To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
In this paper the development and flight testing of flapping-wing propelled, radio-controlled micro air vehicles are described. The unconventional vehicles consist of a low aspect ratio fixed-wing with a trailing pair of higher aspect ratio flapping wings which flap in counterphase. The symmetric flapping-wing pair provides a mechanically and aerodynamically balanced platform, increases efficiency by emulating flight in ground effect, and suppresses stall over the main wing by entraining flow. The models weigh as little as 11g, with a 23cm span and 18cm length and will fly for about 20 minutes on a rechargeable battery. Stable flight at speeds between 2 and 5ms–1 has been demonstrated, and the models are essentially stall-proof while under power. The static-thrust figure of merit for the device is 60% higher than propellers with a similar scale and disk loading.
Hot-wire anemometer measurements in a plane jet issuing at a harmonically oscillating angle into a moving air stream have been made to aid the understanding of oscillatory jet flows in general and flow past aerofoils with oscillating jet flaps in particular. The rates of velocity decay and jet spreading are shown to be greater and less, respectively, than those for a steady jet parallel to the air stream. The shapes of instantaneous velocity profiles and limited measurements of turbulence intensity are similar to those for a steady jet in a parallel air stream if a correction is made for the small velocity difference across the curved jet. The motion of the jet centre-line indicates that flow path lines are similar to those for a steady jet flap over a significant range of frequency of jet oscillation. Finally, a quasi-steady jet flap theory is proposed for an analytical description of the major flow features.
Email your librarian or administrator to recommend adding this to your organisation's collection.