Papers by Author: Hua Bo He

Abstract: With the particle transfer model and object-oriented programming method, the initiatory computer simulation software of indirect drying process is developed in windows XP system and MFC environment. The overall coefficient of heat transfer in the drying process and the changes of material humidity and temperature between the inlet and outlet are calculated by the simulation software. The actual test data verify that the computer simulation software is convenient, effective and reliable.

Abstract: By the combination of orthogonal experiments and moldflow simulation analysis, the warpage of a food tray is analyzed under the combined effects of multi-molding process parameters. By this method, it can gain the experiment data which can basically reflect the overall situation using fewer number of simulation analysis. In addition, the effects degree of different molding process parameters for warpage are researched, and the optimized parameter combination is obtained. It can avoid the one-sidedness of individual analysis of the various factors and solve the unreasonable appearance of process parameter settings. With the help of results, it can fasten the mold developing schedule, thus shorten the cycle of product development, and improve the quality of products and the competitive ability of enterprise.

Abstract: Bond graphs are a domain-independent graphical description of dynamic behavior of physical systems. It is particularly suited for the concurrent design of multidisciplinary systems (including mechanical, electrical, hydraulic or pneumatic components). In this paper, we present our work on the conceptual design representation using bond graphs methodology to support the early stage of product development, especially the conceptual design of mechatronic products. Following the introduction of the fundamental concepts, a advanced notion so called activation is given to present signal systems (e.g. feedback controlled systems). Finally, a controlled DC motor driven system example is used to illustrate the process of model building and analysis of interdisciplinary systems based on bond graphs.

Abstract: Injection moulding is an important manufacturing method for plastic parts. There are however many moulding quality defects caused by inappropriate setting of moulding process conditions, as well as the poorly designed plastic part geometry. Often, stiffeners are used in a plastic part to increase its strength. However, if the stiffeners are not designed properly, they will introduce one or more moulding quality problems, which in turn will worsen the part strength rather than increasing it. Although there have been quite a lot of researches on optimising moulding quality, it is often difficult to minimize multiple quality defects simultaneously. In this paper, we propose to employ flow uniformity as the optimisation objective to address this problem. A number of stiffener layout designs are evaluated in terms of this objective to determine the best design, where standard deviations of filling times and pressures at the extremities of the plastic part are used to measure the uniformity of flow. A simple case study is also presented to demonstrate the applicability of the proposed methodology.

Abstract: By the combination of orthogonal experiments and moldflow simulation analysis, the warpage of a thin-wall injection molded parts is analyzed under the combined effects of multi-molding process parameters. By this method, it can gain the experiment data which can basically reflect the overall situation using fewer number of simulation analysis. In addition, the effects degree of different molding process parameters for warpage are researched, and the optimized parameter combination is obtained. It can avoid the one-sidedness of individual analysis of the various factors and solve the unreasonable appearance of process parameter settings. With the help of results, it can fasten the mold developing schedule, thus shorten the cycle of product development, and improve the quality of products and the competitive ability of enterprise.

Abstract: Behavioral characteristic is one of the important targets in conceptual design and re-design of electromechanical products. To summarize the knowledge of behavior characteristics of electromechanical products, this paper proposed the concepts of behavioral effect, elemental behavior and behavioral chain. It made the modification to classical Petri nets, then analyzed and expressed the behavior characteristics using the modified Petri nets. Finally, a case study of an electric nail-gun was conducted to demonstrate the feasibility of the proposed methodologies.

Abstract: In conceptual mechanical design process, designers sometimes focus their attentions on mapping a sub-function or functional unit to a single mechanism or system, and ignore the interfaces among the structural elements. This paper first summarized the behavioral characteristic of the interfaces in energy, mechanics, kinematics by analyzing the roles, classification and connection styles of such interfaces. Subsequently, it introduced the concepts of function and free surface, and gave the interface design process. Finally, a case study was conducted to demonstrate the feasibility of the proposed methodologies.