Papers by Author: Kun Lv

Abstract: To make a six-bar mechanism of shaper to be more reasonable, at first, the geometrical models of a couple of mechanisms were created by the ADAMS and the kinematical analysis on the models was carried out. The simulation results reveal the regulation that the displacement, velocity and acceleration of plough head of shaper vary with time. Through comparing the movement charts, we can not only gain the performance parameters of the mechanisms, but also evaluate more comprehensively the performance of a shaper. Then through parameterized modeling, how the length change of each rod of the mechanism to affect its performance was analyzed. Taking the minimization of mechanism maximum pressure angle and acceleration as the objective function, the optimal design of mechanism was implemented. This method to use ADAMS to conduct simulation and optimization greatly improves research efficiency and shortens product development cycle.

Abstract: At first, mathematical movement model of six-bar mechanism of shaper was established with the vector analytic method. Then the geometrical model of six-bar mechanism of shaper was created by the simulation software ADAMS and kinematics simulation analysis on the model was carried out. The simulation results reveal the movement regularity and state information of plough head. By comparing the simulation results with theoretical calculation, the validity of this model and its simulation results were verified. Finally, through the parameterized modeling, how the length change of each rod of the mechanism to affect its performance was analyzed. Taking the plough heads working stroke as optimization objective, the optimal design of mechanism was realized. This method to use ADAMS to conduct simulation and optimization, on the one hand, greatly improves the research efficiency and shortens product development cycle, on the other hand, provides a theoretical reference for the actual mechanism design.

Abstract: Piezoelectric actuator was widely used in precision machinery as driving element used for their small size, high frequency, large resolution displacement and so on. A new micro-displacement amplifier driven by PZT is designed in this paper. The concrete machine parameters are studied out by finite element analysis. And the prototype is trial-manufactured. Experiential results show that the new mechanism has good displacement amplification performance and dynamic characteristics.

Abstract: By numerical simulation computation, after passing the pulsating flow, enhanced heat transfer mechanism in spirally fluted tubes was researched. Numerical result shows that pulsating flow can cause the outlet pressure to fluctuate cyclical and the extent of fluctuation increases with the pulsating flow frequency. The pulse flowing can make the fluid generate the whirlpool nearby the spirally fluted tubes and the phenomenon of periodic production, drift, and fall-off appears. Because of the vortex, the fluid motion and relative motion are enhanced. The pulse flowing can improve the coordination level between velocity and temperature, thus has strengthened the heat transfer effect.

Abstract: The process of Collaborative Product Development (CPD) comprises highly creative and knowledge-intensive tasks that involve extensive information exchange and communication among distributed teams. Traditional information management systems fail to provide adequate capability to support CPD, due to their inflexible data structures and hard-wired usage procedures, as well as their restricted ability to integrate process and product information. An ontology-based method of knowledge management is proposed to support CPD. The key idea hiding in the method is a flexible ontology-based schema with formally defined semantics that enables the capture and reuse of design knowledge. A part of CPD-oriented ontology library represented by UML is displayed.

Abstract: Product development is a concurrent process, which tends to be of such features as collaborative, distributed (web-based), interactive, and knowledge-intensive. Because the participants to work on a project come from different backgrounds, they will difficult to interact and understand one another. Ontology is a common language to model domain knowledge and makes the communication between people and the interoperability between systems easier. In this paper a CPD-ontology is built in IDEF5 to capture the knowledge about collaborative product development (CPD), then to serve as a foundation of knowledge management in the process of CPD.