Abstract: In this work study the location of interface in a stirred vessel with a Concave impeller by computational fluid dynamic was presented. To modeling rotating the impeller, sliding mesh (SM) technique was used and standard k-ε model was selected for turbulence closure. Mean tangential, radial and axial velocities and also turbulent kinetic energy (k) and turbulent dissipation rate (ε) in various points of tank was investigated. Results show sensitivity of system to location of interface and radius of 7 to 10cm for interface in the vessel with existence characteristics cause to increase the accuracy of simulation.
Abstract: We demonstrate a 1×4 coarse wavelength
division-multiplexing (CWDM) planar concave grating
multiplexer/demultiplexer and its application in re-configurable
optical add/drop multiplexer (ROADM) system in silicon-on-insulator
substrate. The wavelengths of the demonstrated concave grating
multiplexer align well with the ITU-T standard. We demonstrate a
prototype of ROADM comprising two such concave gratings and four
wide-band thermo-optical MZI switches. Undercut technology which
removes the underneath silicon substrate is adopted in optical switches
in order to minimize the operation power. For all the thermal heaters,
the operation voltage is smaller than 1.5 V, and the switch power is
~2.4 mW. High throughput pseudorandom binary sequence (PRBS)
data transmission with up to 100 Gb/s is demonstrated, showing the
high-performance ROADM functionality.