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A numerical simulation for heat exchanger with continuous helical baffles was carried out. The study focuses on the effects of helix angle on heat transfer characteristics. The results show that both the shell-side heat transfer coefficient and pressure drop decrease with the increase of the helix angle at certain mass flow rate. The latter decreases more quickly than the former. The tangential velocity distribution on shell-side cross section is more uniform with continuous helical baffles than with segmental baffles. The axial velocity at certain radial position decreases as the helix angle increases in the inner region near the central dummy tube, whereas it increases as the helix angle increases in the outer region near the shell. The heat exchange quantity distribution in tubes at different radial positions is more uniform at larger helix angel.

Due to the complex structure of nuclear facilities in a high irradiation environment, people were hard to approach it, In view of these situation a fault diagnosis method based on HMM(Hidden Markov Model) of capturing the audio signal while facilities were operating was proposed. With the strong modeling ability, HMM could be applied to analyzing such as audio signal non-stationary time signal. By using this method, the original mechanical structures of nuclear facilities were not destroyed. The preposed sensors were needed as few as possible by the whole diagnosis system and which had a simple structure, low cost structure, the fault diagnosis rate was high and so on. State monitoring and fault diagnosis system of complex nuclear ower equipment could timely and effective to provide running status and potential failure information for operating personnel, which had a vital significance for the safe and reliable operation of nuclear power equipment.

China is a big agricultural country, which had many kinds of biomass resources. Biomass energy belongs to clean energy, it was available to achieve zero co2 emissions and substitute fossil fuels such as coal, oil and gas to be an important energy. Through the transformation of 35t/h coal-fired CFB boiler, which based on material and circulated carrier, burning biological energy, changed boiler from consuming one-time energy to the regenerative energy, which saved coal and prevented waste from directly emitting into the atmosphere to pollute the environment. It would save energy and increase the local farmers additional income by sell stem, which followed the trend of the national development strategy. The test data show that: this transformation of boiler is very successful, indicate that we can transform some original polluted boiler which consume coal to some degree and provide some experimental methods for these transformations.

In our country, the training target and cultivation mode of mechanical engineering in universities seems to akin to each other. Besides that, undergraduate students have their own limitations in knowledge, cognitive performance and thinking model. Aiming at that fact, we have set up “an educational mode of multi-level cooperation to personalized cultivate mechanical engineers’ innovation quality” and implemented that effectively through a long time of research and exploration. Furthermore, we have gradually formed a comparative impeccable personalized educational mode in the aspects of training target, talents training scheme, course system, educational mode, teaching evaluation and then constructed a smooth personalized cultivation and management mechanism, personalized training level and teaching contents focusing on the whole progress of education, flexible teaching method and advanced teaching means, a high quality teaching team with composite construction, showing a unique individualized teaching style and personalized teaching quality. We have achieved obvious teaching benefits, educational benefits and social benefits on comprehensively prompting quality-oriented education, especially on the cultivation of ability of innovating, learning and practicing. All these efforts to improve the cultivation quality of innovative talents major in mechanical engineering at universities have been widely recognized by our society.

In order to enhance the reliability of the automatic door operation, S7-200 programmable logic controller (PLC) was used as the core of the automatic door system. The principle of control system was analyzed with description of the control system hardware. It was introduced that the working process of control circuits about human body detection sensor and automatic door position detection and obstacle detection and so on. It was introduced how to choose a PLC type, to really settle the I/O orders. Combining the operation characteristics of programmable controller, a reasonable optimization was made for the work flow of the system. On this basis, using structured programming method, the program flow charts of main program module was developed. The debugging of the control system was developed on simulation software. The practical application shows that the control system was good and reliable.

With the development of the nuclear power and the requirement of the nuclear power equipments’ automation, the fault diagnosis system needs to vibration, noise, temperature and other signals generated by the sensor acquisition system under test. Monitoring technology in high radiation environment is very different from traditional monitoring technology, there is a high radiation resistant performance to sensors, amplifying circuit and transmission cable. The project group preliminary study results show that using sound detection method for real-time video monitoring to get more equipment operating information. According to the research in radiation effect of semiconductor devices and comparison experiment, radiation resistant performance of moving-coil acoustic sensor is above CMOS image sensor several orders of magnitude. This provides a powerful hardware support to it that fault diagnosis method based on capturing the audio signal while the nuclear facilities are operating is proposed.

The automatic and intellectualized reconstruction is the important way to improve and expand the traditional instrumental function. The surface roughness is an important indicator of effecting parts and products performance. On the basis of using precision measurement technology, electronic technology and computer technology synthetically, the principle and method of the automatic and intellectualized reconstruction of JB-3C Type Surface Roughness Measuring Instrument is mainly introduced, which is to reconstruct the hardware circuit and develop function in view of the flaws that the data processing speed of the traditional instruments is slow and they can not print the curve very abundant and even that operating steps are complicated and other shortcomings. And we adopt Matlab and VC++ mix programming to gather, process, demonstrate, analyze and compute data, which has high applicability and performance price ratio.

According to the requirements of dynamic design for high-speed and heavy-loading marine gear, in view of slotting processing advantages, modification profile slotting cutter used to achieve modify high-speed and heavy-loading marine gear, and the modification profile of slotting cutter designed to the profile which consists of multiple segments of different profile shape profile angle, the modification profile angles of slotting cutter corresponding sections of involutes deduced using the profile angle error analysis theory, modification profile of slotting cutter precision designed based on engagement principle of slotting gear.

Slotting process used to achieve modify heavy-loading mine gear.According to the pitch circle radius of gear tooth profile modification is difficult to accurately draw, reverse-designed the profile of the modification slotting cutter fold may occur on the cusp, generating simulation for slotting profile modification is implemented using MATLAB based on engagement theory of slotting process,which can test whether the pitch circle is set to reasonable, to avoid resulting the top or root of conjugate gear’s profiles be cut,achieved the adaptive design of profile modification slotting cutter.