The teaching of the traditional mold courses focus on the illustration of theoretical knowledge. Therefore, associating the design, evaluation, and manufacture links as a whole is difficult. Students cannot shape system knowledge, thereby making the study difficult. In addition, traditional teaching cannot meet the current enterprise needs of talents who have mold CAD/CAE/CAM technology. This study presents a teaching method that applies CAD/CAE/CAM technology to mold teaching. First, the positive effects of these technologies on the mold design and manufacturing process are introduced. Thereafter, lamp cover is used as an example to establish a series of computer-aided teaching development processes using existing software for mold design, mold flow analysis, and machining simulation. Lastly, survey results demonstrate that the effects of the proposed teaching method are better than the traditional method. Moreover, students and enterprises are substantially recognized in this teaching method.

Mechanical design course covers various contents, and most of them are complex theoretical knowledge. However, current teaching modes in China mainly combine textbook with PPT (PowerPoint) created in advance. This monotonous mode cause students to lose interests in their curriculum, and knowledge becomes difficult to gain. To improve teaching effectiveness, we propose a novel teaching mode by applying simulation technology to a particular mechanical design course. Using the chapter of gear transmission as an example, we also introduce a specific approach. Comparing traditional modes with the proposed mode, we demonstrate that combining simulation analysis technology with the content of mechanical design course can enrich the teaching process and improve students’ learning interests. The proposed approach can also help students analyze and solve problems with relevant knowledge and enhance their practical abilities. Thus, these students can satisfy the requirements of modern society for mechanical engineering graduates.

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In order to solve the problem of energy crisis and take the road of sustainable development, the development of renewable energy and recycling of low-grade waste heat have attracted more and more attention. As a new type of volumetric energy conversion device, scroll expander is wi dely used in Organic Rankine Cycle (ORC) waste heat recovery, because of its advantages such as small size and so on. Scroll profile is one of the main factors affecting scroll expander performance. Compared with the traditional constant section scroll profile with same suction volume, volume ratio and shell size, the new type of variable section scroll profile could reduce scroll tooth height, better mechanical properties and improve efficiency, therefore making it more suitable for working under complex operating conditions. In order to reduce the head invasion rate, airflow friction factor, the power loss at the air inlet, and improve the pneumatic power conversion efficiency, a new head correction method is proposed. Although R123, R134 and R245 are the most commonly used working medium in scroll fluid machinery, the selection of working medium in scroll expander is still a key problem. The overall performance of the scroll expander can be improved by designing different inlet shapes and positions or double-symmetrical exhaust ports. The radial leakage caused by axial clearance of scroll expander can be improved by developing new scroll profile to reduce the length of radial leakage line and optimizing the design of scroll top sealing mechanism. The tangential leakage caused by radial clearance can be improved by enhancing the manufacturing precision and installation accuracy of scroll plate and designing the radial variable mechanism. At present, fewer research has been carried out on the leakage of scroll expander. Therefore reducing the leakage loss to improve the performance of scroll expander is of great significance in the future research.

With the development of society, the energy crisis has become increasingly prominent, which greatly affects the sustainable development of the economy of various countries. Industrial energy consumption accounts for more than 70% of China’s total energy consumption, of which more than 50% is converted to industrial waste heat, and recyclable waste heat resources account for about 60% of the total waste heat resources, while China’s current utilization rate of industrial waste heat only reaches about 30%. The development of renewable energy and recovery of low-grade waste heat in industry is the key to solve the problem. As a type of volumetric expander with full flow expansion, the screw expander is extensively applied in the industrial waste heat recovery and geothermal energy generation industry because of its effective utilization of low enthalpy energy. Improving the performance of the screw expander as the core, the paper concludes and summarizes the research status of the leakage, rotor geometry, sealing and lubrication, processing and manufacturing, which can affect the performance of the screw expander. In addition, it also introduces the application status and potential utilization of screw expander.