Advanced Materials Research Vols. 97-101

Abstract: A manual fixed fire water monitor of type 100 was designed. The monitor can rotate 360º in horizontal direction. It can rotate from the angle of -40º to the angle of 70º in vertical direction. The monitor spraying position can be adjusted by operating the handwheel and it can also automatically be locked. The flow simulation was completed using Fluent kits. The influence of the flow channel which affects the velocity and pressure field was analyzed. The energy loss was explained. The influence of the flow structure which affects the internal flow's turbulence and outlet velocity was obtained. The experiments were carried out on the test rig. The experimental results accorded with the simulation results in general. The relevant results can verify the reasonableness of the designed fire water monitor. It can provide some theory reference to the further optimization of the monitor design.

Abstract: A multiple fields’ coupled model of new magnetic controlled DC plasma torch, which was used for CVD diamond film, was presented. In this model, the effects of electric field and magnetic field on the flow field and temperature field were taken into account, and the fluid dynamics equations were modified by the addition of some source terms relating to electromagnetic field, such as Lorentz force, joule heating, and radiative cooling. Conversely, the generalized ohm’s law was used to solve the current density, which reflected the effects of flow field and temperature field on the electric field and magnetic field. In addition, the rest Maxwell’s equations and external solenoid magnetic field equation were also modeled. In order to know the effect of external magnetic field on the torch, the current intensity of external solenoid was chosen to simulate its influence on the flow and heat transfer in the torch. Results show that external magnetic field plays a part in stirring the plasma, which is advantageous for the preparation of diamond film. The larger the external solenoid current intensity is, the better the uniformity of the temperature and velocity of plasma is.

Abstract: Fire water monitor plays an important role in the fire fighting. A liqumatic fire water monitor with self-swing device was designed, the working principle and its components were also expounded in detail. The internal flow performance was simulated using fluent software, the influence rules on outlet velocity were analyzed by changing different angles of the monitor head and diameters of the monitor body. At the same time, the experimental tests were also carried out on the test rig. The simulation results accorded with the theory calculations in general. So, the rationality and accuracy of the designed fire water monitor was verified, and the relevant results can also provide a certain theoretical references for the design of other types of fire water monitor.

Abstract: The plate rubber support is widely used in railroad bridge. To analyse its capability of transverse displacement resistance and increase its life-span, the finite element model of profiled plate rubber support is established by nonlinear finite element method. The influence of flex gradient of stiffened steel plate to the function of the plate rubber support is analyzed and the optimal gradient is obtained.The method and conclusions are available for designing of plate rubber support.

Abstract: Incremental forming of sheet metal is difficult to be simulated for its complicated 3D loading path. In this work, an acceptable approach to generate 3D loading path, called “virtual guiding model method” is accomplished. The method, which has the similar idea with the conventional copy mill, is based on FEM and the basic principle of kinematics. With the help of the method, multi-stage incremental forming of a drawing typed square cup was simulated in the FEM software-PAMSTAMP and experimented. Through measuring the thickness distribution the vertical edge of the cup, the most difference between them is less than 0.05mm, which is satisfied with engineering request, and the results shows that the 3D loading path generating method is one of the most effective way to realize the incremental forming simulation.

Abstract: With the development of deep water drilling engineering, marine riser has become the important equipment. With the increase in water depth, the failure of marine riser is very serious, the vibration is the main reason. According to the actual situation, the model of marine is set up, the rule of lateral vibration is obtained. The result is helpful to avoid the phenomena of resonance of marine riser under wave loads.

Abstract: By establishing finite element model of load floor based on the field data, this work evaluated vibration of load floor after isolation measures were taken through effective value of acceleration of vibration. And it demonstrated that the floating floor slab was very useful for vibration isolation for load floor whose buildings have been completed. What’s more, the thesis also provided reference standards for further studies on vibration isolation for load floor caused by large-scale rotating machinery on the floor.

Abstract: The study performs the relation between the Lagrange multipliers and the constraint reaction forces in the multi-body systems. It helps to establish a simple and effective method to deal with the non-smooth factors including friction, contact and collision in multi-body systems. First, a general expression calculating the ideal constraint reaction forces is described by a form of complete Cartesian reference coordinate in a discrete dynamical system. Then, an explicit expression is given in the form of independent general generalized coordinates for a multi-body system. A condition under which the constraint reaction forces can be one-to-one corresponding to Lagrange multipliers is discussed. An example is used to demonstrate the process to realize the condition and the effectiveness of this method.

Abstract: A model based on damaged mechanics is presented to analyze the failure behaviour of coke dry quenching refractory lining under circumstance of multifarious change of temperature by using finite element method. The refractory material behavior can be described by Drucker-Prager Plasticity model for compression and strain softening under tension. The simulation result is consistent with the experiment result. This paper provides a new method for the failure analysis of refractory material. The results can be used to optimize the lining design and the material selection.

Abstract: Crawler cranes are the most expensive and frequently shared resource on construction sites, industries, etc. According to the characteristics of crawler crane, this paper presents a multiple modeling method of crawler crane based on OGRE (Object-oriented Graphics Rendering Engine) and Bullet Dynamic Engine. The multiple model is composed of rendering model, collision model, skeleton model and dynamic model. Based on this modeling method, not only vivid figuration and motion of the crane but also real-time collision detection and distance computation can be achieved.