The lubricating characteristics of CVTF(continuously variable transmission fluid) mixed with a multi-functional complex additive were studied. The said complex additive contained an organic borate ester and a new type...The lubricating characteristics of CVTF(continuously variable transmission fluid) mixed with a multi-functional complex additive were studied. The said complex additive contained an organic borate ester and a new type of friction improver comprising phosphorus element and poly-methylmethacrylate(PMMA), and a viscosity index improver. The viscosity-pressure characteristics were evaluated by a high-pressure quartz viscometer, and the anti-wear property was investigated by a four-ball friction tester. The mechanism of lubrication by the CVTF was studied using X-ray photoelectron spectroscopy(XPS). The results showed that CVTF T10, which contained a multi-functional complex additive, exhibited excellent properties, featuring greater solidification pressure and pressure-viscosity coefficient, improved oil film strength, and low wear value. These attributes meet the special CVTF requirements for "high friction and low wear" that make it possible to provide both traction and lubrication. The lubricating mechanism was varied using different functional elements, such as inert and active elements. Sulfur and phosphorus are active extreme pressure elements that can react on the metal friction surface and produce an extreme pressure lubrication film. Boron is an inert functional element and does not react upon the metal surface; boron is only adsorbed onto the metal surface to act as a lubricant for adsorption film and fillers.展开更多
In order to provide a guidance to specify the element size dynamically during adaptive finite element mesh generation, adaptive criteria are firstly defined according to the relationships between the geometrical featu...In order to provide a guidance to specify the element size dynamically during adaptive finite element mesh generation, adaptive criteria are firstly defined according to the relationships between the geometrical features and the elements of 3D solid. Various modes based on different datum geometrical elements, such as vertex, curve, surface, and so on, are then designed for generating local refined mesh. With the guidance of the defmed criteria, different modes are automatically selected to apply on the appropriate datum objects to program the element size in the local special areas. As a result, the control information of element size is successfully programmed covering the entire domain based on the geometrical features of 3D solid. A new algorithm based on Delatmay triangulation is then developed for generating 3D adaptive finite element mesh, in which the element size is dynamically specified to catch the geometrical features and suitable tetrahedron facets are selected to locate interior nodes continuously. As a result, adaptive mesh with good-quality elements is generated. Examples show that the proposed method can be successfully applied to adaptive finite element mesh automatic generation based on the geometrical features of 3D solid.展开更多
How to automatically generate three-dimensional finite element Delaunay mesh by a peifected node connection method is introduced, where nodes are generated based on existing elements, instead of independence of node c...How to automatically generate three-dimensional finite element Delaunay mesh by a peifected node connection method is introduced, where nodes are generated based on existing elements, instead of independence of node creation and elements generation in traditional node connection method. Therefore, Ihe the difficulty about how to automatically create nodes in the traditional method is overcome.展开更多
基金financially supported by the China National Machinery Industry Corporation Science & Technology Development Fund (SINOMACH12 No.180)
文摘The lubricating characteristics of CVTF(continuously variable transmission fluid) mixed with a multi-functional complex additive were studied. The said complex additive contained an organic borate ester and a new type of friction improver comprising phosphorus element and poly-methylmethacrylate(PMMA), and a viscosity index improver. The viscosity-pressure characteristics were evaluated by a high-pressure quartz viscometer, and the anti-wear property was investigated by a four-ball friction tester. The mechanism of lubrication by the CVTF was studied using X-ray photoelectron spectroscopy(XPS). The results showed that CVTF T10, which contained a multi-functional complex additive, exhibited excellent properties, featuring greater solidification pressure and pressure-viscosity coefficient, improved oil film strength, and low wear value. These attributes meet the special CVTF requirements for "high friction and low wear" that make it possible to provide both traction and lubrication. The lubricating mechanism was varied using different functional elements, such as inert and active elements. Sulfur and phosphorus are active extreme pressure elements that can react on the metal friction surface and produce an extreme pressure lubrication film. Boron is an inert functional element and does not react upon the metal surface; boron is only adsorbed onto the metal surface to act as a lubricant for adsorption film and fillers.
基金This project is supported by Provincial Project Foundation of Science and Technology of Guangdong, China(No.2002104040101).
文摘In order to provide a guidance to specify the element size dynamically during adaptive finite element mesh generation, adaptive criteria are firstly defined according to the relationships between the geometrical features and the elements of 3D solid. Various modes based on different datum geometrical elements, such as vertex, curve, surface, and so on, are then designed for generating local refined mesh. With the guidance of the defmed criteria, different modes are automatically selected to apply on the appropriate datum objects to program the element size in the local special areas. As a result, the control information of element size is successfully programmed covering the entire domain based on the geometrical features of 3D solid. A new algorithm based on Delatmay triangulation is then developed for generating 3D adaptive finite element mesh, in which the element size is dynamically specified to catch the geometrical features and suitable tetrahedron facets are selected to locate interior nodes continuously. As a result, adaptive mesh with good-quality elements is generated. Examples show that the proposed method can be successfully applied to adaptive finite element mesh automatic generation based on the geometrical features of 3D solid.
基金This project is supported by Provincial Natural Science foundation of Guangdong!(970516)
文摘How to automatically generate three-dimensional finite element Delaunay mesh by a peifected node connection method is introduced, where nodes are generated based on existing elements, instead of independence of node creation and elements generation in traditional node connection method. Therefore, Ihe the difficulty about how to automatically create nodes in the traditional method is overcome.
