SGER: Exploring New Hybrid Polymer-Nanofluids with Enhanced Flow and Heat Transfer Characteristics

SGER：探索具有增强流动和传热特性的新型混合聚合物纳米流体M。Kostic，机械工程系，北方伊利诺伊大学一个探索性的工作，一个未经测试的和新的想法，联合收割机结合减阻，聚合物添加剂与纳米粒子，从而开发新的混合，减阻传热纳米流体，即金属和金属氧化物纳米尺度粒子在普通基础流体的稳定悬浮液，提出。我们的目标将是首次生产混合纳米流体，不仅具有现有纳米流体的传热增强效果，而且同样重要的是，具有改善的悬浮稳定性和降低的流动摩擦。由大分子聚合物添加剂引入的流体结构的复杂性以及与不同基础流体中的纳米颗粒的不可预测的相互作用，应该为定制具有所需和增强特性的新混合流体带来许多有待探索的挑战和可能不可预见的机会。在基础流体中使用不同纳米颗粒的初始研究已经证明了比基础流体或具有相同类型但尺寸更大的颗粒的相当体积分数的基础流体高得多的热导率。此外，使用所谓的一步直接气相沉积法的非常小的金属纳米颗粒的增加比使用两步混合法的较大的金属氧化物纳米颗粒高得多。然而，在阿贡国家实验室（ANL）开发的现有一步法，尽管是一个很好的概念，但具有关键的缺点，并且实际上阻碍了进一步的发展，因为迄今为止仅生产了非常有限数量的增强纳米流体。第一个目标将是通过将减阻聚合物添加剂与纳米颗粒相结合来开发减阻传热纳米流体。随后，这些新的聚合物纳米流体的热机械，宏观流动和传热性能将进行。智力优势：该提案的核心是将减阻聚合物与高导热性纳米流体相结合的新想法。 降低流动摩擦和高导热性流体的发展可能会彻底改变传热领域。这些研究的结果可用于优化流体特性及其在现有关键应用以及新兴和新型应用中的应用。更广泛的影响：这项探索性的研究可能为开发具有前所未有的应用潜力的具有聚合物添加剂（包括生物纳米流体）的多样化，复杂的纳米流体开辟道路，被称为POLY-nanofluids。自然界充满了纳米流体，如血液，一种复杂的生物纳米流体，不同的纳米颗粒（分子水平）实现不同的功能。通过在实验室和自然界中研究（和理解）纳米流体，使用新的和可用的实验技术，以及通过开发这些流体和相关现象的基于计算机的模型，可以开发用于具有增强性质的纳米流体的定制设计的新方法和工具。这一探索性研究还将导致未来的项目，其中宏观尺度的测量将与纳米尺度的结构和动态测量相结合，使用激光和小角度X射线和中子散射技术。可能的应用包括在新的和关键的应用中更有效的冷却和加热，环境控制和清洁，生物医学应用以及纳米结构的定向自组装。

SGER: Exploring New Hybrid Polymer-Nanofluids with Enhanced Flow and Heat Transfer Characteristics M. Kostic, Department of Mechanical Engineering, Northern Illinois UniversityAn exploratory work on an untested and novel idea to combine drag-reducing, polymer additives with nanoparticles, and thus develop new-hybrid, drag-reducing heat-transfer nanofluids, namely, stable suspensions of metal and metal-oxide nano-scale particles in common base fluids, is proposed. The goal will be to produce, for the first time, hybrid nanofluids that not only have the observed heat transfer enhancement of existing nanofluids, but equally importantly, have improved suspension stability and reduced flow friction. Complexities in fluid structure introduced by macromolecular polymer additives and unpredicted interactions with nanoparticles in different base fluids, should open up a lot of challenges to be explored and possibly unforeseen opportunities for tailoring new hybrid fluids with desired and enhanced characteristics. Initial studies using different nanoparticles in base fluids have demonstrated much higher thermal conductivity than in the base fluids or with comparable volume fractions of the same type but larger size particles. Furthermore, the increase was much higher with very-small metal nanoparticles using the so called one-step, direct vapor-deposition method, than with larger metal-oxide nanoparticles using the two-step mixing method. However, the existing one-step method developed in Argonne National Laboratory (ANL), although an excellent concept, has critical shortcomings, and is virtually stalling further development since only very limited quantities of enhanced nanofluids have been produced so far. The first objective will be to develop drag-reducing heat-transfer nanofluids by combining drag-reducing, polymer additives with nanoparticles. Subsequently, thermo-mechanical, macroscopic flow and heat transfer properties of these new polymer-nanofluids will be undertaken. Intellectual Merit: The core of this proposal is the novel idea of combining drag-reducing polymers with high thermal conductivity nanofluids. The development of reduced flow friction and high thermal conductivity fluids may revolutionize the field of heat transfer. The results of such studies could be used to optimize fluid properties and their use for existing critical applications as well as emerging and novel applications. Broader Impact: This exploratory research may open the road for development of diverse, complex nanofluids with polymer additives (including biological nanofluids), dubbed POLY-nanofluids, with unprecedented application potential. Nature is full of nanofluids, like blood, a complex biological nanofluid where different nanoparticles (at molecular level) accomplish different functions. By studying (and understanding) nanofluids in the lab and nature, using new and available experimental techniques, and by developing computer based models of these fluids and related phenomena, new methods and tools for custom-design of nanofluids with enhanced properties may be developed. This exploratory research should also lead to future projects where macro-scale measurements will be combined with nano-scale measurements of structure and dynamics using laser light and small angle x-ray and neutron scattering techniques. Possible applications include more efficient cooling and heating in new and critical applications, environmental control and cleanup, bio-medical applications, and directed self-assembly of nanostructures.