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    A

    乒乓球带坑可能就变更更更贵了:tishizi:

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    幻想de罗卜

    @两月三年 good ,好主意。我试试哈。

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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!

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    李东岳

    放点图有利于讨论..

  • 求助柱面网格质量差的问题

    Meshy
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    AlexA

    我认为这个是和几何无关的,衡量网格质量的参数中有一个叫aspect ratio,这个值为1时最好,像那种类似薄片或者细长的网格,这个值会很大,这种网格一般质量很差。

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    C

    @blookcfd
    你好,感谢回复。

    我发现我的问题可能是由于snappyHexMesh选定的区域与重叠区域重合导致的,现在已经解决了。

    但是也有没解决的部分,我自己在原来overset网格的基础上加了一点东西,自己编译了另一个lib,这个lib与SHM还是有点冲突,运行的时候会报错,但实际上SHM执行了,网格也能用,所以我下一步好好看看我自己编的lib哪里有问题。

    当用toposet + createPatch时,提示找不到stl文件,但是我的stl文件就在对应文件夹下放着,所以这个问题我还没找到原因。

    我还在找寻替代方法,如果您知道其他方法能把stl放入计算域中,请不吝赐教,谢谢。

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    L

    @下里巴人 最近稍微试了一下均匀流下粗糙网格的3组试验,一组时间步长给定为旋转2度的时间,一组为0.2度,一组Fluent自调整。因为时间原因仅做了一小段时间内的对比(未达到稳定周期性变化),关注的两个物理量(一个轴向力,一个转矩)在三组试验中趋势几乎一致,数值误差小于3%.另外对一种非均匀流下的精细网格进行了同样的试验(同样时间较短),趋势几乎一致,但不如均匀流下趋势符合得那么好,误差在9%以内。
    受时间限制,对比不严谨,仅作为前期考察

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    U

    谢谢您的回答,fluent里不是只有压力和密度求解器吗,问题有些浅显,不要见怪。还有怎么设置流体域为真空。

  • foam-extend的fsiFoam并行效率问题

    OpenFOAM
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    五好青年

    @number44 在 foam-extend的fsiFoam并行效率问题 中说:

    foam-extend的icoFsiFoam

    您好,请问下,下面两者有什么区别呢?
    foam-extend中自带的icoFsiFoam

    单独的fsiFoam

  • 分块求助

    Meshy
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    潘大志

    看了一下你的模型,之所以你在相贯线处网格画不好,这主要问题在于你的几何模型——相贯线与底面相切,出现了三角区域。从而导致网格在该三角区域网格质量奇差无比。如下图所示

    该问题导致出现了如下问题:

    解决的办法是将底面拉伸一段距离,避免出现相贯线与底面相切即可,如下图所示
    0_1536142189833_4ccfa31a-f8b8-4435-87b6-c322423cd7e1-image.png
    如此,便可愉快的进行分块和关联
    0_1536142304777_9fb3a5ee-3695-47f4-971f-61fe9c119d23-image.png
    接着对其进行O型块划分
    0_1536142342178_11fb8b28-9d22-441a-978f-e0f2d4ed1c7c-image.png
    最终网格效果图如下
    0_1536142436479_986e33bd-8587-4ee0-a010-5f914675e718-image.png

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    D

    本算例采用的是气液两相流,想要给空气相加一个速度边界条件,而水相不加这个边界条件,下面给出的这个边界条件是空气相的,是依时的边界条件,按照网站上相似的做法编了以下,但是始终出现如下错误。请各位老师同学有时间帮忙解答一下,非常感谢!
    下面是边界条件:

    afInlet { type codedFixedValue; value $internalField; redirectType ramp; name sinewave; code #{ #include <math.h> scalar t = this->db().time().value(); fvPatchField<vector> u ( patch().lookupPatchField<volVectorField,vector>("U.air") ); u[t] = vector(0,0,2*3.1416*10/1000/0.77*1*sin(2*3.1416*1*t)); (*this) == u; #};

    下面是报错的内容:

    --> FOAM FATAL ERROR: request for volVectorField U from objectRegistry region0 failed available objects of type volVectorField are 8 ( HbyA.air U.air U.water U.air_0 KdUByA.air U.water_0 KdUByA.water HbyA.water ) From function const Type& Foam::objectRegistry::lookupObject(const Foam::word&) const [with Type = Foam::GeometricField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh>] in file /home/dyfluid/OpenFOAM/OpenFOAM-8/src/OpenFOAM/lnInclude/objectRegistryTemplates.C at line 211. FOAM aborting #0 Foam::error::printStack(Foam::Ostream&) at ??:? #1 Foam::error::abort() at ??:? #2 Foam::GeometricField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh> const& Foam::objectRegistry::lookupObject<Foam::GeometricField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh> >(Foam::word const&) const in "/home/dyfluid/OpenFOAM/OpenFOAM-8/platforms/linux64GccDPInt32Opt/bin/multiphaseEulerFoam" #3 Foam::totalPressureFvPatchScalarField::updateCoeffs() at ??:? #4 Foam::fvMatrix<double>::fvMatrix(Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&, Foam::dimensionSet const&) in "/home/dyfluid/OpenFOAM/OpenFOAM-8/platforms/linux64GccDPInt32Opt/bin/multiphaseEulerFoam" #5 ? in "/home/dyfluid/OpenFOAM/OpenFOAM-8/platforms/linux64GccDPInt32Opt/bin/multiphaseEulerFoam" #6 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6" #7 ? in "/home/dyfluid/OpenFOAM/OpenFOAM-8/platforms/linux64GccDPInt32Opt/bin/multiphaseEulerFoam" Aborted (core dumped)
  • Apple M1 OpenFoam8

    CFD彩虹条
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    L

    @lgw https://github.com/gerlero/openfoam-app/tree/v1.8.4

  • 大家做模拟用MATLAB多吗?

    CFD彩虹条
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    P

    @jerry 来的有点晚了,下载不了了。能给个书名吗?谢谢

  • snappyHexMesh画内部网格

    Meshy
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    Z

    @chengan-wang 你好,请问你说少了一个定义是啥?我好像遇到了和你一样的问题,先谢谢啦。

  • OpenFOAM中重叠网格问题Suggar++?

    OpenFOAM
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    五好青年

    Any information would be extremely helpful!

  • volScalarField的函数计算

    OpenFOAM
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    X

    @hongjiewang 请问你是在这步Clapeyron方程用局部压力计算饱和温度吗?还有这里的饱和压力pSat是个变量吗?

  • 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。。

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    应该可以写udf输出吧

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    T

    是不是udf里面没有保存运动的数据

  • 关于周期性边界的入口流量设置问题

    Fluent
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    我的模型是计算一个泵的外特性以及泵的内部流场,这个泵由一个叶轮加一个导叶组成,叶轮叶片数为3,导叶叶片数为4,现在为了加快计算速度,采用了周期性边界,选取了一片叶轮加一片导叶来计算,所以这个流量的大小应该怎么设置?