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炼油厂氢网络超结构优化方法的改进及应用 被引量:2
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作者 孟凡忠 苏建海 陈春凤 《炼油技术与工程》 CAS 2021年第9期16-19,共4页
在用超结构建模方法优化废氢流股回收网络时,往往会遇到模型求解难度大,甚至无法得到最优解的情况。将废氢流股中组分表征为氢气、可凝轻烃和燃料气3种资源,建立三角坐标表征,探讨资源回收优化方法,由此形成物料平衡及流股走向的相应约... 在用超结构建模方法优化废氢流股回收网络时,往往会遇到模型求解难度大,甚至无法得到最优解的情况。将废氢流股中组分表征为氢气、可凝轻烃和燃料气3种资源,建立三角坐标表征,探讨资源回收优化方法,由此形成物料平衡及流股走向的相应约束,并结合数学建模方法建立了一种改进的超结构优化模型。用某炼油厂案例对该模型进行验证,结果表明:同等计算条件下,常规建模方法和改进建模方法分别运算5.3 s和1.6 s后获得计算结果;前者对部分流股的去向优化并未达到最优,获得了次优解,而改进方法计算速度更快,并获得最佳匹配网络;两者的经济效益分别为1063,2144万元/a,后者较前者获得了1081万元/a的超额收益。 展开更多
关键词 炼油厂 氢网络 超结构优化 废氢流股 目标函数 约束条件
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炼厂氢气优化实践与经济评价 被引量:2
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作者 孟凡忠 霍姗 +2 位作者 王兵 张英 张龙 《炼油技术与工程》 CAS 2021年第8期32-35,共4页
采用氢夹点技术对J石化全厂氢气网络进行问题诊断,发现其Ⅱ重整产氢位于夹点之上。用PROⅡ对重整氢直供加氢装置进行模拟计算,并开展Ⅱ重整氢直供下游管网的实际操作优化。对优化方案的可行性和经济性进行评价和论证,结果表明:在不影响... 采用氢夹点技术对J石化全厂氢气网络进行问题诊断,发现其Ⅱ重整产氢位于夹点之上。用PROⅡ对重整氢直供加氢装置进行模拟计算,并开展Ⅱ重整氢直供下游管网的实际操作优化。对优化方案的可行性和经济性进行评价和论证,结果表明:在不影响下游加氢装置的前提下,重整氢直供每年可获得经济效益562.10万元。 展开更多
关键词 炼油厂 氢气 夹点 优化 经济评价
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基于GaAs PHEMT工艺的60~90GHz功率放大器MMIC
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作者 孟范忠 薛昊东 方园 《半导体技术》 CAS 北大核心 2021年第3期193-197,共5页
研制了一款60~90 GHz功率放大器单片微波集成电路(MMIC),该MMIC采用平衡式放大结构,在较宽的频带内获得了平坦的增益、较高的输出功率及良好的输入输出驻波比(VSWR)。采用GaAs赝配高电子迁移率晶体管(PHEMT)标准工艺进行了流片,在片测... 研制了一款60~90 GHz功率放大器单片微波集成电路(MMIC),该MMIC采用平衡式放大结构,在较宽的频带内获得了平坦的增益、较高的输出功率及良好的输入输出驻波比(VSWR)。采用GaAs赝配高电子迁移率晶体管(PHEMT)标准工艺进行了流片,在片测试结果表明,在栅极电压为-0.3 V、漏极电压为+3 V、频率为60~90 GHz时,功率放大器MMIC的小信号增益大于13 dB,在71~76 GHz和81~86 GHz典型应用频段,功率放大器的小信号增益均大于15 dB。载体测试结果表明,栅极电压为-0.3 V、漏极电压为+3 V、频率为60~90 GHz时,该功率放大器MMIC饱和输出功率大于17.5 dBm,在71~76 GHz和81~86 GHz典型应用频段,其饱和输出功率可达到20 dBm。该功率放大器MMIC尺寸为5.25 mm×2.10 mm。 展开更多
关键词 GaAs赝配高电子迁移率晶体管(PHEMT) 功率放大器(PA) 平衡式放大器 单片微波集成电路(MMIC) E波段
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PROPER CONDITIONS OF MESHING FOR Hy-Vo SILENT CHAIN AND SPROCKET 被引量:16
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作者 meng fanzhong LI Chun CHENG Yabing 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第4期57-59,共3页
Proper meshing of Hy-Vo silent chain and sprocket is important for realizing the transmission of the silent chain with more efficiency and less noise. Based on the study of the meshing theory of the Hy-Vo silent chain... Proper meshing of Hy-Vo silent chain and sprocket is important for realizing the transmission of the silent chain with more efficiency and less noise. Based on the study of the meshing theory of the Hy-Vo silent chain with the sprocket and the roll cutting machining principle of the sprocket with the hob, the proper conditions of the meshing for the Hy-Vo silent chain and the sprocket are put forward with the variable pitch characteristic of the Hy-Vo silent chain taken into consideration, and the proper meshing design method on the condition that the value of the link tooth pressure angle is unequal to the value of the sprocket tooth pressure angle is studied. Experiments show that this new design method is feasible. In addition, the design of the pitch, the sprocket tooth pressure angle and the fillet radius of the sprocket addendum circle are studied. It is crucial for guiding the design of the hob which cuts the Hy-Vo silent chain sprocket. 展开更多
关键词 Hy-Vo silent chain Variable pitch Proper meshing conditions Sprocket tooth pressure angle Sprocket hob Modification coefficient
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MESHING THEORY AND DESIGN METHOD OF NEW SILENT CHAIN AND SPROCKET 被引量:16
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作者 meng fanzhong FENG Zengming CHU Yaxu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第3期425-427,共3页
