电阻点焊电极头冷却对流换热数值模拟与分析

电阻点焊是在汽车车身装配过程中应用最广泛的一种焊接工艺,点焊工艺过程的效率依赖于电极头的寿命,而电极头水冷效果的好坏与连续工况下电极头的寿命直接相关.围绕电阻点焊工艺过程中冷却水的冷却作用问题,运用数值模拟的方法,真实地模拟了电极头冷却腔内流体流动的情况,并对冷却水作用和电极头对流换热的问题进行了详尽的分析,为进一步提高电极头水冷效果,延长电极头寿命奠定了基础.     

刀盘结构对水下切粒水室流场分布的影响

对于特殊材料的水下切粒加工,采用立式爪形刀盘的独特结构。运用有限元分析软件fluent,对水下切粒水室进行数值模拟,对比分析立式爪形刀盘与传统刀盘的水室流场分布,探究不同的刀盘结构以及刀盘位置的变化对于切粒水室流场分布的影响。     

某型发动机高温转速不足分析

文章分析了某型发动机在外场点火试车试验中,发动机到达一定的转速后,发动机转速增加缓慢,伺服阀可能产生的原因.重点从系统油压波动、油液温度、液流流态等方面对伺服阀进行了分析.     

超超临界储水罐调节阀及管配系统汽蚀特性分析

针对合川电站超超临界锅炉储水罐调节阀出现的严重汽蚀现象,基于两相空化流动方程和FLUENT流场数值模拟方法,对该调节阀及其管配系统的流场特性进行分析。将模拟结果与实际失效结果相比较并提出优化方案。结果表明:基于FLUENT的空化模型模拟结果与实际工程失效情况比较吻合,加长出口管道至4m后,在三通底板处速度降低71.4%,含汽量降低84.9%。该分析方法对储水罐调节阀设计有较好的指导作用,对促进其国产化进程也有积极意义。     

气流喷射床反应器液体停留时间分布实验与模拟

气流喷射床反应器具有良好的传递性,减少轴向返混,相间接触时间短,气液比(气固比)调节灵活等特点。本文使用脉冲进样法测定了气流喷射床反应器液体的停留时间分布(RTD),并用Fluent软件模拟了实验,初步考察了影响停留时间分布的各因素。结果表明,随着液流量的增大,停留时间逐渐趋于稳定,而气流量对液体停留时间影响较小;Fluent软件得到的模拟值与实验值较吻合,说明模型可用。     

加强型微型热声制冷机谐振管的设计

设计一种高效率的热声制冷机谐振管，采用Fluent流体软件对比渐扩管、直管、渐缩管中的压力，发现渐缩管具有增压作用。设计了1／4波长的谐振管，并调节其声腔使其达到纵向谐振频率状态，以便提高热声制冷机的效率。     

Flow simulation in Electro-Static-Precipitator (ESP) ducts with turning vanes

Flow simulation in inlet ducts along with several turning vanes used in electrostatic precipitator (ESP) are analysed to understand the flow pattern at its exit locations. The geometry of inlet duct has been extracted from the Plant Design Manufacturing System (PDMS) and refined with turning vanes placed at several locations. The domain of duct geometry around turning vanes are decomposed with several volumes and filled with hexahedral elements with the help of stat-of-art mesh generator - Hypermesh. The resulting computational grid has been used in TASCflow solver to predict its flow pattern in the duct. Simulation for the specified conditions predicts uneven flow distribution in the ESP inlet duct. Due to large flow recirculation and turbulent losses in the duct, non-uniform averaged mass flow rates are noticed at duct exit locations. Simulation results suggest that the improvement of flow distribution in the duct through optimization can be tried by placing more turning/splitter vanes in the inlet duct. In order to ensure that the results obtained from TASCflow are meaningful and in right direction, in the absence of measurement data, simulation was benchmarked with other industry standard commercial flow solvers. The observations made from these popular solvers confirm the findings obtained using the TASCflow solver. The analysis with multiple solvers indicates that Fluent provides quick results, while better visualization can be made using CFX solver. The Star-CD solver, which captures the turbulent losses accurately takes more time for convergence provides alternatives.     

基于Fluent的阀门开启过程阀芯气动力仿真研究

利用Fluent动网格和UDF技术对适当简化的阀门2D模型进行数值模拟,得到开启过程中作用在阀芯上的轴向气动力变化规律。     

低功耗超声流量计的研究

针对超声波流量测量中管道结构对测量精度的影响,采用Fluent仿真软件模拟了不同管道中流体的流动状况,对管道内的超声波信号进行了分析和比较,设计了超声波流量传感器,并应用设计的流量传感器,研制了超声波流量积算仪的硬件电路和软件,最终的样机实验结表明,该超声流量计流量误差小于±2%,系统的平均工作电流为35μA。     

袋式除尘器内部湍流流场数值模拟研究

袋式除尘器内部有着复杂的湍流流场,形成的漩涡回流易造成尾部滤袋磨损和破坏。针对这一问题,利用CFD软件对袋式除尘器内部湍流流场分布进行了数值模拟。通过设置入口速度等边界条件,采用k-ε湍流模型模拟气相流动,分析了袋式除尘器内部各处速度流场、气体流场轨迹的情况,为袋式除尘器的改进和设计提供了理论依据。