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Re: Wind Power B/C
Posted: March 3rd, 2017, 6:07 am
by Complexity02
tyasasvi wrote:Btw my binder is not trash, but it is bad compared to Community MS (won 4th in nats last year and same people doing this year). I have barely any chance of beating them, but I still have some hope. We compete in NJ. I want to beat Community really badly, and we had a chance until yesterday when our state made wind power a written exam only which makes it so much harder for us. Also, I have no partner for the event. Can someone plz help me out? We could share our binders, and designs. We got 900 volts without resistance. Plz I'll give designs too. Email
yasasvi321@gmail.com.
Having a great binder is only half the fight. You have to know you binder as well. You have states this weekend, I'm assuming, and the best way to
go IMHO is writing your own notes. I don't see as well why you are trying to beat a nationally placing team in wind power, and I seriously doubt having one of our binders will give you the lead. Following tips given in these forums, such as having formulas, timelines, and a detailed diagram will help. If the test is written, expect many application based problems where formulas will be needed.
Re: Wind Power B/C
Posted: March 3rd, 2017, 12:40 pm
by andrewwski
tyasasvi wrote:Btw my binder is not trash, but it is bad compared to Community MS (won 4th in nats last year and same people doing this year). I have barely any chance of beating them, but I still have some hope. We compete in NJ. I want to beat Community really badly, and we had a chance until yesterday when our state made wind power a written exam only which makes it so much harder for us. Also, I have no partner for the event. Can someone plz help me out? We could share our binders, and designs. We got 900 volts without resistance. Plz I'll give designs too. Email
yasasvi321@gmail.com.
If you want to beat a nationally ranked team, you have to do your own work. Even more generally, if you want to do well, you need to do your own work.
Simply having a good reference doesn't help much if you don't understand what's inside it or how to use it.
You'll figure this out some day.
Re: Wind Power B/C
Posted: March 3rd, 2017, 4:23 pm
by freed2003
Ionizer wrote:freed2003 wrote:When calculating voltage drop with the formula V=RI would you also have to multiply by the wires length?
If you are given resistance, no. If you are given resistivity, yes, you need to factor in the length and cross sectional area of the wire,
R = r*L/A.
what do r and L represent?
Re: Wind Power B/C
Posted: March 3rd, 2017, 4:31 pm
by jonboyage
freed2003 wrote:Ionizer wrote:freed2003 wrote:When calculating voltage drop with the formula V=RI would you also have to multiply by the wires length?
If you are given resistance, no. If you are given resistivity, yes, you need to factor in the length and cross sectional area of the wire,
R = r*L/A.
what do r and L represent?
r is resistivity and L is length
Re: Wind Power B/C
Posted: March 4th, 2017, 5:24 am
by soyuppy
Alex-RCHS wrote:freed2003 wrote:I mean of a rotor
also can someone help me with this question?
A power plant in Chicago is generating 900 MW on a 700 KV line. Assuming the line
is 100 kilometers long, with a resistance along the line of 0.2 ohms, what is the current along the lines
When I use I=V/R I get 3500kA but when I use I=P/V I get 1286 A
I've never heard of that term, but this might help:
https://en.m.wikipedia.org/wiki/Blade_solidity
As for that question, I don't understand either. It seems like a poorly worded question to me. I've also seen other questions on the test that was from that had incorrect answers on the answer key.
A Rotor Solidity is define or can be expressed as: Number of Blade * Surface Area of Each Blade / Swept Area of the Blade. RS is a function of torque. Higher RS, higher Torque. The more blades you slap on the turbine, the more torque need to spin the blade.
Re: Wind Power B/C
Posted: March 5th, 2017, 7:04 pm
by Alex-RCHS
We've found that we get the best score by placing our blade a few cm from the fan, right in the center of the fan. Do other teams have the same results?
Re: Wind Power B/C
Posted: March 7th, 2017, 9:49 am
by d4dd7y00n
Should I make my turbines concave or convex? Also, should I use tape or glue to attach the turbines to the CD?
Re: Wind Power B/C
Posted: March 14th, 2017, 5:24 pm
by StormTJ
I know that scores tend to change based on the fans used, but does anyone have a base line estimate of what i should aim for in terms of scoring?
Re: Wind Power B/C
Posted: March 14th, 2017, 5:31 pm
by ashmmohan
Alex-RCHS wrote:We've found that we get the best score by placing our blade a few cm from the fan, right in the center of the fan. Do other teams have the same results?
Same for me.
Re: Wind Power B/C
Posted: March 14th, 2017, 5:33 pm
by ashmmohan
d4dd7y00n wrote:Should I make my turbines concave or convex? Also, should I use tape or glue to attach the turbines to the CD?
Concave, pitch the blade so that it is in the direction of lifting off of the cd. If it were convex, then the turbine cannot catch the wind from the fan.