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Beijing, China

Qin B.,Bei Hang University
ICMET 2010 - 2010 International Conference on Mechanical and Electrical Technology, Proceedings | Year: 2010

Single-cylinder piston engine power constraint (Electric Power Confined Piston Engine) combine the traditional internal combustion engine - generator system and the set of power piston engine as a whole, and directly use traditional internal combustion engines reciprocating motion of the piston. With the fuel combustion energy conversion into electrical energy and output it. Constrained by single-cylinder piston engine power structure and working mechanism of the in-depth study ,it has establish a system and dynamic model on the basis of the power piston engine in the motor part to establish parameters and know the conditions of the power constraint in the linear motor piston engine The finite element model use AVL boost power constraint on the single-cylinder piston engine thermodynamic process simulation, and the combustion chamber gas pressure curve was created. © 2010 IEEE. Source

Qin B.,Bei Hang University
ICMEE 2010 - 2010 2nd International Conference on Mechanical and Electronics Engineering, Proceedings | Year: 2010

The non-leaf shell centripetal turbines are used extensively in vehicle exhaust turbochargers; the function of vortex shell has great influences on turbocharger performance. This paper presents a new way for researching on the three dimensional flow field of vehicle turbocharger, in the process of studying the vortex flow field not only the engine working conditions on the vortex flow field are considered but also the influences of the paddle wheel flow field on turbine scroll field are considered. By using the FLUENT software to make simulation calculation of the three-dimensional flow field within the turbine vortex shell, through the study of change with the change of the engine conditions in mass flow of vortex shell entrance -, temperature and pressure, the flow situation inside the vortex shell flow field, the simulation results show that the volute inlet and outlet boundary conditions is identical with the experiment by analogue computation, so it is feasible to make analogue computation on the vortex shell by FLUENT. © 2010 IEEE. Source

Lu Y.-F.,Bei Hang University | Yin Y.-F.,Bei Hang University
19th International Conference on Industrial Engineering and Engineering Management | Year: 2013

Software testing is becoming a relatively independent activity of software development process. To estimate the cost of software testing is an important part of project management. The researchers have focused on the software cost and treated software testing cost as a part of the total software development cost for several years. Few researchers consider software testing as a separate process to estimate its' cost. This paper proposed a new constructive cost model for software testing project management (CCMST) which contains the main cost divers of software testing. The cost drivers included in this model is more comprehensive than former models. Application case study proved the model is usable and valid. © 2013 Springer-Verlag Berlin Heidelberg. Source

Duan R.,Bei Hang University | Chen Z.,Bei Hang University | Liu L.,Hebei University of Technology
Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science | Year: 2015

A linear analysis method has been used to investigate the instability behavior of the viscoelastic liquid sheets moving in the surrounding ambient gas. The gas boundary layer thickness and the liquid sheet velocity profile were taken into account. The effects of gas and liquid viscosity on the growth rate were revealed. The governing equations were obtained through analysis of the liquid and gas domain and solved using the spectral method. The viscoelastic rheological parameters and some flow parameters have been tested to investigate their influences on the instability of the viscoelastic liquid sheets. The results reveal that the disturbances grow faster for the viscoelastic liquid sheet than Newtonian one with identical viscosity. Moreover, the increases of Weber number, elasticity number, gas Reynolds number, and momentum flux ratio can accelerate the breakup of the viscoelastic liquid sheet. However, the increases of time constant ratio, boundary layer thickness, and liquid Reynolds number have the opposite effects. © IMechE 2014. Source

Meng H.J.,Bei Hang University | Wang Z.L.,Bei Hang University
Applied Mechanics and Materials | Year: 2014

With the development of oil field production demand today, pumping unit is developing towards the direction of energy saving, intelligent. According to the present status of the oilfield, this paper designed a kind of intelligent energy saving pumping unit system, the system acceleration and deceleration process is very short, most of their working time in uniform motion in a stroke, and the beam pumping unit has been alternating deceleration process all the time compared with good energy saving effect. Energy store system is designed, the system not only reduces energy consumption, and make the motors can be started with initial velocity, shorten the motor start-up time, the motor starting current is stable running current of 4 to 7 times, so that reduces the starting current impact. To test this idea, modeling of motor, and the simulation analysis, the results confirmed the idea very well. Finally, in the principle of the pumping unit system prototype experiments, the experimental results show that the pumping unit system has significant energy-saving effect and the intelligent characteristics. © (2014) Trans Tech Publications, Switzerland. Source

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