Papers by Keyword: Physical Mechanism

Abstract: Hybrid material systems are designed by the specific combination of different materials. As a result, expanded property profiles can be achieved, which would not be possible with monolithic material solutions. For lightweight, high strength and high rigidity, complex shaped structural components, which are used in the automotive industry and in aerospace, hybrid material systems offer an outstanding potential. A comprehensive understanding regarding the interaction of the individual components of the hybrid material is of great importance for a more efficient design of future structures. In this work, existing hybrid solutions for industrial applications and those, which are subject of current research, are analyzed and categorized first. Intrinsic and extrinsic material combinations are considered at different levels, ranging from hybrid laminates on shell level to complex hybrid structures on component level. Based on the situation analysis, different hybrid solutions are evaluated and compared considering the requirements of the automotive industry. Furthermore, the associated physical mechanisms which are responsible for the respective property profile are considered and explained systematically. The long-term objective of the work is to establish a methodology to derive the necessary physical mechanisms and, based on that, to derive optimal hybrid solutions for desired property profiles.

Abstract: Culture is an important factor for sustainable development of the enterprise, paid wide attention by the academic and corporate, at the same time, there are also many for enterprise culture research, which is mainly aimed at a particular analysis of the enterprise culture construction. With the development of society and the development, the social reform and innovation are going on unceasingly, Enterprise culture as enterprise adapt to the society and the demand of people also need unceasingly innovation and development, and cultural innovation and the cultural development is complementary relationship. Namely, cultural innovation is the foundation of the development of culture and cultural innovation promotes the cultural development, and cultural development and cultural innovation, make the cycle is progress. This paper is mainly based on cultural development and cultural innovation mechanism analysis, from mechanical angles of the culture construction and cultural innovation development of the coupling model, and through empirical analysis more strongly proves its of the coupling relationship between each other, to lead the enterprise cultural innovation and development.

Abstract: Wind loads encountered by wind turbine systems exhibit obvious randomness. Conventional researches of wind loads mainly target developing power spectrum density models or correlation functions. However, it is extremely difficult to deal with several key problems of stochastic dynamics of wind turbine systems in such a frame due to the absence of physical mechanisms. In this paper, the physical tradition in the study of stochastic dynamics is followed to investigate wind loads of wind turbine systems. Along the physical tradition, the physics-based modeling is primarily put forward. Based on the random function description of stochastic processes, a new concept of random Fourier function is proposed to establish two physical wind spectrum models of wind turbine systems. One of them is the random Fourier spectrum model which determines wind loads on wind turbine towers, the other is the rotational Fourier spectrum model which decides wind loads on rotating blades. As the two physical wind spectrum models can effectively prevent the essential drawbacks of the phenomenological ones, they are suggested to be adopted in the wind-induced dynamic reliability evaluation of wind turbine systems.

Abstract: Metal rubber material is a new type of elastic and porous material which develops from metal materials. The macro-structure of metal rubber is reticular just as high polymer, made up of fine metal wires. In this paper, the testing equipment which can test micro-motion of metal rubber is designed and the compressive force-displacement curve along molding of metal rubber has gain. The cure along molding of metal rubber has three different characteristic stages. In different characteristic stages, the deformation of metal rubber material has different micro physical mechanism. The micro physical mechanism of different deformation periods is summarized by the micro analyses of three different characteristic curve stages and the study of metal rubber molding technology. Based on the manufacture technology and molding process, the spring wires in metal rubber material have contacted adequately after molding. The micro physical mechanism of metal rubber material in this stage is produced by blank tear combination deformation in linear elastic of spring wires. Because of the deformation stage is very little; the stiffness of metal rubber material is represented linear characteristic in this stage. The contacted points of spring wires are slide along with deformation increasing. The stiffness of metal rubber material is reduced after early linear deformation stage. The compressive force-displacement curve represents soft characteristic stage in macro- expression. When the most contacted points of spring wires are slide along with deformation increasing, the stiffness of metal rubber material is rapid rise. The exponential reinforcement stage is caused by the strongly constraints among spring wires. The micro physical mechanism can explain the different characteristic stages of metal rubber material on compressive performance.

Abstract: Understanding the dynamic behavior of concrete in rapid loading is an issue of great importance in civil engineering. In this study, an experimental program was performed to investigate the dynamic behavior of concrete subjected to different strain-rate loadings. From the test results the rate-dependent effect on the ultimate strength of concrete was confirmed, i.e., the strength increases with the increasing strain rate. The dynamic failure process of concrete in tension and physical mechanism were discussed based on the experimental observations.