| 1. |
- Dai, Daoxin, et al.
(författare)
-
Calculation of the spectral response of an arrayed-waveguide gating demultiplexer with a wide-angle beam propagation method in a cylindrical coordinate system
- 2004
-
Ingår i: Optical and quantum electronics. - : Springer Science and Business Media LLC. - 0306-8919 .- 1572-817X. ; 36:11, s. 967-979
-
Tidskriftsartikel (refereegranskat)abstract
- The spectral response of an arrayed-waveguide grating (AWG) demultiplexer is calculated by simulating the field propagation in the output section of an AWG with a wide-angle beam propagation method (BPM) in a cylindrical coordinate system. As in a practical design of an AWG demultiplexer, each output waveguide consists of two straight sections connected by a bending section. The spectral response obtained by the present algorithm is more accurate than those obtained with two popular approximate methods, namely, the conventional overlapped integral method and the standard BPM for radially straight and infinitely long output waveguides. With the present algorithm, the dependence of the spectral response on the parameters of the output section is analyzed. The channel crosstalk and the 3 dB passband width of the spectral response depend mainly on the length of the first straight section, the end separation and the angular separation of the output waveguides. The bending section results in an asymmetrical spectral response with remarkable sidelobes which can be reduced by increasing the bending radius.
|
|
| 2. |
- Dai, X W, et al.
(författare)
-
Pyrolysis of waste tires in a circulating fluidized-bed reactor
- 2001
-
Ingår i: Energy. - 0360-5442 .- 1873-6785. ; 26:4, s. 385-399
-
Tidskriftsartikel (refereegranskat)abstract
- Using a circulating fluidized bed (CFB) as the main reactor, an integrated process development unit was operated aiming at the pyrolysis of waste tires. The main chemical processes in the CFB can be divided into two zones corresponding to pyrolysis and secondary reactions. The pyrolysis of tire powder was carried out at various pyrolysis temperatures, particle sizes of tire powder and feed positions. The effects of temperature, residence time and heating rate on pyrolysis were analyzed based on the experimental data. The main trends are that (1) a long residence time contributes to secondary reactions and (2) lower temperature and heating rate favor carbonization, which reduces the oil yield. Analysis of the pyrolytic oil shows that the predominant components are aromatics, followed by alkanes, non-hydrocarbons and asphalt.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- Zhang, Wennan, et al.
(författare)
-
Process simulation of circulating fluidized beds with combustion/gasification of biomass.
- 2002
-
Ingår i: Twelfth European Biomass Conference - Biomass for Energy, Industry and Climate Protection. - Florence : ETA. - 889004425X ; , s. 1503-
-
Konferensbidrag (refereegranskat)abstract
- This paper briefly presents the work carried out for the 4th framework Joule project under the contract JOR3CT980306. The project is to build up an integrated mathematical model to predict reactor performance of biomass circulating fluidized bed boiler/gasifier when reactor design, operating conditions and fuel properties are defined. For CFB boilers, the sub-models of combustion, heat transfer, ash deposition on a heat transfer surface and NOx/N2O emission have been developed, and evaluated against the 12 MW Chalmers CFB boiler. For CFB gasifiers, the sub-models of gasification, heat transfer, NH3/HCN emission, alkali ash and tar emissions from the gasifiers are developed. The results have been checked on Sanya 6MW industrial biomass CFB gasifier.
|
|
