BEGIN:VCALENDAR

VERSION:2.0

PRODID:-//wp-events-plugin.com//6.6.4.4//EN

TZID:Asia/Jerusalem

X-WR-TIMEZONE:Asia/Jerusalem
BEGIN:VEVENT

UID:0-439@aerospace.technion.ac.il

DTSTART;TZID=Asia/Jerusalem:20170426T163000

DTEND;TZID=Asia/Jerusalem:20170426T173000

DTSTAMP:20230530T181200Z

URL:https://aerospace.technion.ac.il/events/reduced-system-order-and-sensi
 ngactuation-resolution-for-estimation-and-control-of-transition-to-turbule
 nce-2/

SUMMARY:Reduced System Order and Sensing/Actuation Resolution  for Estimati
 on and Control of Transition to Turbulence
DESCRIPTION:Lecturer:Aaron Friedman\n Faculty:Department of Aerospace Engin
 eering\n Institute:Technion – Israel Institute of Technology\n Location:
 Classroom 165\, ground floor\, Library\, Aerospace Eng.\n Zoom: \n Abstrac
 t: \n Details: \n Skin drag in shear flows can be significantly reduced by
  maintaining laminar versus turbulent flow\, rendering the control or dela
 y of transition to turbulence of engineering interest. Controlling transit
 ion from laminar to turbulent plane Poiseuille flow serves as a model prob
 lem for more geometrically complex or realistic shear flows\, such as boun
 dary layers or pipe flow. In previous numerical studies\, application of a
  linear systems approach to controlling transition to turbulence in plane 
 Poiseuille flow has been shown to increase transition thresholds by at lea
 st several factors\, depending on the type of flow perturbation assumed. G
 enerally speaking\, these studies have two primary shortcomings: large mod
 el order and assuming a continuum\, or near continuum\, of wall-mounted se
 nsors and actuators.\n\nThis research attempts to address the aforemention
 ed shortcomings and progress toward physically realizable actuation and se
 nsing. Performance is measured by searching for controlled and uncontrolle
 d transition thresholds in a pseudo-spectral direct numerical simulation (
 DNS) of the Navier-Stokes equations written in-house. Firstly\, our resear
 ch examines the degree to which peak transition threshold improvement can 
 still be obtained both by controlling only a narrow range of wave-number p
 airs and by using sparsely distributed discrete actuators under the assump
 tion of full-state feedback. Secondly\, we investigate the use of sparsely
  distributed discrete sensors\, which relies upon the assumption that only
  a narrow range of wave-number pairs is of interest for state estimation a
 nd control\, and apply a heretofore unused technique for filtering the eff
 ects of sensor spillover caused by deliberate undersampling: state-augment
 ation. Finally\, the use of sparsely distributed actuators and sensors tog
 ether is tested against spatially continuous actuation and sensing\, demon
 strating the transition threshold performance recovery ability of state-au
 gmentation for filtering spillover effects.
CATEGORIES:Seminars
LOCATION:Classroom 165\, ground floor\, Library\, Aerospace Eng.

END:VEVENT

BEGIN:VTIMEZONE

TZID:Asia/Jerusalem

X-LIC-LOCATION:Asia/Jerusalem

BEGIN:DAYLIGHT

DTSTART:20170324T030000

TZOFFSETFROM:+0200

TZOFFSETTO:+0300

TZNAME:IDT

END:DAYLIGHT

END:VTIMEZONE
END:VCALENDAR