We present a new approach based on the multi-trench technique to improve the electrical performances, which are the fill factor and the electrical efficiency. The key idea behind this approach is to introduce a new mu...We present a new approach based on the multi-trench technique to improve the electrical performances, which are the fill factor and the electrical efficiency. The key idea behind this approach is to introduce a new multi-trench region in the intrinsic layer, in order to modulate the total resistance of the solar cell. Based on 2- D numerical investigation and optimization of amorphous SiGe double-junction （a-Si：H/a-SiGe：H） thin film solar cells, in the present paper numerical models of electrical and optical parameters are developed to explain the impact of the multi-trench technique on the improvement of the double-junction solar cell electrical behavior for high performance photovoltaic applications. In this context, electrical characteristics of the proposed design are analyzed and compared with conventional amorphous silicon double-junction thin-film solar cells.展开更多
沟道敷设具有易于检修和利于电缆散热等优点,但是在实际的敷设过程中存在施工部门不按国标要求杂乱敷设的情况,对电力电缆的温度场分布和载流量产生不利的影响。采用COMSOL有限元仿真软件研究110 k V和35 k V交联聚乙烯电缆在沟道敷设...沟道敷设具有易于检修和利于电缆散热等优点,但是在实际的敷设过程中存在施工部门不按国标要求杂乱敷设的情况,对电力电缆的温度场分布和载流量产生不利的影响。采用COMSOL有限元仿真软件研究110 k V和35 k V交联聚乙烯电缆在沟道敷设条件下回路数、排列间距和排列方式对电缆温度场分布和载流量的影响。结果表明,回路数和排列间距对载流量有显著影响:减少回路数有助于提高沟道内部散热性能,从而提高载流量;当排列间距减小时,载流量逐渐降低,尤其当间距小于电缆半径时减少幅度更加明显。不同电压等级电缆不等间距敷设于同一沟道会降低电缆的载流量,对低电压等级电缆载流量的影响更为显著。多回路电缆不规则混杂敷设于沟道时,温度分布极不均匀,各电压等级电缆的载流量均有明显下降。展开更多
林区道路崎岖,沟壑极多,壕沟是其中一种极限工况,跨越壕沟能力的高低反映了集材机通过性能的强弱。利用Solidworks和Recur Dyn软件对集材机虚拟样机及其可更换三角形履带行动装置进行建模,用Recur Dyn软件对集材机在不同预张紧力、速度...林区道路崎岖,沟壑极多,壕沟是其中一种极限工况,跨越壕沟能力的高低反映了集材机通过性能的强弱。利用Solidworks和Recur Dyn软件对集材机虚拟样机及其可更换三角形履带行动装置进行建模,用Recur Dyn软件对集材机在不同预张紧力、速度及工作状态(空载、装车和集材)下的跨越壕沟能力进行动力学仿真分析。研究结果表明:以预张紧力为24 k N(车重50%)跨越壕沟时,集材机运行更为稳定;预张紧力过大(38.4 k N)或过小(14.4 k N)均会导致履带断链。集材机在跨越壕沟时,速度不应低于14 rad/s,适当地提高速度有助于集材机跨越更宽的壕沟,但速度越大对履带性能要求也越高。多功能集材机空载时跨越的壕沟宽度不应超过900mm,装车时不应超过800 mm,集材时不应超过1 100 mm。展开更多
A multi-scale numerical method coupled with the reactor,sheath and trench model is constructed to simulate dry etching of SiO_2 in inductively coupled C_4F_8 plasmas.Firstly,ion and neutral particle densities in the r...A multi-scale numerical method coupled with the reactor,sheath and trench model is constructed to simulate dry etching of SiO_2 in inductively coupled C_4F_8 plasmas.Firstly,ion and neutral particle densities in the reactor are decided using the CFD-ACE＋ commercial software.Then,the ion energy and angular distributions（IEDs and IADs） are obtained in the sheath model with the sheath boundary conditions provided with CFD-ACE＋.Finally,the trench profile evolution is simulated in the trench model.What we principally focus on is the effects of the discharge parameters on the etching results.It is found that the discharge parameters,including discharge pressure,radio-frequency（rf） power,gas mixture ratios,bias voltage and frequency,have synergistic effects on IEDs and IADs on the etched material surface,thus further affecting the trench profiles evolution.展开更多
飞速增长的光通信容量需求推动着光纤技术的发展,基于空分复用技术的多芯光纤作为突破传统单模光纤容量限制的方法引起了广泛的关注.本文将纤芯异质结构与低折射率沟槽结合,设计了1种具有低串扰的十九芯单模光纤结构,该结构由环绕沟槽的...飞速增长的光通信容量需求推动着光纤技术的发展,基于空分复用技术的多芯光纤作为突破传统单模光纤容量限制的方法引起了广泛的关注.本文将纤芯异质结构与低折射率沟槽结合,设计了1种具有低串扰的十九芯单模光纤结构,该结构由环绕沟槽的3种不同参数的纤芯按正六边形排布构成,在C+L波段能实现稳定单模传输.研究结果表明:在波长为1.55μm时,通过在沟槽中进行掺氟处理,可以使光纤的芯间串扰降低至–39.52 d B/100 km.此外在弯曲半径为100 mm时,弯曲损耗为–7.7×10^(–5) d B/m且色散低于24 ps/(nm·km).纤芯中基模的有效模场面积约为80μm2,有利于降低非线性效应.与传统单模光纤及单沟槽同质结构光纤相比,该结构具有更低的串扰、更好的抗弯曲性能和更大的模场面积.本文设计的光纤适用于空分复用系统中远距离大容量的传输.展开更多
基金supported by the Agence Thématique de Recherche en Sciences et Technologie(ATRST),Government of Algeria,under Grant Pro Thème/87/2015
文摘We present a new approach based on the multi-trench technique to improve the electrical performances, which are the fill factor and the electrical efficiency. The key idea behind this approach is to introduce a new multi-trench region in the intrinsic layer, in order to modulate the total resistance of the solar cell. Based on 2- D numerical investigation and optimization of amorphous SiGe double-junction （a-Si：H/a-SiGe：H） thin film solar cells, in the present paper numerical models of electrical and optical parameters are developed to explain the impact of the multi-trench technique on the improvement of the double-junction solar cell electrical behavior for high performance photovoltaic applications. In this context, electrical characteristics of the proposed design are analyzed and compared with conventional amorphous silicon double-junction thin-film solar cells.
