Papers by Author: Xi Liang Zhang

Abstract: For the current problem that grate bed can not recover its own waste heat in the course of cycle working, combined with the structure of the chain grate and hot air flow process, a three-section heat recovery unit of grate bed and waste heat recovery hot air flow process are designed. According to the principle of repeated convective heat transfer, the amount of recovering waste heat of heat recovery unit is estimated, and simulation analysis is conducted by using fluent software. The results show: after three heat exchange between the hot exhaust gas at around 100°C and the grate bed, the hot gas at a temperature of around 427 °C can be obtained, and the waste heat recovery rate is above 60%; simulation results are compared with the estimated value so that it can be obtained that the differences between the two values in the temperature of three-section outlet gas are basically consistent, about 8°C, 4°C, 7°C respectively, which verifies the effectiveness of the heat recovery unit design and the accuracy of Fluent simulation.

Abstract: With the socio-economic development and increasingly higher buildings, public concern is growing over high-rise fire evacuation issues. Considering the shortcomings of the existing escape device and methods, such as difficult speed adjustment, high demand for escaping skill, difficult unification of speediness and security, poor recycling etc, an integrated speed limited escape method is proposed by analyzing kinetics of high-rise evacuation. On one hand, the escape acceleration is limited by using centrifugal mechanism, on the other, according to the building height and people's weight, the landing speed of people is restricted by controlling the break height and braking force of brakes. The developed escape machine use the micro-controller to monitor the height and speed real-timely, control the brake automatically and start rope recycling mechanism after the landing, which achieves quick and safe escape. The experiment shows that when heavy object weighing around 75kg drops from a height of 14. 6m, the maximum speed reaches 3m/s, the landing speed is less than 0.5m/s and the falling time is within 7.5s, which achieves better escaping effect.

Abstract: To improve electrical operational flexibility in use and save energy, a universal multi-function digital remote control electronic switch for variety of household appliances is developed by adopting wireless sensor networks and infrared sensing technology. To NRF9E5 wireless microcontroller as the core, electronic switch that formed by the remote control and a number of switch nodes forms short-distance wireless communications network. Remote control is equipped with clock circuit, buttons and LCD display; switch node with infrared sensor, human body detection circuit, relay and control circuit. Switch can be controlled by remote control, human infrared sensor or setting time. The application shows that it greatly increases operational flexibility with easily integrating with various existing electrical switches and has obvious energy saving effect.

Abstract: Considering the greater character differences between matrix and soil, and the great disparity in physicochemical properties of various substrate, now there is no special equipment to test matrix moisture, electrical conductivity (EC) and salinity of medium .On the basis of analyzing physicochemical properties of various substrate, the relationship between output voltage and water content is studied through piezoelectric type soil moisture probe trial. With "voltage-current" four-terminal method, multi-parameter integrated sensor testing medium moisture and electrical conductivities developed, and through the solution calibration EC measuring model is established. Then relationships among matrix water content, electrical conductivity and salinity are analyzed, and salinity testing model is established. A portable low-cost in-situ multi-parameter detection apparatus, testing substrate humidity, EC and salinities, developed by adopting MCU SPCE06A. Experimental results indicate that detection accuracy of the equipment can meet the need of soilless culture production, and it has greater application and dissemination value.

Abstract: Considering the current problems of low temperature of recovered gas, the direct gas emission of the fourth cooling zone in the operation of the annular cooler, thermal airflow process for the annular cooler is improved by analyzing the thermal airflow process and the structure of the annular cooler and using the principle of repeated convective heat transfer. Thus the above-mentioned problem can be solved. Simulation model of its thermal airflow process is established and the simulation results, obtained by using Fluent software, are as follows: the temperature of the gas in the first cooling zone entering the rotary kiln of the improved is about 110°C higher than that of the unimproved, the temperature of the gas in the second cooling zone entering the preheat zone I of the chain grate of the improved is about 150°C higher than that of the unimproved, and the temperature of the gas in the fourth cooling zone entering the downdraft drying zone of the chain grate of the improved is about 50°C higher than that of the unimproved. Pellet heat recovery efficiency is increased significantly.

Abstract: For the low status of straw utilization, in order to improve the mass production rate and reduce energy consumption, according to the classification principle and the idea of “first cut ,second crush”, a set of cutting, screening, crushing, and re-screening as one of the universal closed type straw cutting mill was designed. Design plan was set, the structure diagram of the process of cutting and screening was given, major working parts such as the feeding body, cutting body, shattered body were designed and calculated, the cutting and crushing productivities was 0.29t/h and 0.32t/h respectively, matching power was 10KW. It plays an important role on the richness variety of straw processing equipments, increase straw utilization, and reduction energy consumption.

Abstract: With the enhanced awareness of energy conservation and eye health, more and more concerns and attentions are focused on the teaching building lighting control technologies and related products. In order that the lighting management of teaching building can be facilitated and the lighting effects and lighting conditions of teaching can be improved, the lighting automatic control system for teaching building is designed by adopting Dimmable electronic ballasts and wireless sensor network. To achieve the control of light switch and regulation of light intensity, the infrared sensor is chosen to detect the human body and illumination sensor used to detect the illuminance values. System operation shows that the lighting control system is stable, reliable and flexible. Compared with the traditional lighting, it can generate 10%~15% energy savings in one classroom within a week by statistical estimation, which has confirmed that the lighting control system realizes significant energy savings.