The response time of a rotor system on a magnetorheological(MR) fluid squeeze film damper was measured experimentally. The effects of rotating speed, step voltage and rotor imbalance on the response time were dealt with. It is shown that the MR fluid damper rotor system is a second-order dynamic system. The rapid response time defined by the time taken for the vibration amplitude to rise (fall) from 10 % (or 90%) to 90 % (or 10%) of the vibration amplitude difference between the initial and final states is 0.05~0.7s in applying a step voltage and 0.01~1.225s in dropping a step voltage, respectively. It is impossible for the response time to be within a few milliseconds. The response time is determined not only by magnetic field strength, MR fluid specification, rotational speed, but operation mode of the power supply. There is a zero initial delay time at either applying or dropping the step voltage, which is caused by the magnetizing or de-magnetizing process.

Some computational results on dendritic growth in binary alloy are obtained by using a phase-field model coupled the solute gradient term. The effect of crystalline anisotropy on the morphological formation, tip steady state and the solute partition is investigated for different dendrites. The interface formation and tip steady state are affected evidently with increase in anisotropy for ͗100͘ dendrite growth, but the solute partition coefficient is not significantly influenced. For ͗110͘ preferred growth directions, when the anisotropy strength is lower than the critical value, the tip velocity of [ 1 10]

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Coupling the force flow field with the phase field model for the isothermal growth of dendrite, Sola algorithm is used to calculate the flow speed and pressure of liquid metal, Using double grid numerical method to reduce the calculation amount of computer simulation, The space factor and time factor are introduced to improve the accuracy of double grid numerical calculation, Taking Al-2%-Cu alloy as an example, the dendrite growth process of the binary alloy under forced convection environment is simulated; The simulation results can capture the real dendrite growth and interactions of the liquid metal flow in the process of dendrite growth under forced convection environment: In the incident flow regions, the dendrite morphology is complex, the secondary dendrite is lush and the growth speed is fast due to the influence of liquid metal flow. In the back flow regions, the growth of dendrite changes the flowing pressure among the liquid metals, it causes the regional complex flow patterns and there are two opposite eddy current; the grow speed of the main branch which grows perpendicular to the initial flow direction is the fastest and presents tilt growth phenomenon. When the space coefficient value is appropriate, the dual mesh method can save calculation time effectively.

Based on the location of the routing protocol because it avoids the shortcomings of flooding mechanisms and has a good scalability, become research focus in frequent changes network topology VANET .GPSR based on node location only for data forwarding, so it is important to vehicle node location information is accurate, directly affect the normal data forwarding. For GPSR algorithm the destination node location inaccuracy problem, this paper introduces the concept of expectation domain to estimate the location of the destination node movement range, and the last hop neighbor node selection of the destination node to join discriminant mechanism. The simulation experimental results show that the improved GPSR protocol has a higher packet delivery rate.