Advanced Materials Research Vols. 986-987

Abstract: Mechanical expanding is widely used in production of large diameter submerged-arc welding pipes. To improve welded pipe quality, it is necessary to investigated effects of geometry parameters on mechanical expanding forming process. So, effects of geometry parameters on mechanical expanding is obtained using finite element method.. Taking the expanding of X80 steel Φ1219mm×22mm×12000mm welding pipe for instance, the mechanical expanding forming process is simulated by finite element (FE) code ABAQUS. In this paper, the simulation data is validated by experiments and a comparison showed a good agreement with experiments results. The effects of geometry parameters on mechanical expanding are discussed. Thus, the result of research provides a basis to improve welded pipe quality.

Abstract: M10, M15, M50 methanol gasoline and 93 # gasoline engine emission performance test were researched on the engine GW491QE. Always stayed in 60 N·m torque and rotational speed increased from 1000 r/min to 3000 r/min, recorded the corresponding data, performance, emission performance curve was drawn respectively, comparison and analysis, the influencing factors of GW491QE engine emission performance were discussed, practical application on engine GW491QE suitable blending ratio of methanol gasoline was chosen. The experimental results show that: three kinds of methanol gasoline of HC emissions is lower, M15 improvement is most obvious; NOx emissions are reduced. GW491QE engine emission performance is taken into account, M15 methanol gasoline is a good proportion of the actual application.

Abstract: Using finite element method to simulate complex operations of the whole condenser under extreme water pressure, this paper aims at predicting the strength and stiffness of the condenser components under extreme pressure conditions. The results show that the max stress of the components is less than the allowable stress, and the max deformation is also within the permitted scope. The results will provide necessary reference for the further optimization design of condenser.

Abstract: The HE (heat exchanger) of automotive exhaust TEG (thermoelectric generator) plays a vital role in converting thermal energy into electrical energy, therefore achieves the goal of energy conservation and emission reduction. A new regular-octagon HE is modeled and simulated in FLUENT to obtain the velocity path-lines of fluid. Through simulation results, the velocity path-line is tracked and analyzed, in order to evaluate the fluid resistance and fluid turbulence intensity. By using control variable method, a variety of HE models with different structural parameters are modeled and simulated, to optimize the structure of HE. Eventually, it is intended to design a HE with proper fluid resistance and remarkable turbulence intensity.

Abstract: We present a novel solution to accurately recover 3D dynamic flame temperature field based on physical parameters consistency. First, a new optical model is proposed to establish the relationship between the flame radiation and the radiance field, this model fully considers refractive effect caused by refraction index changing; Second, high dynamic range (HDR) cameras are used to take flame images, a lookup table is employed calculate temperature from radiance; Third, an algorithm is put forward to reconstruct the flame temperature field. Experimental results on real flame accord with physical facts, which demonstrate that our solution is validate.

Abstract: Aiming at the test of Aero-engine bearing is expensive, small sample without failure, and bearing life obeys Weibull distribution, small sample data is introduced in order to estimate the reliability of bearing with the method of Bayesian point estimation. The weighted least squares method is utilized to estimate the shape and scale parameters of Weibull distribution in the case of no failure. The bearing cumulative failure function, failure rate and average life can be gotten. Finally, the bearing experiment data is used to verify the validity of the small sample evaluation. It is proved that the method has an important value for the replacement and maintenance of Aero-engine bearing.

Abstract: Since the first hydraulic mechanical erosion discovered in the later stage of 19^th century, researchers from both abroad and home have devoted a large amount of time and energy, ranging from fluid dynamics of multiphase systems and dynamics of materials to design of impeller, processing craft and material application with multi-subject research.

Abstract: Theresistance of slurry pipelinetransportation has greatly impact on slurry transportation system. In order toimprove transportation efficiency,energy utilization rate,taking theappropriate drag reduction technology has a very important significance.Thispaper presents drag reduction technologies for slurry transportationapplications,including micro-bubble drag reduction technology and vibrationdrag reduction technology.

Abstract: In this paper, the AVL-Fire software was used to research the effects of ignition timing on homogeneous combustion and particle emission in a GDI engine. The result shows that the highest temperature and pressure reduce with the delay of ignition timing under the homogeneous charge mode in which gasoline is injected in the intake process. But the soot mass fraction decrease first and increase subsequently.

Abstract: Based on PNGV (the Partnership for a New Generation of Vehicles) equivalent battery model, establishing state-space equations, discrediting them and using UKF (Unsvented Kalman Filtering) arithmetic to achieve an exact SOC estimation under the non-linear condition. According to simulation experiment, UKF estimation just has an error rate of less than 6 percent, and has a quite high use value.