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The product structure of aero-engine is very complex,and its engineering change is frequent,so it is difficult to realize the real-time and accurate definition of design configuration by using the traditional parts list management mode or simply replacing the parts list with engineering bills of material(EBOM). In this paper,the configuration management experience of WZ16 engine and EC175 transmission systems is summarized,and the effectiveness configuration function of Teamcenter system is studied. From the perspective of facilitating model serialization development and configuration management,a single management method of aero-engine design configuration based on EBOM is proposed,and the configuration management of a certain civil turboshaft engine is performed with preliminary verification. The results show that the method can effectively improve the control efficiency and accuracy of the design configuration.

The characteristics of directional couplers and power splitters based on three-guide optical couplers in slot waveguide structures are analyzed in detail by a three-dimensional full-vectorial beam propagation method. The numerical results show the achievement of a compact three-guide directional coupler operating as polarization independent with a length of 58.0 [micro]m and having almost evenly spaced propagation constants of the three lowest order modes for quasi-TE and quasi-TM modes. Thus, a high coupling efficiency from one outside waveguide to the other outside waveguide is demonstrated and is over 99.5% for both polarization states. For a three-guide power splitter, multiple sets of waveguide parameters for achieving polarization-independent operation are presented. Tolerances to operating wavelength and structural parameters are also analyzed, and the evolution of the injected field along the propagation distance through the proposed devices is demonstrated. OCIS codes: 130.3120, 230.7380, 130.2790, 250.5300.

On-chip Bragg gratings with high reflectivities have been found to have widespread applications in filters, resonators, and semiconductor lasers. However, achieving strong Bragg reflections with flat response across a broad bandwidth on the popular 220 nm silicon-on-insulator (SOI) platform still remains a challenge. In this paper, such a high performance device is proposed and fabricated, which is based on a slot waveguide with gratings etched on the inner sidewalls of the slot. By manipulating the local field in the slot region using a chirped and tapered grating-based mode transition, the device achieves a flat response with ultra-high reflection and low transmission for the TE mode across a broad operating bandwidth. Leveraging the ultra-high birefringence of the SOI waveguide, the device functions both as a TE slot waveguide reflector and a TM pass polarizer. Simulation results demonstrate that the device exhibits an ultra-high rejection of more than 50 dB and a reflectivity exceeding 0.99 for the TE mode across a 91 nm wavelength range, while maintaining a high transmittance of larger than 0.98 for the TM mode. Experimental results validate that the device performance is consistent with the simulation results. A fabricated device based on such a gratings exhibits a low insertion loss (<0.8 dB) and high polarization extinction ratio (>30 dB) over 100 nm bandwidth (1484 nm-1584 nm), demonstrating that the performance of the present design is competitive with that of the state-of-the-art SOI Bragg gratings.

A compact and broadband silicon-based polarization beam splitter (PBS) is proposed and investigated in detail, where the two arms of the directional coupler (DC) are, respectively, embedded with subwavelength gratings (SWGs) and vertical slots so that field distributions for the TE mode are significantly changed, effectively weakening coupling strength, whereas those for the TM mode are almost unaffected, nearly analogous to the DC with strip waveguides. By carefully optimizing structural parameters, efficient coupling will emerge between the two waveguides for the TM mode, while TE mode will be confined in the SWG-assisted strip waveguide. Consequently, the two modes can be effectively separated, and thus the realization of a PBS is accomplished. Results show that a compact PBS with a coupling length of 6.45 µm is achieved, together with the extinction ratio (ER) of 27.54/31.88 dB, the insertion loss of 0.12/0.14 dB, and the reflection loss of -43.67/-30.50 d B , respectively, for TE/TM mode at the wavelength of 1.55 µm. The bandwidth, for both modes, is up to 230/100 nm when ER is larger than 15/20 dB. In addition, fabrication tolerances to the critical structural parameters and field evolution through the proposed device are analyzed.