Ultrasonic vibration feeding（UVF） method which can quantitatively feed and precisely deposit fine powder is a potential technique for micro feeding.The excitation sources transmit vibration to capillary though the t...Ultrasonic vibration feeding（UVF） method which can quantitatively feed and precisely deposit fine powder is a potential technique for micro feeding.The excitation sources transmit vibration to capillary though the third medium for most UVF devices.The vibrator is directly touched with the capillary can transmit mechanical energy on the capillary as much as possible,and the powder feeding can be controlled more precise.However,there are few reports about it.A direct UVF system which integrates the function of micro feeding,process observing,and powder forming was developed in this work.In order to analyze the effect of the system factors on feeding,a group of L9（3^3） orthogonal experiments are selected to confirm the effect of level change of factors.The three factors are capillary nozzle diameter,amplitude and signal.The flow rate was stable for each combined factors,and the optimum combination for the minimum flow rate are choosing small capillary,small amplitude,and triangular wave orderly.The whole process of feeding includes start point,middle stage and stop stage.Starting of feeding was synchronized to vibration when the amplitude of capillary nozzle is larger than critical amplitude.Then,the feeding process enters the middle stage,the feeding state is observed by the CCD,and it is very stable in the middle stage.Overflow of feeding can＇t be eliminated during the stop stage.The features of the deposited powder lines are analyzed; the overflow can be diminished by choosing small capillary and appropriate ratio of the capillary nozzle diameter to the particle size.Chinese characters lattices were deposited to validate the ability of quantitatively feeding and fixed feeding of UVF.Diameters of all powder dots show normal distribution,and more than 60% dots are concentrated from 550 μm to 650 μm,and the average diameter for all the dots is 597 μm.Most dots positions are well approached to their scheduled positions,and the maximum deviation is 0.27 mm.The new direct UVF system is used to implement experiments,which confirms the precise controllable of feeding.According improve the feeding technique,it suits well for rapid prototyping,chemistry,pharmaceutics and many other fields,which require precise measurement and feed minim powder.展开更多
研究基于DCS(Distributed Control System)的燃气-蒸汽联合循环机组运行智能控制系统,确保机组安全运行的同时,提高机组整体运行效率。构建基于DCS的燃气-蒸汽联合循环机组运行智能控制框架,过程控制层的Mark VI系统、DCS系统根据监测...研究基于DCS(Distributed Control System)的燃气-蒸汽联合循环机组运行智能控制系统,确保机组安全运行的同时,提高机组整体运行效率。构建基于DCS的燃气-蒸汽联合循环机组运行智能控制框架,过程控制层的Mark VI系统、DCS系统根据监测数据变化实现机组设备、旁路等自动控制。SIS层接收联合循环机组监测数据后,将其作为基于深度神经网络故障诊断模型的输入,实现机组设备故障的识别。在检测到故障时触发联锁保护子系统动作,将停机指令下达给自动启停控制子系统,使机组停止运行。实验结果表明,该系统可实现燃气-蒸汽联合循环机组设备故障识别,在100次训练后,训练损失为0.1左右,F-Score指标最大值为0.93;故障工况下,该系统可根据预定逻辑实现燃气-蒸汽联合循环机组自动停机。展开更多
分布式能源系统(distributed energy systems,DES)的运行性能与设备变工况特性密切相关,设备启停控制策略可有效调节DES动态运行特性。为探究设备启停控制策略对DES运行的影响,建立了以最小运行成本为优化目标、考虑能量转换设备启停控...分布式能源系统(distributed energy systems,DES)的运行性能与设备变工况特性密切相关,设备启停控制策略可有效调节DES动态运行特性。为探究设备启停控制策略对DES运行的影响,建立了以最小运行成本为优化目标、考虑能量转换设备启停控制的优化调度模型,并采用Gurobi求解器对该模型进行优化求解。通过将优化结果与未考虑设备启停控制的调度结果进行对比,结果表明:考虑能量转换设备启停控制后,DES一次能源消费量、二氧化碳排放量和运行成本分别降低5.65%,4.72%,4.05%;即使能源价格波动,运行成本减少率、一次能源节约率和二氧化碳减排率仍大于零。由此可见,在分布式能源系统优化调度中引入设备启停控制,有助于改善系统运行性能。展开更多
