Hovercraft B/C

User avatar
rc2000
Member
Member
Posts: 16
Joined: November 10th, 2017, 9:39 pm
State: -
Contact:

Re: Hovercraft B/C

Postby rc2000 » February 13th, 2018, 10:07 pm

Would anyone mind recommending me some DC motors & props for lift. I've really been struggling with it. For thrust I plan on using a computer fan.

Also: Im using 2 of these https://www.amazon.com/1600mAh-Battery- ... +volt+nimh to power my hovercraft. Any tips on connecting them?

kinghong1970
Member
Member
Posts: 89
Joined: November 11th, 2015, 3:27 pm
Division: B
State: NJ
Contact:

Re: Hovercraft B/C

Postby kinghong1970 » February 14th, 2018, 4:43 am

search amazon for mini tamiya connector male

or cut the connector and solder

https://www.amazon.com/s/ref=nb_sb_noss ... ector+male

RestingDoll
Member
Member
Posts: 32
Joined: September 14th, 2016, 5:10 am
Division: C
State: PA
Contact:

Re: Hovercraft B/C

Postby RestingDoll » February 14th, 2018, 4:59 am

jajefan wrote:
nicholasmaurer wrote:
RestingDoll wrote:
The issue is that nothing in the problem indicates that Poiseuille Equation should be applied (viscosity, laminar flow, etc).


I think that is a fair criticism. The ES agreed he should have given more information to indicate the Poiseuille equation was needed. I think his assumption was that most pipes meet the requirements of using Poiseuille: they are reasonably long and not so wide as to generate turbulent flow.


I know this isn't the place to get clarifications, but are the tests allowed to test content not specifically listed in the rules manual? My concern arises from the fact that under rule 4. b. iv. Fluid Mechanics (Div C), Puiseuille's equation is not listed as a topic. It would be good to know for future competitions, as my team did not prepare adequately for topics outside of those listed for the invitational.


The listed topics are more of a guide rather than a strict set of what can and cannot be tested; even so, I would consider Poiseuille to be a subtopic in viscosity.

reed303
Member
Member
Posts: 69
Joined: October 17th, 2014, 2:44 pm
State: -
Contact:

Re: Hovercraft B/C

Postby reed303 » February 14th, 2018, 5:38 am

kinghong1970 wrote:search amazon for mini tamiya connector male

or cut the connector and solder

https://www.amazon.com/s/ref=nb_sb_noss ... ector+male


For those who might be unfamiliar or unable to solder wires, "wire nut" connectors like these are useful
https://www.lowes.com/pd/Utilitech-25-P ... /999953854
Strip off about 3/8" of insulation , and twist the wires together with the connector. The gray or blue size should work for most hovercraft wiring. They also make re-wiring very easy.
Div B Asst Coach 2012-2018

User avatar
Jake R
Member
Member
Posts: 16
Joined: November 16th, 2014, 5:53 pm
Division: B
State: TX
Contact:

Re: Hovercraft B/C

Postby Jake R » February 15th, 2018, 10:07 pm

I know that you need a high static pressure for lift fans, but does cfm matter for list as well? for example, i found this one that i might use https://www.digikey.com/product-detail/ ... ND/5230580 is that a good choice for lift? (max load)
event placing(a space means different competitions.) invitationals/regionals/state

2016 year:
Texas wildflowers: 1st 1st 3rd/1st/coming up
experimental design: 19th 6th/3rd/coming up
roller coaster: 1st 2nd/5th/coming up

placed 3rd in triple e (warm bodied) at ut invitational

User avatar
QuantumEcho
Member
Member
Posts: 31
Joined: September 26th, 2017, 4:57 pm
State: -
Contact:

Re: Hovercraft B/C

Postby QuantumEcho » February 17th, 2018, 10:53 am

Does anyone know how long on average it takes for a SOINC.org FAQ to be answered?
Seven Lakes Junior High ‘17, Obra D. Tompkins High School ‘21

geniusjohn5
Member
Member
Posts: 85
Joined: January 18th, 2017, 6:57 pm
Division: C
State: -
Contact:

Re: Hovercraft B/C

Postby geniusjohn5 » February 17th, 2018, 2:54 pm

Jake R wrote:I know that you need a high static pressure for lift fans, but does cfm matter for list as well? for example, i found this one that i might use https://www.digikey.com/product-detail/ ... ND/5230580 is that a good choice for lift? (max load)


CFM barely matters compared to static pressure when it comes to lift fans. Taking a look at the fan you provided in the link, I think that fan looks effective.
The physicist says, "In the universe, does matter really matter?"
The chemist replies, "I shall find a solution."

LittyWap
Member
Member
Posts: 69
Joined: March 22nd, 2017, 1:44 pm
Division: C
State: PA
Contact:

Re: Hovercraft B/C

Postby LittyWap » February 17th, 2018, 3:29 pm

Hey all,

I was wondering if anyone had any fluid mechanics/Div C practice tests. I was less than satisfied with mine and my partner’s performance at a recent tournament despite having the best build score, (16.89s, 16 rolls). Does anyone have any tests from fargone tournaments; your Physics II homework, anything at all?! I need to really power wash the cobwebs out of my brain.
Build score of 49.88/50 at Nationals!? Slacker! :evil:

Shady Side Academy Division C

Hovercraft, Thermodynamics, Chemistry Lab, Mat Sci

Free Thermo Test: https://adobe.ly/2Dnfrhu

Big P

User avatar
Adi1008
Moderator
Moderator
Posts: 423
Joined: December 6th, 2013, 1:56 pm
Division: Grad
State: TX
Location: Austin, Texas
Contact:

Re: Hovercraft B/C

Postby Adi1008 » February 17th, 2018, 4:25 pm

LittyWap wrote:Hey all,

I was wondering if anyone had any fluid mechanics/Div C practice tests. I was less than satisfied with mine and my partner’s performance at a recent tournament despite having the best build score, (16.89s, 16 rolls). Does anyone have any tests from fargone tournaments; your Physics II homework, anything at all?! I need to really power wash the cobwebs out of my brain.