Based on the study of the meshing theory of a new silent chain and sprockets, and the rolling cutting theory of sprocket and hob, the harmonious relations of dominating dimensions among the new silent chain, sprocket ... Based on the study of the meshing theory of a new silent chain and sprockets, and the rolling cutting theory of sprocket and hob, the harmonious relations of dominating dimensions among the new silent chain, sprocket and hob is build, the meshing conditions are expatiated, and the resolved expression, which can instruct design and calculation, is educed. The tests show that the meshing design method is feasible. 展开更多
关键词 New silent chain Meshing theory Sprocket Involute tooth Sprocket hob Modification coefficient
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WEAR FAILURE MECHANISM AND MULTI-IMPACT PROPERTY OF AUTOMOTIVE ENGINE CHAIN 被引量:12
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作者 meng fanzhong Wang Shukun +2 位作者 Lan Hong Xu Rongjin Xu Hanxue 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期401-404,共4页
The multi-impact characteristics and failure mechanism of two kinds of automotive engine chain made in China are studied through engine assembly and road-drive tests. The worn surface morphologies of rubbing area betw... The multi-impact characteristics and failure mechanism of two kinds of automotive engine chain made in China are studied through engine assembly and road-drive tests. The worn surface morphologies of rubbing area between pin, bush and roller are also analyzed based on scanning electron microscope. The results show that the main wear mechanism of automotive engine chain is fatigue wear, and its failure mechanism is the forming, extending and flaking of cracks on top layer of pin and bush. In addition, the material, hot-treatment method and shaping technique for roller have a great influence upon the resistance to multi-impact. Ensuring sufficient strength and plasticity of roller, as well as adopting suitable shaping technique are the effective method to increase its resistance to multi-impact. 展开更多
关键词 Automotive engine chain Wear mechanism Cold-extruding roller Resistance to multi-impact Cycle performance
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EXPERIMENTAL STUDY ON HIGH-SPEED CHARACTERISTICS OF AUTOMOTIVE ENGINE OIL-PUMP CHAIN 被引量:8
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作者 CHENG Yabing meng fanzhong +1 位作者 XU Hanxue WU Jianming 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第1期36-39,共4页
The high-speed multi-cycle impact and speed, load fluctuant characteristics of a kind of narrow-width automotive engine oil-pump chain 06BN-1 are studied through engine assembly and road-drive tests to satisfy the lig... The high-speed multi-cycle impact and speed, load fluctuant characteristics of a kind of narrow-width automotive engine oil-pump chain 06BN-1 are studied through engine assembly and road-drive tests to satisfy the light-weight demand of engine. The worn surface morphologies of rubbing area between pin, bush and roller are also analyzed based on scanning electron microscope. The results show that the main wear mechanism of automotive engine oil-pump chain is fatigue wear, and it's failure mechanism is the forming, extending and flaking of cracks on top layer of pin and bush. Pin and bush both occurred cycle-soften phenomenon, and roller occurred cycle-harden. Fretting wear is one of the most important "fall to pieces" failure causes of automotive chain. Ensuring sufficient strength and plasticity of roller, as well as adopting suitable shaping technology are the effective methods to increase its resistance to multi-cycle impact. 展开更多
关键词 Automotive engine oil-pump chain Wear mechanism Cycle-soften Cycle-harden Fretting wear Resistance to multi-cycle impact
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