Papers by Author: Ying Ning Hu

Abstract: Sawing concrete with diamond saw blade is a complex process with alternating loading. However, due to the poor working conditions of the thin circular blade made of high manganese steel core, and the lack of research on its failure mechanism, a large number of used blade are abandoned every year in China and all over the world without steel core reused. Therefore, exploring the failure mechanism of diamond saw blade can improve the cutting quality and efficiency, and extend the service life of the saw blade. In this paper, the failure mechanism of diamond saw blade sawing concrete was analyzed through segment wear experiment and microstructure observation of segments and steel core of failed sawblade. The results showed that the stress concentration exited at the bottom of slot, where it became the most dangerous section. The crack at the bottom of the cooling hole caused the saw blade to deviate violently and bear unevenly. The microstructure is great different along the outer to the center of the steel core. The closer to the teeth of the saw blade, the more obvious the microstructure change, while the central core still retains the original structure. Under the same sawing area of 0.01m², the stable dust adhesion of plain concrete is less than that of the steel fiber concrete. However, when the dust adhesion increases to more than the stable adhesion, the phenomenon of blockage will occur. Therefore, deflection, crack, wear and burn were the main failure reasons of diamond saw blade when sawing concrete.

Abstract: This paper focus on the study of Ceiling radiation assist with Ground source heat pump air conditioning system which to analysis the operation characteristic by experiment. By testing the ceiling, all round the room air temperature, air temperature, wall temperature and the floor temperature, research the fresh air temperature have influence on the indoor environment temperature and vertical temperature. At the same time, analyzes radiation plate heat transfer per unit area with the end of the air conditioning water temperature and flow relationship. Experiments show that when the room ceiling radiation + natural air to indoor vertical temperature gradient is the largest, the second is ceiling radiation + no fresh air, indoor vertical temperature gradient is the smallest ceiling radiation + preheat air condition, when the system is stable, 2 meters below the vertical temperature difference about 1°C.

Abstract: Experiments of diamond sawblade sawing plain concrete are conducted with different sawing parameters. Real time signals of sawing force, vibration, acoustic emission and noise are collected, and Multi-scale wavelet analysis is adopted to analyze the interrelationship and interrelation of real time signals. Supervision and distinction of processing can achieved after Multi-scale wavelet analysis.

Abstract: t is known that cutting force is the key to reasonably select cutting parameters, and the base to study the cutting mechanism. Genetic Algorithm and multiple regression analysis were adopted to achieve cutting force predicted model of multi-diamonds fast milling hard-brittle materials with defined diamond grains pattern by single diamond fast milling hard-brittle materials experiments. Results show that cutting force predicted model by genetic algorithm has higher precision than that model by multiple regression, and the cutting force prediction method based on genetic algorithm is more suitable for those hard-brittle materials which components are relatively soft and simple. Predicted model can afford another study direction for processing analysis of diamond tools, tools making and processing parameters selection from the view of diamond grain practice cutting.

Abstract: The paper is on research of the operating characteristic of the ground source heat pump air conditioning system that applied in large scale gymnasium in hot summer and warm winter zones, combining with operating characteristic of the real application of the GX autonomous region's gymnasium project. Utilizing the SPSS software aiding the Multivariate nonlinear Regression analysis, via MATLAB's optimization methods for optimizing and stimulating to obtain the most economic, practical and reliable mode and the optimal system parameter. The purpose of this research lies in making it available for the system to exert its best working condition and providing reference for real project design.

Abstract: Taking one multifunction building in Guangxi as example. The paper introduces the author team who independent design and imply a ground-source heat pump (GSHP) and cooling tower hot water and air-condition joint supply system (GCHAS) which application in a multifunction building in hot summer and warm winter zone. The system performance is analyzed through the experiment. And the result of experiment proves the superiority and economy of ground-source heat pump technique in multifunction building. The author also research how to realize the energy saving and comprehensive application of ground-source heat pump work in multifunction building.

Abstract: This paper dynamically simulates the soil source heat pump air conditioning system of a library in Nanning with the eQUEST software combined with the geology and climate characteristics, unit parameters. Comparing the simulated values with the measured values to verify the correctness of the model. Then simulate and analyze the variation of ground temperature rise at well bore with long-term intermittent operation for the system and the influence of different well spacingground and backfill materials thermal conductivitywell depth on the outlet temperature and the ground temperature rise at well bore. The simulation results show that the reasonable selection of relevant parameters has important significance to improve the operating performance and economy of the system.

Abstract: Diamond cup wheel is one of important tools for machining of ceramic tile. In this paper, ceramic tiles were ground by diamond cup wheels which segments adding nano-scale rare-earth oxide and nano-scale carbide on a special designed test machine. The wear resistance of diamond cup wheels and materials’ removal process of ceramic tiles had been tested, and grinding ratio were calculated and compared. Different grinding ratios can be obtained according to different technological parameters. The segments of adding nano-scale rare-earth oxide and nano-scale carbide were observed from microgram and metallography structural pattern. The results showed that nano-scale rare-earth oxide and nano-scale carbide can fine structure, make grain boundary clear and increase grasping of diamond grits.

Abstract: Annual cold heat adjustment is one of the key problems in the practical application of ground-source heat pump system. According to the energy-consuming characteristics of the building in hot summer and warm winter area zone and engineering practice, the author puts forward the multi-level heat shunt ground source heat pump systems(GSHPS). Reasonable system can be matched according to the characteristics of the cold water chiller and the water source heat pump, which takes full advantages of soil cold/heat source, improves the efficiency of the soil heat exchanger, and balances underground temperature field effectively.

Abstract: Taking one club as example, the application of the subtropical region ground source heat pump technology on indoor constant temperature swimming pool water heating load calculation and type selection of equipment is introduced. The system performance is analyzed through the experiment. The energy consumption cost of this technique is compared with electric boiler and oil-fired boiler, and the result shows ground source heat pump technique is superior and economic.