Applied Mechanics and Materials Vols. 105-107

Abstract: By means of the finite differential method, the Reynolds equation is solved and the static characteristics of herringbone grooved hydrodynamic journal bearing are numerically analyzed by presenting the circumferential and axial pressures. The influences of parameters such as the eccentricity, width-diameter ratio of bearing, spiral angle, depth and number of grooves, on the static characteristics of herringbone grooved bearing are discussed. The results indicate that the normal pressure of oil film and the load carrying capacity as well, of herringbone grooved bearing will decrease with the increase of groove number and depth. On the other hand, as the pressure distributes in wider area in the circumferential direction, the stability of bearing can be improved. In consideration of these two aspects, the optimal groove number is 8-12, and the selection of depth and screw angle of grooves should also be chosen carefully to obtain the significant performance of herringbone grooved bearing.

Abstract: Profile is the most important base in double-action compressor design. Different cylinder profile decides different working chamber volume in double-action sliding vane compressor. Five equations of cylinder profile were researched by calculating the working chamber volumes and a new cylinder profile equation of double-action sliding vane compressor was composed to get larger chamber. In same condition with the other equations, the working chamber volume of new profile is bigger than the old profiles over 20 percent while it has no change in the moving and friction characters. And a three dimensional model based on SolidWorks of a new profile was done. Finally, it was assembled successfully in computer to check the design.

Abstract: As the water flowing through a reservoir, the floating probably stays in somewhere. Sometimes the floating can be breathed into the mouth of power engine and may do harm to the engine. Most time it will populate the water. So the floating must be selected in time. This machine can be fixed on the bank, grab floating and move along with tracks to grab in larger area. It can work efficiency, grab the floating in some dangerous area ahead the dam. The design is combined the structure of arm crane and the caterpillar tread crane, and loads analysis is according to the worst condition. All calculation results passed the stability check.

Abstract: Owing to the deficiency of machining non-circular curve by manual programming in CNC system, the universal macro-program of machining non-circular curve based on the ellipse curve in CNC turning of the FANUC system is developed by adopting analytical and inductive approach. The real application of machining ellipse and parabola curves are also proposed in this paper, which showed that the universal macro-program is flexible and convenient. The programming efficiency and quality is increased effectively while machining any other non-circular curve works.

Abstract: . The (2,1)-total labelling of the tree has been widely studied. In this paper we study the (3,1)-total labelling number of the tree. The (3,1)-total labelling number of the tree is the width of the smallest range of integers to label the vertices and the edges such that no two adjacent vertices or two adjacent edges have the same labels and the difference between the labels of a vertex and its incident edges is at least 3. We prove that if the distance of the maximum degree in the tree is not 2, then the (3,1)-total labelling number is the maximum degree plus 3.

Abstract: Arched Corrugated Steel Roof (ACSR) is a kind of thin-shell steel structure. Although it has many advantages, the characteristics of little span and low carrying capacity make such structure a very narrow range. This paper take an example with an arched corrugated steel roof of the 35.6 m span constructed with traditional way but the bearing capacity can't meet the design requirements, puts forward two enhanced measures, namely design the arch into fixed end support or set concrete cantilever beam to reduce arch span, then respectively analyze the two enhanced measures with finite element analysis software ABAQUS and ACSR software, finally get the maximum stress ratio and displacement of the structure, and consider setting concrete cantilever beam as the most appropriate measure to the project. The result of this paper provided beneficial reference for the application of the same type structures.

Abstract: An application of high speed on-off valve which is connected between rod cavity and no-stem cavity of hydraulic cylinder was designed to study the speed control problem when the motion state of hydraulic cylinder is transformed. Research result shows that HSV can reduce the maximum starting acceleration and the final velocity effectively, and can realize the speed control when the motion state of hydraulic cylinder is transformed.

Abstract: This paper provide two methods to analyze the cogging torque of PM motor with radial magnetic field and parallel magnetic field, FEM method and Analytic method. The FEM model and Analytic model of PM motor with radial magnetic field and parallel magnetic field are founded. We analyze the model in both methods. From the result of analysis. The air-gap magnetic density of PM motor can be analyzed. We can find the cogging torque of radial magnetic field PM motor is much heavily than the cogging torque of parallel magnetic field PM motor. The result of Analytic method is close to the result of FEM method. The Analytic method is useful in analyze the cogging torque of PM motor.

Abstract: In the last decades, many methods of ANSYS finite element modeling have been proposed. By comparing the two different methods of beam element modeling and entity unit modeling for multistage centrifugal pump rotor, we find that although both methods are insensitive to torsional vibration model, to some extent they affect other vibration models and result in certain deviation in calculation results. Using beam element modeling not only improves the calculation precision, but also saves computing resources. The Appropriate selection of the element type will reduce the amount of input data and computation time.

Abstract: Clonal selection algorithm is improved and proposed as a method to solve optimization problems in iterative learning control. And a clonal selection algorithm based optimal iterative learning control algorithm with random disturbance is proposed. In the algorithm, at the same time, the size of the search space is decreased and the convergence speed of the algorithm is increased. In addition a model modifying device is used in the algorithm to cope with the uncertainty in the plant model. In addition a model is used in the algorithm cope with the uncertainty in the plant model. Simulations show that the convergence speed is satisfactory regardless of whether or not the plant model is precise nonlinear plants. The simulation test verify the controlled system with random disturbance can reached to stability by using improved iterative learning control law but not the traditional control law.