文摘沟道敷设具有易于检修和利于电缆散热等优点,但是在实际的敷设过程中存在施工部门不按国标要求杂乱敷设的情况,对电力电缆的温度场分布和载流量产生不利的影响。采用COMSOL有限元仿真软件研究110 k V和35 k V交联聚乙烯电缆在沟道敷设条件下回路数、排列间距和排列方式对电缆温度场分布和载流量的影响。结果表明,回路数和排列间距对载流量有显著影响:减少回路数有助于提高沟道内部散热性能,从而提高载流量;当排列间距减小时,载流量逐渐降低,尤其当间距小于电缆半径时减少幅度更加明显。不同电压等级电缆不等间距敷设于同一沟道会降低电缆的载流量,对低电压等级电缆载流量的影响更为显著。多回路电缆不规则混杂敷设于沟道时,温度分布极不均匀,各电压等级电缆的载流量均有明显下降。
文摘林区道路崎岖,沟壑极多,壕沟是其中一种极限工况,跨越壕沟能力的高低反映了集材机通过性能的强弱。利用Solidworks和Recur Dyn软件对集材机虚拟样机及其可更换三角形履带行动装置进行建模,用Recur Dyn软件对集材机在不同预张紧力、速度及工作状态(空载、装车和集材)下的跨越壕沟能力进行动力学仿真分析。研究结果表明:以预张紧力为24 k N(车重50%)跨越壕沟时,集材机运行更为稳定;预张紧力过大(38.4 k N)或过小(14.4 k N)均会导致履带断链。集材机在跨越壕沟时,速度不应低于14 rad/s,适当地提高速度有助于集材机跨越更宽的壕沟,但速度越大对履带性能要求也越高。多功能集材机空载时跨越的壕沟宽度不应超过900mm,装车时不应超过800 mm,集材时不应超过1 100 mm。
基金supported by National Natural Science Foundation of China(No.11375040)the Important National Science&Technology Specific Project of China(No.2011ZX02403-002)
文摘A multi-scale numerical method coupled with the reactor,sheath and trench model is constructed to simulate dry etching of SiO_2 in inductively coupled C_4F_8 plasmas.Firstly,ion and neutral particle densities in the reactor are decided using the CFD-ACE＋ commercial software.Then,the ion energy and angular distributions（IEDs and IADs） are obtained in the sheath model with the sheath boundary conditions provided with CFD-ACE＋.Finally,the trench profile evolution is simulated in the trench model.What we principally focus on is the effects of the discharge parameters on the etching results.It is found that the discharge parameters,including discharge pressure,radio-frequency（rf） power,gas mixture ratios,bias voltage and frequency,have synergistic effects on IEDs and IADs on the etched material surface,thus further affecting the trench profiles evolution.
文摘飞速增长的光通信容量需求推动着光纤技术的发展,基于空分复用技术的多芯光纤作为突破传统单模光纤容量限制的方法引起了广泛的关注.本文将纤芯异质结构与低折射率沟槽结合,设计了1种具有低串扰的十九芯单模光纤结构,该结构由环绕沟槽的3种不同参数的纤芯按正六边形排布构成,在C+L波段能实现稳定单模传输.研究结果表明:在波长为1.55μm时,通过在沟槽中进行掺氟处理,可以使光纤的芯间串扰降低至–39.52 d B/100 km.此外在弯曲半径为100 mm时,弯曲损耗为–7.7×10^(–5) d B/m且色散低于24 ps/(nm·km).纤芯中基模的有效模场面积约为80μm2,有利于降低非线性效应.与传统单模光纤及单沟槽同质结构光纤相比,该结构具有更低的串扰、更好的抗弯曲性能和更大的模场面积.本文设计的光纤适用于空分复用系统中远距离大容量的传输.
