考虑AGV运输和机器转速的作业车间绿色调度研究

在车间实际生产中,机器在加工状态和空载状态下都需要消耗能量,且机器在不同转速下的能耗也不同。此外,随着自动导引车(AGV)在车间的广泛应用,其能耗也不可忽略,因此对考虑AGV和机器转速的作业车间绿色调度问题进行研究具有重要意义。完工时间不仅被认为是表示车间生产效率的指标,而且在一定程度上意味着机器空载能耗的减少、机器利用率的提高。为此,对考虑AGV运输和机器转速的作业车间完工时间和能耗优化问题进行了研究。首先,对作业车间机器的能耗、AGV能耗进行了分析,探讨了AGV、工件和机器之间的工艺约束,建立了考虑AGV运输和机器转速的作业车间绿色调度模型;然后,采用两阶段优化的方式分别对完工时间和车间总能耗进行了优化,在第一阶段,机器以最高转速进行了加工,采用改进麻雀搜索算法对其最大完工时间进行了优化;在第二阶段,在保证第一阶段优化得到的完工时间最小值不变的前提下,提出了一种间隙档位调整策略,通过降低部分工序的机器转速来降低车间能源消耗,实现对车间总能耗的优化;最后,采用标准用例对算法进行了仿真实验。研究结果表明:在第一阶段采用改进麻雀搜索算法,提高了种群质量,加快了算法的收敛速度,算法具有较强的跳出局部最优能力;第二阶段在保证完工时间的基础上,采取间隙档位调整策略来降低能耗,通过10个用例测试表明能耗可减少1.13%~5.18%。该结果验证了考虑AGV和机器转速绿色调度模型的正确性以及改进麻雀算法的有效性。

机器多转速的柔性作业车间绿色调度问题

为了减少制造过程中的能耗,从生产运作的角度探讨了如何在制造业生产调度中实现绿色制造。以柔性作业车间调度问题为背景,考虑了机器多转速,在不影响生产进度的前提下通过调节机器转速来实现绿色制造。首先建立了考虑机器多转速的柔性作业车间调度优化模型,构建了能耗计算模型;然后依据带精英策略的非支配排序遗传算法的框架,提出了综合考虑完工时间和能源消耗的低碳调度算法,设计了多种变异方式,提出了精英保留与末位淘汰的选择方式;最后的数值实验结果表明,所提算法能够很好地求解此类问题。

高转速机器基础极限允许振幅的确定

苏联现行的动力机器基础设计规范19-79没有规定转速超过1000转/分的机器的基础极限允许振幅的数值,也没有给出计算方法。而现在这种高速机器设备已得到广泛的应用。现代工业发展的特点,是不断提高设备的功率,同时,对机器的振动提出了更加严格的限制。但是,另一方面,由于力求降低建筑工程的造价和劳动量,因而设备基础的尺寸日趋减小,而且越来越多地采用刚度较小的框架式基础结构。

高转速汽轮鼓风机框架式基础动力模态及结构动反应分析

通过对一汽轮鼓风机框架式基础的动力分析计算，对高转速动力机器框架式基础设计的资料获取，力学模型的选择，计算结果进行了探索和研究，对高转速动力机器框架式基础的设计具有参考价值。

谈动力机器基础设计

简要阐述了近年来国内学者从共振法到振幅法,从平面两自由度法到空间多自由度法,以及轴系与基础的联合动力计算研究动力机器基础设计的部分成果,并对高转速动力机器框架式基础的设计进行了探索和研究,从而为动力机器基础设计积累相关经验。

基于群体免疫算法的绿色车间调度研究

针对机器具有多转速的绿色柔性作业车间调度问题,以最大完工时间最小化和不同转速下的总能耗最小化为优化目标,构建了多转速下的绿色柔性车间调度模型,提出了一种离散的冠状病毒群体免疫算法(discrete coronavirus herd immunity optimizer,DCHIO)进行求解。针对多转速问题解空间较为庞大的特点,引入了离散化的个体更新方式,提出了一种多尺度联合搜索的种群更新机制以快速、均匀地搜索解空间;设计了动态变异操作以增强算法的种群多样性同时实现自适应调整;通过挖掘当前调度方案的经验知识,提出了基于知识驱动的邻域搜索策略,以同时减小最大完工时间和能源消耗。实验结果表明:所提算法可以有效解决多转速绿色柔性调度问题。

基于改进布谷鸟搜索算法的TFT-LCD制造调度方法

针对基于改进布谷鸟搜索算法的TFT-LCD制造cell阶段绿色调度问题,建立了以最小化最大完工时间和碳排放总量为目标的数学模型.采用基于机器选择、转速选择和工序选择的三段式编码,应用在步长因子前加入动态系数的改进布谷鸟搜索算法,结合双元锦标赛和动态淘汰制来构建Pareto最优解集.通过对某车间实际生产数据进行仿真,验证了模型和算法的有效性,仿真结果表明,改进布谷鸟搜索算法在保障最大完工时间的前提下,可以有效的减少碳排放量.

