Applied Mechanics and Materials Vols. 433-435

Abstract: A geometric model and finite element grid model of JQ40A gasoline engine turbocharger were set up based on the CFD software NUMECA. And the stress, deformation and vibration modal analysis on turbocharger’s compressor impeller, turbine and integrated turbine box was carried out by software ANSYS. The result shows that thin blade impeller design, weight reduction design of the turbine is beneficial to reducing the maximum structural stress, deformation and rotation frequency. The integrated design of the exhaust manifold and the turbine housing is helpful to reducing the flow resistance and the vibration frequency, so as to effectively avoid the resonance region, ensure turbocharger’s reliability and make for enhancing aerodynamic performance. Research methods and conclusions which are of important theoretical significance and practical value, provide basis for optimization design of turbocharger.

Abstract: The thickness control of lining is vital to the normal operation of converter. Vulnerable parts of the furnace would be found and repaired timely by applying thickness measuring technique by laser. According to the measured results, the load part of the facet of the converter is the weakest location of the lining in the early campaign life, while the section of the trunnion is the weakest in the middle campaign life. When it comes to the later stage of campaign, the erosion of lining is severe. In line with the quantification of erosion parts, the lining thickness range can be divided into three parts, which are safety smelting area, stability control area and dangerous area. The economic life of the furnace life, which is 20 to 23 thousand heats, can be maintained as the thinnest lining is still above the stable range when the campaign reaches mid-late period.

Abstract: A new shape-adaptive compliant tool system is developed in this essay, which can be effectually integrated with industrial robots and five-axis NC machines. The main principle of the above compliant tool system can be described as follows: a passive servo mechanism of bi-directional rotating sphere hinge, working with the robots to control the tool-path which can meet the requirements of the adaptive capability on free-form surfaces. The normal polishing force could be controlled by the designed linear stepping motor and column helix spring system. The virtual prototyping of the tool system is created in ADAMS, and used to take the simulating experiments on workpieces which have typical free-form surfaces. The experimental results indicate that the tool system developed in this essay performs well on shape-adaptive capacity on free-form surfaces.

Abstract: In this paper, the finite element model and mesh model of JQ40A gasoline engine turbocharger compressor was built by using Computational Fluid Dynamics(CFD) software NUMECA. The compression ratio and efficiency characteristics of compressor were simulated and verified experimentally. Based on the established models, the airflow velocity field, pressure field, temperature field and entropy field in the compressor volute passage and impeller clearance were simulated and analyzed. The simulation results show that the pressure loss is low and the flow passage design is reasonable; A rational volute export curvature R does not affect the compressor efficiency; the compressor impeller rim size can be adjusted to accommodate the engine torque characteristics; the engine speed affects internal loss of the flow field; within a certain range the impeller tip clearance is smaller, the higher the efficiency of the compressor is. The research methods and conclusions provide a basis for the optimization design of the compressor.

Abstract: To guarantee the effect of virtual axis machine tool, improve processing quality, research on analyze machining parameter optimization problem on affect the machining accuracy of the virtual axis machine tool, position and pose of the virtual axis machine tool are analyzed, and find out the key factors that affect the position and pose, and progress the actual processing experiment of position and pose for the optimized processing parameters, the results of actual processing proves that the optimized processing parameters can guarantee good processing effect.

Abstract: The Flexible track automatic drilling equipment is widely used in aircraft assembly because of the low cost, high efficiency and high quality of holes. This paper constructs a new flexible track drilling system for large-size aircraft assembly. The system structure is introduced, and the transformation algorithm between product/device coordinate system and axes position parameters is proposed. The experimental results show that the transformation algorithm has the merits of high computational efficiency and high stability, and can meet the requirement of precision drilling.

Abstract: Machine vibration, noise and cylinder barrel wearing are produced when ordinary piston air compressor driven by crank link mechanism is working. Piston air compressor driven by double-crank link mechanism is proposed in this paper to eliminate these problems. Secondary pressurized double-acting air compressor and two-stage double-acting air compressor based on symmetrical double-crank link mechanism are designed in this paper to increase air compressors output pressure and flow rate and to achieve output control of low pressure high flow and high pressure low flow. It can remove effects generated by lateral force, reduce the vibration and noise and the wearing of cylinder barrel, and improve the steadiness and the service life of the air compressor.

Abstract: The primary goal of this research is the development of SLM (selective laser melting) system, which including hardware system and software system (associated control software) .The hardware system is consisted of an YLR-200 Yb-fiber laser, a pre-place powder device, a K100 gas purification system and a CNC system. The software system can be divided into several modules such as STL file loading and viewing, model slicing, fill path generation and process controlling. The pre-place powder device is the most key part of SLM hardware, and its construction and design method were described in this article. The thickness of slice should be adjusted easily and controlled in the range of 0.01~1.0mm by the system, and laser scan velocity can attain 7m/s, and some examples are shown in this article.

Abstract: Using CAD / CAE / CAM softwaresolidworks obtain material barrels three-dimensional model. The analysis date of dropping simulation, the material barrel filled with heavy objects, free-fall from the height of 1.2 meter on non-normal condition, is got by the function of dropping test and the method of equivalent load setting. The result of analysis is very close to the results of the theoretical calculations. It shows that the design to improve product quality and efficiency has a very important theoretical and practical value.

Abstract: According to the research status of spray and drainage technology at home and abroad, based on the basic design of the ejector, this paper designs the ejector geometry, and do numerical simulation and analysis for ejection and combination flow field inside the ejector by using computational fluid dynamics method, building structure design of ejectors with pressure-gain for low-pressure gas wells. Verified by numerical simulation and field tests, the results showed that ejector design method is reliable. The operation of the device at the scene is safe and stable, achieving such goals as using energy from high-pressure wells to drive the low-pressure wells to work stably; delaying pressurization and exploitation for gas wells, reducing the cost of production and management. Field experiment is very effective, providing a new channel for us to increase the pressure of low-pressure gas wells and exploit them.