't tell us our voltage after the testing on each speed(which is bold in the rules) so I think they just need to take another look through the rules. That last sentence may have sounded a little harsh but the people running it were really nice and I don't mean any disrespect, just that it would be beneficial for Supervisors to be more familiar with the rules, which is also why I wanted the distance issue clarified.

Re: Wind Power B/C

Posted: February 13th, 2017, 6:52 am
by Alex-RCHS
I agree with maxxxxx. It wouldn't affect all teams equally because some teams may have spent some time deciding what distance generates the most voltage for each speed. If a team figures out that their turbine runs best at 3 cm, they should be rewarded for that.

Re: Wind Power B/C

Posted: February 13th, 2017, 10:01 am
by RestingDoll
maxxxxx wrote:
RestingDoll wrote:
maxxxxx wrote:
That's what I thought, but on Saturday at a comp they used a minimum of 5cm rule and since that was the State ES I wanted to make sure. If I want an official answer should I submit this as a FAQ? I don't want to get to States and have the same problem.
I don't think 1 cm vs 5 cm would decrease wind speed by that much. In any case, everyone would be affected the same amount.
I don't think it's fair to assume that everyone would be impacted the same, as there were other discussions earlier in this thread about some turbines not starting because they were positioned too far away. And besides, don't you want the State Supervisor to be following the most current rules? They also didn't tell us our voltage after the testing on each speed(which is bold in the rules) so I think they just need to take another look through the rules. That last sentence may have sounded a little harsh but the people running it were really nice and I don't mean any disrespect, just that it would be beneficial for Supervisors to be more familiar with the rules, which is also why I wanted the distance issue clarified.
Conversely, a set distance would give equal power available to be captured regardless if the turbine started or not; similarly, 5 cm does not seem like an outlandish distance. I agree though, event supervisors should be well-versed in the current iteration of the rules, and that probably shouldn't've happened.

Re: Wind Power B/C

Posted: February 14th, 2017, 5:22 am
by ashmmohan
RestingDoll wrote:
maxxxxx wrote:
RestingDoll wrote:
I don't think 1 cm vs 5 cm would decrease wind speed by that much. In any case, everyone would be affected the same amount.
I don't think it's fair to assume that everyone would be impacted the same, as there were other discussions earlier in this thread about some turbines not starting because they were positioned too far away. And besides, don't you want the State Supervisor to be following the most current rules? They also didn't tell us our voltage after the testing on each speed(which is bold in the rules) so I think they just need to take another look through the rules. That last sentence may have sounded a little harsh but the people running it were really nice and I don't mean any disrespect, just that it would be beneficial for Supervisors to be more familiar with the rules, which is also why I wanted the distance issue clarified.
Conversely, a set distance would give equal power available to be captured regardless if the turbine started or not; similarly, 5 cm does not seem like an outlandish distance. I agree though, event supervisors should be well-versed in the current iteration of the rules, and that probably shouldn't've happened.
1 cm vs 5 cm definitely makes a difference; it ups my voltage by about 10 or 20 mV. For high speed, the supervisor at Golden Gate did not let us come within like 3 centimeters, but on low speed we could move it as close as we wanted; it was pretty weird how they facilitated things.

Re: Wind Power B/C

Posted: February 14th, 2017, 8:26 am
by maxxxxx
So at an invite, the test had the following question:
Invitational wrote:Water is stored in a vertical cylinder shaped container on top of a 35 meter tower. The cylinder has a radius

of 12 m and a height of 18 m. The density of water is (1000 kg / m^3). What is the potential energy of the

water stored in the tower?
I did:

U = mgh, m = DV, V = pi*r^2*H

U = (1000*pi*12*12*18)*9.81*35

and ended up with U = 2.8GJ, which was one the multiple choice answers.

The key said the answer was 3.5GJ. Did I do something wrong, or was it a mistake on the answer key?