权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Mechanisms of particle fouling on structured heat exchanger surfaces

结构化换热器表面颗粒结垢的机制

基本信息

批准号：
268877694
负责人：
Professor Dr.-Ing. Nikolai Kornev
金额：
--
依托单位：
Institut für Chemische und Thermische Verfahrenstechnik
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2015
资助国家：
德国
起止时间：
2014-12-31 至 2022-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/268877694?language=en
关键词：
Mechanisms particle fouling structured heat

项目摘要

Fouling, i.e. the formation of deposits on heat- and/or mass transferring surfaces is a fundamental problem for the design and operation of energy and chemical engineering processes. The resulting economic and ecological damage is enormous. Particulate fouling, the deposition of the suspended particles in the carrier fluid, such as sand or mud (see VDI WA 2006), is together with crystalline fouling the main source of fouling problems. The structured heat exchangers surfaces e.g. ribs, fins or dimples are commonly utilized to increase heat transfer rates while keeping the additional friction losses at a minimum. Staggered dimples show the best possible solution in terms of energy efficiency compared to other vortex generators, since the increase of the heat release is approximately equal to the increase of the frictional resistance. Despite the knowledge about the significance of fouling and the resulting problems during the operation, the maximization of heat transfer and minimization of hydraulic losses are in the foreground in the design process. In the previous research project “Effects of particulate fouling on structured heat transfer surfaces”, the influence of particulate fouling could be analyzed systematically for dimpled surfaces using spatial and temporal highly resolved Euler-Lagrangian Large-Eddy simulations and detailed experimental investigations.Within the proposed follow-up research project it is intended to extend the developed numerical methods by the influence of inter-particle collisions and wall roughness. Based on the simulated local distribution of deposited particles and the integral fouling layer thickness for short fouling intervals, a new multi-scale algorithm for the extrapolation of the fouling layer thickness towards long intervals which are of practical importance. Moreover the momentum exchange between the continuous and dispersed phase will be investigated in order to estimate the modulation of local turbulence for different particle mass loadings. Parallel measurements will be carried out to resolve and determine the temporal and spatial three-dimensional fouling surface coverage. The thermal, mass and area based fouling resistance have to be assembled to a consistent figure of the total fouling state.As a fundamental result, a deep insight into the physical performance of dimpled surfaces considering particulate fouling will be obtained. Furthermore, quantities/operating numbers will be identified and qualified which allows the characterization of the thermal and fluid dynamic behavior of dimpled surfaces. The acquired insights are aimed to fill up the existing lack of knowledge and will provide additional quantities for the determination of the thermo-hydraulic performance in dependence of particulate fouling.

污垢，即在换热和/或传质表面形成沉积物是能源和化工过程设计和操作中的一个基本问题。由此造成的经济和生态破坏是巨大的。颗粒污垢，即悬浮颗粒在载体流体中的沉积，如沙或泥(见VDI WA 2006)，与结晶污垢一起是污垢问题的主要来源。结构换热器表面，如肋片、翅片或凹陷，通常用来提高换热速率，同时将额外的摩擦损失保持在最小。与其他涡流发生器相比，交错凹坑在能效方面显示出最好的可能解决方案，因为热释放的增加大约等于摩擦阻力的增加。尽管对污垢的重要性和运行过程中产生的问题有所了解，但在设计过程中，最大化传热和最小化水力损失仍是前沿性的。在前期研究项目《颗粒污垢对结构换热表面的影响》中，利用空间和时间高分辨率欧拉-拉格朗日大涡模拟和详细的实验研究，可以系统地分析颗粒污垢对凹陷表面的影响，在后续的研究项目中，旨在通过颗粒间碰撞和壁面粗糙度的影响来扩展所开发的数值方法。基于模拟的局部沉积颗粒分布和短污垢区间的污垢积分厚度，提出了一种新的具有实际意义的多尺度污垢层厚度向长区间外推的算法。此外，还将研究连续相和弥散相之间的动量交换，以估计不同颗粒质量负载下局部湍流的调制。将进行平行测量，以解决和确定时间和空间三维污垢表面覆盖率。基于热、质量和面积的污垢阻力必须组合成一个一致的总污垢状态的数字。作为一个基本的结果，将获得对考虑颗粒污垢的凹陷表面的物理性能的深入了解。此外，数量/操作编号将被识别和鉴定，这允许表征凹陷表面的热和流体动力学行为。所获得的见解旨在填补现有知识的不足，并将为确定依赖于颗粒污垢的热工水力性能提供额外的数量。

项目成果

期刊论文数量（5）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Flow structures and heat transfer over a single dimple using hybrid URANS-LES methods

DOI：
10.1016/j.compfluid.2018.01.014
发表时间：
2018-08
期刊：
Computers & Fluids
影响因子：
2.8
作者：
J. Turnow;R. Kasper;N. Kornev
通讯作者：
J. Turnow;R. Kasper;N. Kornev

Experimental and numerical approach to resolve particle deposition on dimpled heat transfer surfaces locally and temporally

DOI：
10.1016/j.ces.2020.115840
发表时间：
2020-12
期刊：
Chemical Engineering Science
影响因子：
4.7
作者：
Hannes Deponte;R. Kasper;S. Schulte;W. Augustin;J. Turnow;N. Kornev;S. Scholl
通讯作者：
Hannes Deponte;R. Kasper;S. Schulte;W. Augustin;J. Turnow;N. Kornev;S. Scholl

Multiphase Eulerian–Lagrangian LES of particulate fouling on structured heat transfer surfaces