摘要：
Thermal issues of lithium ion batteries are key factors affecting the safety, operational performance, life, and cost of the battery. An electrochemical–thermal coupling model based on thermoelectrochemical basic data was established to investigate the thermal behavior of LiFePO4 lithium ion battery. In this paper, the finite element method was used for simulation of temperature field distribution inside battery during charge–discharge process, and the influence of the charge–discharge rate and ambient temperature on the distribution of temperature field was summarized. The results showed that the highest temperature of battery was recorded at the junction of negative and separator during charge–discharge process. At a low discharge current, the modeling results agreed well with the experimental data. When the ambient temperature was 303.15 K, the maximum temperatures inside the battery were 304.60, 304.83, 306.55, and 309.96 K for 0.1, 0.2, 0.5, and 1.0 C charge–discharge rates, respectively. If the ambient temperature increased to 323.15 K, the maximum temperatures were increased by 24.96, 27.91, 33.18, and 32.59 K for 0.1, 0.2, 0.5, and 1.0 C charge–discharge rates, respectively, and the homogenous temperature field distribution inside the battery was worse.
作者机构：
[毛聪; 张健; 龙春光; 余小峰; 唐昆; 汤旺] Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, China;[彭平] College of Materials Science and Engineering, Hunan University, Changsha, China;[毛聪; 张健; 龙春光; 余小峰; 唐昆; 汤旺] Key Laboratory of Security Design and Reliability Technology for Engineering Vehicle, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, China
通讯机构：
Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, China
摘要：
In this paper, short basalt fiber-reinforced polyoxymethylene (POM) composites were prepared by melt blending and injection molding. The mechanical and tribological properties of the composites were studied by an orthogonal experiment. It was found that the optimal combination of fiber length 4 mm, fiber content 20 wt% and treated with KH550 would result in a comprehensive property which is 27.45% higher tensile strength, 9.65% higher impact strength and 18.11% higher flexural strength with compared to that of pure POM. But its tribological properties would be worse with the addition of the basalt fibers. After incorporating 10 wt% of polytetrafluoroethylene (PTFE) into the composites, the tribological properties of the composites was improved, closed to that of pure POM, with an insignificant decrease to their mechanical properties. Moreover, the morphology of fracture surfaces and worn surfaces evaluated by scanning electron microscopy showed good agreement with the results of the literature.
摘要：
Efficient application of minimum quantity lubrication (MQL) in grinding is not only related to grinding conditions and delivery parameters but also affected by spraying atomization characteristics. In this study, a double-outlet nozzle is proposed and the flow field of the MQL grinding is investigated by two-stage atomization model. The side-mixing structure of double-outlet nozzle indicates that the grinding fluid is atomized at the windward side and the flow rate of grinding fluid for a single radial hole is smaller than that for the liquid pipe. Therefore, more excellent atomization performances, in terms of liquid droplet size, uniformity, and velocity of the liquid droplets, are obtained for double-outlet nozzle in comparison with single-outlet nozzle. The liquid droplets sprayed from auxiliary outlet of double-outlet nozzle impact on the grinding wheel and change the airflow direction around the grinding wheel. Thus, the air barrier around the grinding wheel is disturbed and the liquid droplets sprayed from main outlet can be injected into the grinding zone easily. Experimental results indicate that two-stage atomization model is reliable.
作者机构：
[张健; 汤旺; 邵磊; 余小峰; 龙春光] College of Automobile and Mechanical Engineering, Changsha University of Science and Technology, Changsha;410114, China;Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, Education Department of Hunan Province, Changsha;[陈荐] Key Laboratory of Efficient and Clean Energy Utilization, Education Department of Hunan Province, Changsha;[张健; 余小峰; 龙春光] 410114, China<&wdkj&>Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, Education Department of Hunan Province, Changsha
通讯机构：
[Zhang, J.] C;College of Automobile and Mechanical Engineering, Changsha University of Science and Technology, Changsha, China
摘要：
The transient thermo-elastic problems are solved by a cell-based smoothed radial point interpolation method (CS-RPIM). For this method, the problem domain is first discretized using triangular cells, and each cell is further divided into smoothing cells. The field functions are approximated using RPIM shape functions which have Kronecker delta function property. The system equations are derived using the generalized smoothed Galerkin (GS-Galerkin) weak form. At first, the temperature field is acquired by solving the transient heat transfer problem and it is then employed as an input for the mechanical problem to calculate the displacement and stress fields. Several numerical examples with different kinds of boundary conditions are investigated to verify the accuracy, convergence rate and stability of the present method.
作者机构：
[朱璞; 毛聪; 张健] Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, China;[周惦武] State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Hunan University, Changsha, China;[张健] Key Laboratory of Efficient and Clean Energy Utilization, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, China
通讯机构：
Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, China
摘要：
Combining first-principles calculations and experimental studies, the influences of doping with transition metals Ti and Ni on the dehydrogenation thermodynamics of magnesium hydride (MgH<inf>2</inf>) were investigated, and the doping mechanism was discussed. The results show that the incorporation of either Ti or Ni decreases the hydrogen desorption enthalpy and initial dehydrogenation temperature of MgH<inf>2</inf>. By contrast, the doping effect of Ni is more notable. The local lattice distortion of MgH<inf>2</inf> induced by dopants is considered to be the main reason for the improved dehydrogenation thermodynamics. Analysis of electronic structures suggests the dehydrogenation thermodynamics of doped MgH<inf>2</inf> is also closely associated with the energy gap near Fermi level and the bonding characteristics of M-H (M = Mg, Ti, Ni) within lattice. Namely, the narrower energy gap and the more obvious covalent bonding characteristics of M-H will correspond to the more excellent dehydrogenation thermodynamics of MgH<inf>2</inf>.
作者机构：
[Mao, C.; Long, C.G.; Tang, K.; Zhang, M.J.] Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, The Education Department of Hunan Province, Changsha University ofScience and Technology, Changsha 410114, China;[Chen, J.] Key Laboratory of Efficient and Clean Energy Utilization, College of Hunan Province, Changsha University of Science and Technology, Changsha 410114, China;[Peng, P.] College of Materials Science and Engineering, Hunan University, Changsha 410082, China;[Zhang, J.] Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, The Education Department of Hunan Province, Changsha University ofScience and Technology, Changsha 410114, China<&wdkj&>Key Laboratory of Efficient and Clean Energy Utilization, College of Hunan Province, Changsha University of Science and Technology, Changsha 410114, China
通讯机构：
[J. Zhang; C. Mao] K;Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, The Education Department of Hunan Province, Changsha University ofScience and Technology, Changsha 410114, China<&wdkj&>Key Laboratory of Efficient and Clean Energy Utilization, College of Hunan Province, Changsha University of Science and Technology, Changsha 410114, China<&wdkj&>Key Laboratory of Lightweight and Reliability Technology for Engineering Vehicle, The Education Department of Hunan Province, Changsha University ofScience and Technology, Changsha 410114, China
