Gas Expanded Lubricants: Smart Fluids for Improving Efficiency of Wind Turbines

这项研究的目标是开发提供气体膨胀润滑剂（gel）所需的基础知识基础，以提高下一代风力涡轮机齿轮和轴承的效率。凝胶是合成润滑剂和溶解液体二氧化碳在中等压力下的二元混合物。这些润滑流体的特性可以通过控制混合成分来动态调整，因此可以帮助减少受动态变化负载影响的风力涡轮机的低效率运行。可靠的和自适应的润滑油系统是必要的，以使涡轮机更大，或安装在难以接近或海上站点。所提议的研究将建立化学理解的基础，这对于选择最佳性能和最小环境影响所需的适当组件和工艺操作条件是必要的。初步的建模结果表明，凝胶可以将流体膜轴承的功率损失降低20%以上。本研究将在相关条件下测量凝胶的力学和热特性，并在改进的转子试验台上评估其性能。本研究分为5个任务：1)研究润滑油和二氧化碳的高压相行为；2)测量凝胶在相应压力和温度条件下的流变性；3)评价凝胶相对于直系润滑剂的热特性；4)开发了一个使用凝胶测量轴承性能的实验测试平台；5)建立凝胶输送生命周期模型，建立大规模可行性。这项研究具有潜在的变革性，因为它代表了一种全新的风力涡轮机润滑方法，在提高风能发电的能源效率方面有很大的希望。提出的研究有可能促进对高压液/气混合物的摩擦学、相行为和流动特性的基本理解。具体而言，该研究计划旨在揭示两个重要的润滑剂参数，粘度和密度，在预测旋转机械的刚度和剪切力方面的影响。这些关系的理解将发展为一个家族的生物基合成润滑油化学。研究结果将在模拟真实风力涡轮机典型非线性载荷的特殊改装试验台上进行实验验证。这种新的认识将总结为一套设计指南和工具，可以很容易地被风能行业使用。这项工作的结果将对试图提高涡轮机寿命和降低风力发电成本的风力涡轮机制造商和支持行业产生明确的影响。更广泛的影响教育活动将有助于在弗吉尼亚州发展绿色能源教育项目的更大努力。最近与风能等可持续技术相关的制造业和服务业的蓬勃发展表明，必须实施培训计划，为希望在这些领域工作的人提供技能。ppi与西南弗吉尼亚高等教育中心合作，提供风力涡轮机基础知识和维护课程，以增加大学和社区学院学生的现有课程。研究成果将通过弗吉尼亚大学（UVa）的旋转机械与控制（ROMAC）校企合作项目及其40个工业合作伙伴（包括通用电气、劳斯莱斯能源和普莱克斯）转移到工业领域。

0967915ClarensThe goal of this research is to develop the fundamental knowledge base needed to deliver gas-expanded lubricants (GELs) for improved efficiency in gears and bearings of next-generation wind turbines. GELs are binary mixtures of synthetic lubricants and dissolved liquid carbon dioxide maintained at moderate pressure. The properties of these lubricating fluids can be dynamically adjusted by controlling mixture composition, and consequently can help reduce operating inefficiencies for wind turbines that are subject to dynamically changing loads. Reliable and adaptive lubricant systems are necessary for turbines to be made larger or to be installed in inaccessible or offshore sites. The proposed research proposed will build the foundation of chemical understanding that is necessary to select proper components and process operating conditions needed for optimal performance and minimum environmental impact. Preliminary modeling results suggest that GELs could reduce power losses in a fluid film bearing by over 20%. Intellectual MeritThis study will measure the mechanical and thermal characteristics of GELs under relevant conditions and evaluate their behavior in a modified rotor test bed. The proposed study is broken down into five tasks: 1) Study the high pressure phase behavior of lubricants and carbon dioxide; 2) Measure the rheology of GELs under relevant pressure and temperature conditions; 3) Evaluate the thermal characteristics of GELs relative to straight lubricants; 4) Develop an experimental testbed to measure bearing performance using GELs; 5) Create a life cycle model of GEL delivery to establish large-scale feasibility. This research is potentially transformative because it represents a completely new approach to wind turbine lubrication that has considerable promise to make significant improvements in increasing the energy efficiency for electric power generation from wind energy. The proposed research has the potential to advance fundamental understanding of the tribology of high-pressure liquid/gas mixtures, their phase behavior, and flow properties. Specifically, the research plan seeks to reveal the effect of two important lubricant parameters, viscosity and density, in predicting stiffness and shear forces in rotating machinery. An understanding of these relationships will be developed for a family of bio-based synthetic lubricant chemistries. The results will be validated experimentally using a specially modified test rig that mimics the nonlinear loadings typical of real wind turbines. This new understanding will be summarized in a set of design guidelines and tools which can be easily used by the wind industry. The results of this work will have clear implications for wind turbine manufacturers and supporting industries trying to improve turbine life and reduce the generation cost of wind electricity.Broader ImpactsThe education activities will contribute to a larger effort to develop a green energy education programs in the state of Virginia. The recent boom in manufacturing and service sectors associated with sustainable technologies such as wind energy suggests that training programs must be implemented to provide skills for people hoping to work in these areas. The PIs have partnered with Southwest Virginia Higher Education Center to provide a course in wind turbine fundamentals and maintenance to augment existing curricula for both university and community college students.Research outcomes will be transferred to industry via the Rotating Machinery and Controls (ROMAC) university-industry cooperative program at the University of Virginia (UVa) and its forty industrial partners, including GE, Rolls Royce Energy, and Praxair.