Wattflyer RC Network: RC Universe :: RCU Magazine :: RCU Forums :: RCU Classifieds :: RCU User Reviews :: RCU YouTube
Home Who's Online Calendar Today's Posts RealTime Post Spy Mark Forums Read
Go Back   WattFlyer RC Electric Flight Forums - Discuss radio control eflight > Electric R/C Airplanes > Electric Ducted Fan Jets
Register Members List Wattflyer Extras Articles Search Today's Posts Mark Forums Read Social Groups

Electric Ducted Fan Jets Discuss electric ducted fan jets here including setup tips, power systems, flying techniques, etc.

Thank you for your support (hide ads)
Thread Tools Display Modes
Prev Previous Post   Next Post Next
Old 06-14-2014, 10:54 AM   #1
Super Contributor
quorneng's Avatar
Join Date: Jul 2008
Location: Cheshire, UK
Posts: 1,685
Thanked 57 Times in 56 Posts
Club: A lone flyer!
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award 
iTrader: (0)
Friends: (6)
Default Cascade ducting

The Harrier/AV8 uses cascade 'vectoring' nozzles.
Click image for larger version

Name:	Nozzles3.jpg
Views:	278
Size:	155.7 KB
ID:	176063
Whilst I have no intention (at this stage!) to build a VTOL plane I wondered if it would be possible to use this principle to have multiple nozzles on a single EDF but built very light (in Depron?) to keep to a 'scale' size.
First a 'test' duct to work out the best way to actually make it. For simplicity the ducting is square with a double cascade. Each cascade vane is made of 0.015" litho plate.
Click image for larger version

Name:	Dcascade1.JPG
Views:	197
Size:	109.2 KB
ID:	176064
Two cascade units joined together to form a twin nozzle.
The inlet side.
Click image for larger version

Name:	TwinInlet.JPG
Views:	164
Size:	109.6 KB
ID:	176065
The outlets.
Click image for larger version

Name:	TwinCmplt.JPG
Views:	181
Size:	92.1 KB
ID:	176066
The complete duct unit weighs just 0.2oz (5.9g)
Coupled to my 'spare' 55mm EDF on a thrust test rig the object is find out what, if anything, actually happens.
Click image for larger version

Name:	ThrustTest.JPG
Views:	186
Size:	98.0 KB
ID:	176067
A run up on a 3s.

It generate 9.1oz thrust drawing 20A
On the same rig with the complete nozzle assembly removed the fan generate 18oz thrust.
Although this result appears rather disappointing the total area of the nozzles is only 54% of the FSA so some reduction in static thrust would be expected.

The next step is to build a four nozzle test duct with a combined nozzle area equal to the FSA.

quorneng is online now  
  Reply With Quote

  WattFlyer RC Electric Flight Forums - Discuss radio control eflight > Electric R/C Airplanes > Electric Ducted Fan Jets

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Motor For 81" OV-10D NOGS Bronco Flite-Metal Warbird Electrics 25 09-01-2013 03:16 PM

All times are GMT +1. The time now is 09:19 PM.

Powered by: vBulletin
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright 2005 WattfFlyer.com
RCU Eflight HQ

Charities we support Select: Yorkie Rescue  ::  Crohn's & Colitis Foundation

Page generated in 0.19853 seconds with 76 queries