集成工艺规划与车间调度的节能优化方法

为了在柔性作业车间制造过程中实现节能优化,从工艺规划与车间调度集成的角度,提出了集成工艺规划与车间调度的节能优化方法,以降低作业车间的能耗。首先,提出了车间能耗计算方法,构建了以总能耗和完工时间最小的优化目标模型。其次,提出了一种改进的灰狼优化算法,采用一种四层编码方式,设计了新的种群更新方法,并引入交叉算子,对调度模型进行求解。最后,通过作业车间实例验证了上述模型的节能潜力及改进算法的可行性。

Vector control of induction motor based on fractional-order intelligent-integral speed controller

To improve dynamic and static performances and robustness of the induction motor speed control system based on vector control,an improved fractional-order intelligent proportional integral(IPIλ)controller was applied to the speed controller of the vector control system,which combined the intelligent fractional integral with the proportion according to the variation of deviation.Compared with proportional integral(PI)and fractional-order proportional integral(FOPI)controllers,the IPIλcontroller achieved better control performance.The stimulation results indicate that the IPIλcontroller can not only track the given speed quickly and accurately,but also have better anti-interference and robustness for load and parameters variations.

Analysis and active control of low frequency booming noise in car

For Lightweight body,sound radiation and sound insulation performance have negative effects on interior noise by the deterioration of local stiffness and modality.So the research on the active control of vibration and noise for car body panels is useful for engineering.Analysis and active control of booming noise in car is researched by using a new active damping vibration reduction technology named smart constrained layer damping(SCLD).According to the vibration characters of body roof,an optimal placement of actuators is distributed.Based on dSPACE hardware in loop environment,an adaptive active control system is designed.Selecting vibration signals of engine mounting point as the reference input of adaptive controller,an active control experiment of booming noise for mini-car is carried out.Experimental results show that,when the engine speed is at 3700 RPM and4250RPM,the interior booming noise decreases 4.2dB(A),and 3.5dB(A) separately.It proposes new methods and techniques for intelligent control of car body NVH in the future.

对空间框架式基础按平面框架基础作振动计算的讨论

通过计算说明,对机器转速在1 000～3 000 r/min的空间框架式基础采用简化的平面框架计算模型会产生很大的误差。建议在设计中不采用这种简化的计算模型。

Numerical Simulation of Rotating Stall in a Centrifugal Compressor with Vaned Diffuser

This paper reports a numerical study on the process from normal operating conditions to rotating stall in a centrifugal compressor with vaned diffuser. The purpose is to better understand the flow characteristics near stall point under the interactions between centrifugal impeller and vaned diffuser. Numerical results show that under certain conditions just preceding stall point the tip leakage vortex begins to fluctuate at roughly half of the blade passing frequency. This phenomenon is similar to rotating instability in axial compressors. With the flow rate reduced further the impeller stalls and five stall cells propagating at a frequency of 85 percent of impeller rotation speed are found.

A Study of the Unsteady Tip Flow Field of a Transonic Compressor

An experimental investigation on the unsteady tip flow field of a transonic compressor rotor has been performed.The casing-mounted high frequency response pressure transducers were arranged along both the blade chord and the blade pitch.The chord-wise ones were used to indicate both the ensemble averaged and time varying flow structure of the tip region of the rotor at different operating points under 95% design speed and 60% design speed.The pitch-wise circumferential transducers were mainly used to analyze the unsteadiness frequency of the tip leakage flow in the rotor frame at the near stall condition.The contours of casing wall pressure show that there were two clear low pressure regions in blade passages,one along the chord direction,caused by the leakage flow and the other along the tangential direction,maybe caused by the forward swept leading edge.Both low pressure regions were originated from the leading edge and formed a scissor-like flow pattern.At 95% design speed condition,the shock wave interacted with the low pressure region and made the flow field unsteady.With the mass flow reduced,the two low pressure regions gradually contracted to the leading edge and then a spike disturbance emerged.

Numerical Investigation of Rotating Stall in Centrifugal Compressor with Vaned and Vaneless Diffuser

This study presents a numerical simulation of the stall and surge in a centrifugal compressor and presents a description of the stall development in two different cases.The first case is for a compressor with vaneless diffuser and the second is for a compressor with vaned diffuser of the vane island shape.The main aim of this study is to compare the flow characteristics and behavior for the two compressors near the surge operating condition and provide further understanding of the diffuser role when back flow occurs at surge.Results showed that for a location near the diffuser entrance,the amplitude of the static pressure fluctuations for the vaneless diffuser case is higher than that for the vaned diffuser case near surge condition.These pressure fluctuations in the case of the vaneless diffuser appear with a gradual decrease of the mean pressure value as a part of the surge cycle.While for the case of the vaned diffuser,the pressure drop during surge occurs faster than the case of the vaneless diffuser.Also,results indicated that during surge in the case of vaneless diffuser,there is a region with low velocity and back flow that appears as a layer connecting all impeller passages near shroud surface and this layer develops in size with time.On the other hand,for the case of vaned diffuser during surge,the low velocity regions appear in random locations in some passages and these regions expand with time towards the shroud surface.Results showed that during stall,the impeller passages are exposed to identical impact from stall cells in the case of vaneless diffuser while the stall effect varies from passage to another in the case of the vaned diffuser.