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    李东岳

    目前就是这个疑问,2D以及2.5D(轴对称网格)的拉格朗日算法,怎么处理体积分数的计算问题?

  • toposet之后出现空集。。。

    OpenFOAM
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    @学流体的小明 在 toposet之后出现空集。。。 中说:

    感觉是topoSet选择网格,提取各种面的时候有些问题了,我没用过这方面的功能,不太了解。
    你如果只是想把边界面提取出来的话,在blockMesh当中就可以设置吧。

    @李东岳 在 toposet之后出现空集。。。 中说:

    豁牙子注意一下toposet点位置的精度。

    感谢两位大佬提点,豁牙子问题解决了...

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    YungY

    ICEM用block画的多个区域,怎么各自设置成单独的part?

  • 大家发朋友圈越来越少了

    CFD彩虹条
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    @李东岳 这两年的学生真的是过的没劲。。

  • 从.msh文件中获得几何文件

    Meshy
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    李东岳

    感谢分享 楼主好人 :xiexie: :xiexie:

  • DPMFoam、MPPICFoam以及CFDEM怎么选择?

    OpenFOAM
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    M

    @田畔的风 感谢您的回复 可以咨询一下您如果我使用mppic方法时还可以怎么样发生粒子相变吗 我目前想实现水滴入射时发生蒸气相变

  • 湍流模型计算层流转变为湍流

    Algorithm
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    李东岳

    我碰巧最近在看这方面的工作,打算在OKS课进行植入,中文还对不上,但是应该就是楼上说的 转捩模型。我参考的是Menter的文章A One-Equation Local Correlation-Based Transition Model,他们的参考案例也很有意思,T3A系列,单独用层流、湍流都不行,只能用附加转变的模型。下图:

    捕获.JPG

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    两月三年

    我用17.2版本的话,图形显示区 title 显示的字体特别小,还挤在一起,模拟过程中显示多个windows窗口的话还不好找,都给挤没见了,用户体验越来越不好了

  • ParaView的Python脚本使用方法

    OpenFOAM
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    L

    有没有前辈使用过ParaView脚本编辑图片,需要实现自定义图例和坐标轴,超过4位数的坐标和图例刻度值需要表示为例如:10,000样式,即三位一个逗号分隔。请问各位有没有实现过?

  • 用户指南第1章和第2章怎么打不开了?

    OpenFOAM
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    C

    @李东岳 谢谢哥,现在OK了

  • 有关ICEM中的非结构网格加密

    Meshy
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    Y

    计算域是否对称,可否切出1/3生成网格后旋转

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    P

    英国谢菲尔德大学(The University of sheffield)Energy2050团队(http://energy2050.ac.uk)在招一个做CFD方向的全奖博士,做旋转填料床反应器捕捉二氧化碳的CFD仿真研究,对此职位感兴趣的研究生或者优秀本科毕业生可以申请(可直博),目前的申请截止日期是2022年7月22日(可能推迟),如来不及,入学时间可推迟到明年一月。

    谢菲尔德大学,世界百强名校,著名的CFD仿真软件Fluent的发源地,课题组学术氛围很好,适合静心搞科研。课题组在CFD领域有几十年的研究基础,在CCUS领域有丰富的研究资源,课题紧扣国内火热的"双碳"主题,该细分方向组里有7年的研究基础了,可以在前人的基础上接着做。

    具体招聘信息如下:
    We have a fully funded PhD studentship and look for applicants open to both UK and international students: Engineering doctorate (EngD): Predicting performance of intensified carbon capture inside rotating packed beds using CFD modelling

    If you know any good students from China, or the UK, please encourage them to apply.
    Any questions then let them to contact Professor Lin Ma: https://www.sheffield.ac.uk/mecheng/people/academic/lin-ma

    The advert is on findaphd.com: https://www.findaphd.com, search for the project 搜索 predicting performance of intensified carbon capture inside rotating packed beds using cfd modelling。

    或直接通过以下链接:https://www.findaphd.com/phds/project/engineering-doctorate-engd-predicting-performance-of-intensified-carbon-capture-inside-rotating-packed-beds-using-cfd-modelling/?p145128#opennewwindow

    Please make sure that they apply through the university of sheffield website: https://www.sheffield.ac.uk/postgraduate/phd/apply/applying.

    课题介绍:

    Carbon capture is considered the only technology able to decarbonise the hard-to-abate industries. many of these industries utilise legacy sites with little space for large new unit operations required in conventional carbon capture. rotating packed beds (RPB) look to solve this problem by intensifying carbon capture and reducing the footprint required by up to ten times, while also significantly decreasing the capital cost of these units. when combined with proprietary solvents, it is believed the cost of capture can be reduced to $30/tonne CO2 in some cases, helping to enable the rapid uptake of carbon capture and progression towards net zero.

    RPB are a novel technology that utilise the principles of process intensification to enhance the performance of mass transfer processes between fluids. given the application of rpb to the field of CO2 capture is relatively new, there is uncertainty regarding the impact of different process variables on the performance of the rpb that would otherwise require a significant amount of practical experimentation to investigate. computational fluid dynamics can enable the process to be accurately modelled, allowing for quick and inexpensive prediction of performance under various conditions.