You could probably find solid fluid mechanics questions in any introductory physics textbook, like Giancoli or Halliday and Resnick
University of Texas at Austin '22
Seven Lakes High School '18
Beckendorff Junior High '14

IvanGe
Member
Member
Posts: 129
Joined: September 29th, 2016, 1:56 pm
Division: B
State: NY
Location: GJHS
Contact:

Re: Hovercraft B/C

Postby IvanGe » February 17th, 2018, 5:40 pm

QuantumEcho wrote:
Does anyone know how long on average it takes for a SOINC.org FAQ to be answered?


it takes a while but if it's over a couple weeks then your question was probably discarded.
2016-2019 Gelinas Science Olympiad // Senior Captain
LISO/Rustin/Cornell/Regionals/States/Nationals
Battery Buggy : 4/-/-/-/-/-
ELG : 14 :cry: /-/-/-/-/-
Fossils : 1/-/-/-/-/-
Potions and Poisons : 3/-/-/-/-/-

geniusjohn5
Member
Member
Posts: 85
Joined: January 18th, 2017, 6:57 pm
Division: C
State: -
Contact:

Re: Hovercraft B/C

Postby geniusjohn5 » February 18th, 2018, 6:24 am

What affects the effectiveness of a fan more? Amperage or Voltage? I'm deciding between a 1600 mah 8.4 nimh battery and a 3000 mah 8.4 nimh battery.
The physicist says, "In the universe, does matter really matter?"
The chemist replies, "I shall find a solution."

dmis
Member
Member
Posts: 64
Joined: November 1st, 2017, 5:44 pm
State: -
Contact:

Re: Hovercraft B/C

Postby dmis » February 18th, 2018, 7:42 am

geniusjohn5 wrote:What affects the effectiveness of a fan more? Amperage or Voltage? I'm deciding between a 1600 mah 8.4 nimh battery and a 3000 mah 8.4 nimh battery.


Oh boy... I think you have a bit of a misunderstanding of both of those concepts. Both current (amperage) and voltage will have an effect on the effectiveness of the fan, but the current through the fan is not really dependent on the capacity (amount of energy of the battery). Notice that when you mention the "amperage" of each battery there is an h after the ma. That means miliamp hours. The addition of the hours to the unit changes the meaning of the term. The battery with the 3000 mah will run longer before needing to be recharged, while the 1600 will run out faster. The 3000 may also be slightly faster/more powerful, due to the lower internal resistance of the battery. I would assume those effects to be largely negligible, unless the fan you have is rated for a lot of current (more than 5A).

MattChina
Member
Member
Posts: 180
Joined: February 12th, 2017, 8:06 am
Division: B
State: NY
Location: somewhere over the rainbow
Contact:

Re: Hovercraft B/C

Postby MattChina » February 18th, 2018, 10:00 am

rc2000 wrote:Would anyone mind recommending me some DC motors & props for lift. I've really been struggling with it. For thrust I plan on using a computer fan.

Also: Im using 2 of these https://www.amazon.com/1600mAh-Battery- ... +volt+nimh to power my hovercraft. Any tips on connecting them?

I would just buy connectors and solder them to the fan. I think its better not to solder anything directly to the battery.
Physics is my city

2017 events: Hovercraft, Ecology, Optics, Write it do it, Fast Facts, Mystery Design(NY trial)
2018 events: Hovercraft, Ecology, Optics, Thermodynamics, Quiz bowl(NY trial)

Ankles moister than a humid summer day

geniusjohn5
Member
Member
Posts: 85
Joined: January 18th, 2017, 6:57 pm
Division: C
State: -
Contact:

Re: Hovercraft B/C

Postby geniusjohn5 » February 18th, 2018, 11:42 am

Can anybody provide a link for connectors? I'm trying to find a way to connect the 8.4 v NiMH battery pack to the rest of my circuit.
The physicist says, "In the universe, does matter really matter?"
The chemist replies, "I shall find a solution."

dmis
Member
Member
Posts: 64
Joined: November 1st, 2017, 5:44 pm
State: -
Contact:

Re: Hovercraft B/C

Postby dmis » February 18th, 2018, 11:55 am

geniusjohn5 wrote:Can anybody provide a link for connectors? I'm trying to find a way to connect the 8.4 v NiMH battery pack to the rest of my circuit.


There are tons of different types, each with advantages and disadvantages. Amazon, ebay, hobbyking, other hobby shops, etc. Some examples to look up are xt60, turnigy connectors (or mini-turnigy connectors) banana plugs, or Dean's connectors. You could also use quick connect crimp terminals.


Return to “2018 Lab Events”

Who is online

Users browsing this forum: No registered users and 1 guest