基金supported by National Hi-tech Research and Development Program of China (863 Program, Grant No. 2008AA03A238)National Natural Science Foundation of China (Grant No. 51005186)Foundation for the Author of National Excellent Doctoral Dissertation of China (Grant No. 2007B39)
文摘Ultrasonic vibration feeding（UVF） method which can quantitatively feed and precisely deposit fine powder is a potential technique for micro feeding.The excitation sources transmit vibration to capillary though the third medium for most UVF devices.The vibrator is directly touched with the capillary can transmit mechanical energy on the capillary as much as possible,and the powder feeding can be controlled more precise.However,there are few reports about it.A direct UVF system which integrates the function of micro feeding,process observing,and powder forming was developed in this work.In order to analyze the effect of the system factors on feeding,a group of L9（3^3） orthogonal experiments are selected to confirm the effect of level change of factors.The three factors are capillary nozzle diameter,amplitude and signal.The flow rate was stable for each combined factors,and the optimum combination for the minimum flow rate are choosing small capillary,small amplitude,and triangular wave orderly.The whole process of feeding includes start point,middle stage and stop stage.Starting of feeding was synchronized to vibration when the amplitude of capillary nozzle is larger than critical amplitude.Then,the feeding process enters the middle stage,the feeding state is observed by the CCD,and it is very stable in the middle stage.Overflow of feeding can＇t be eliminated during the stop stage.The features of the deposited powder lines are analyzed; the overflow can be diminished by choosing small capillary and appropriate ratio of the capillary nozzle diameter to the particle size.Chinese characters lattices were deposited to validate the ability of quantitatively feeding and fixed feeding of UVF.Diameters of all powder dots show normal distribution,and more than 60% dots are concentrated from 550 μm to 650 μm,and the average diameter for all the dots is 597 μm.Most dots positions are well approached to their scheduled positions,and the maximum deviation is 0.27 mm.The new direct UVF system is used to implement experiments,which confirms the precise controllable of feeding.According improve the feeding technique,it suits well for rapid prototyping,chemistry,pharmaceutics and many other fields,which require precise measurement and feed minim powder.
文摘研究基于DCS(Distributed Control System)的燃气-蒸汽联合循环机组运行智能控制系统,确保机组安全运行的同时,提高机组整体运行效率。构建基于DCS的燃气-蒸汽联合循环机组运行智能控制框架,过程控制层的Mark VI系统、DCS系统根据监测数据变化实现机组设备、旁路等自动控制。SIS层接收联合循环机组监测数据后,将其作为基于深度神经网络故障诊断模型的输入,实现机组设备故障的识别。在检测到故障时触发联锁保护子系统动作,将停机指令下达给自动启停控制子系统,使机组停止运行。实验结果表明,该系统可实现燃气-蒸汽联合循环机组设备故障识别,在100次训练后,训练损失为0.1左右,F-Score指标最大值为0.93;故障工况下,该系统可根据预定逻辑实现燃气-蒸汽联合循环机组自动停机。
文摘分布式能源系统(distributed energy systems,DES)的运行性能与设备变工况特性密切相关,设备启停控制策略可有效调节DES动态运行特性。为探究设备启停控制策略对DES运行的影响,建立了以最小运行成本为优化目标、考虑能量转换设备启停控制的优化调度模型,并采用Gurobi求解器对该模型进行优化求解。通过将优化结果与未考虑设备启停控制的调度结果进行对比,结果表明:考虑能量转换设备启停控制后,DES一次能源消费量、二氧化碳排放量和运行成本分别降低5.65%,4.72%,4.05%;即使能源价格波动,运行成本减少率、一次能源节约率和二氧化碳减排率仍大于零。由此可见,在分布式能源系统优化调度中引入设备启停控制,有助于改善系统运行性能。