    In this project a rotating packed bed absorber will be modelled in ansys fluent, with validation of the model’s outputs through use of the 1 tonnes of co2 per day (TPD) pilot-scale rotating packed bed absorber at the university of sheffield’s translational energy research centre. Initial research will involve investigating the impact of operational conditions and physical properties of the solvent on capture performance. As the project continues, the scope will widen to include sensitivity analysis of design parameters and the impact of scaling the RPB absorber on the existing project outputs and learnings. Additionally, further rotating unit operations could also be investigated.

    This project will utilise and develop your knowledge surrounding CFD modelling, mass and heat transfer, reaction kinetics and chemical equilibria. You will work closely with carbon clean, a global leader in the development of carbon capture technology and pioneers in the use of RPB for industrial decarbonisation. Your findings could directly impact the design and operation of commercial working carbon capture facilities, supporting the pathway to net zero.

    We are seeking applicants to start in september 2022.

    The project will be part of the EPSRC-supported centre for doctoral training in resilient decarbonised fuel energy systems. The student who undertakes it will be one of a cohort of over 50 students in a broad range of disciplines across the universities of sheffield, nottingham and cardiff.

    The research work will be based in the energy research group within the department of mechanical engineering and the translational energy research centre (TERC) at sheffield which is a brand new, high profile, innovation focused national research facility. You will be working within an exciting and dynamic group with approximately over 60 researchers undertaking a broad area of energy research with approximately three years' extensive research time in industry, preparing for high-level careers in the energy sector.

    Funding notes
    The studentship will cover full university fees and a tax-free, enhanced annual stipend of £20,352, including £16,062 (2022/2023) a year for four years and a stipend enhancement of £3,750 per annum.

    英国的全奖机会非常少,机会难得,欢迎各位优秀的CFDer申请!

  • 双欧拉求解液固两相流

    Algorithm
    7
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    U

    @东岳 请问东岳老师有关于双欧拉解决相变问题的例子吗,附带算例内没有找到有关相变的设置

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    用STARCCM做船舶阻力分析,考虑升沉和纵倾,之前流域底部设置为速度入口,结果会收敛。考虑浅水效应即流域底部的影响时,我把底部的边界条件修改为壁面 结果不收敛 且提示如图警告-the mesh may have non-positive volume cells,请问前辈是壁面条件不能修改为壁面而是其他,还是修改为壁面后需要再修改其他的地方,谢谢![替代文字](图片地IMG_20190419_170601.jpg 址)

  • breaking wave下的气泡直径

    Algorithm
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    李东岳

    在breaking wave领域,这种海浪结构,会将空气卷吸并形成很多小气泡。最近提交一个稿件,审稿人推荐我们讨论一下这方面的研究。我详细看了一下,确实有点意思。

    看下图,一些实验研究已经证明,这种海浪拍打过程卷吸进的气泡具有尺寸分布。见过很多文献,都是用的DNS直接模拟研究的,结果也都能证实。

    但目前我想的是,能否用PBE模型,或者其他类似模型做相关的研究。

    捕获.JPG

    气泡直径和分布的关系
    捕获.JPG

    一些参考文献

    Deike, L., Melville, W. K. & Popinet, S. 2016. Air entrainment and bubble statistics in breaking waves. J. Fluid Mech. 801, 91–129.
    Wang, Z., Yang, J., Stern, F., 2016. High-fidelity simulations of bubble, droplet and spray formation in breaking waves. J. Fluid Mech. 792, 307–327.
    G. Soligo, A. Roccon, and A. Soldati, Breakage, coalescence and size distribution of surfactant-laden droplets in turbulent flow, J. Fluid Mech. 881, 244 (2019).
    Ahmed, Z., Izbassarov, D., Costa, P., Muradoglu, M., Tammisola, O. 2020. Turbulent bubbly channel flows: Effects of soluble surfactant and viscoelasticity, Computers & Fluids 212, 104717.

  • 0 赞同
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    S

    @ghuaa 好的,谢谢回复!

  • icoFoam中压力泊松方程

    Algorithm
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    李东岳

    同理,下述网页中都需要处理$\sum_f p_f^{t}\bfS_f$为$\frac{1}{V_\rP}\sum_f p_f^{t}\bfS_f$,均已更正,谢谢

    http://dyfluid.com/rhoPimpleFoam.html
    http://dyfluid.com/rhoSimpleFoam.html
    http://dyfluid.com/simplefoam.html

  • 并行计算报错

    OpenFOAM
    3
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    Y

    @李东岳 感谢老师回复,我的是课题组服务器,应该是有48核心的。我用GPT教的测试并行c程序是可以成功运行的,但是openfoam每个案例都有并行问题。不知道怎么搞

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    来看看

  • 根据节点ID号来设置监测点

    Fluent
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    L

    节点如果是一个监测坐标 那么他一般会固有在一个网格内 那么你只要编写一个算法 根据这个坐标来获取这个cell的id就可以了
    但是在并行下 这个cell_id是要包含在你的thread_id 还有你的cpu_id之下的 相信你对这块是比较了解的
    最后 我们所说的压力 其实都是通过插值法来计算的 你如果想要得出比较精准的压力值 需要采用结构网格 并且在压力离散上 采用QUICK格式
    确保上述之后 最后只要把你的所落cell的压力值 也就是C_P(c,t)输出就行 这些方法就很多了 可以用UDMI作为一个后处理输出 也可以导入成为一个自定义的标量
    最一般的方法 可以通过一个并行的节点传递给node0 然后node0传递到host 由host打印输出