Papers by Keyword: Speed Ratio

Abstract: The article presents the results of experimental investigations of rotor wheels supersonic microturbines with a large angle of rotation of the flow. The characteristics of the studied rotor wheels. The analysis of the results of the study ratio speed of rotor wheels, depending on the Mach number. Recommendations for the design working wheels microturbines operating at high supersonic gas flow rates.

Abstract: Asymmetric rolling of deformed magnesium alloys sheet can accelerate refine the grain size, reduce the basal texture, and improve the subsequent formability. This happens because the additional shear stress and strain are introduced during the differential speed rolling. This paper investigates the relationship of shear stress and microstructure evolution by the experiment in conjunction with the FEM (Finite Element Method) simulation. The differential speed ratio (1, 1.2 and 1.5) and rolling reduction (8% and 15%) were executed at room temperature. The additional shear strain field is simulated for corresponding asymmetric rolling conditions. The results showed that the additional shear stress and strain were the essential influence factors of microstructure evolution and formability of AZ31 sheet for the differential speed rolling. It is helpful in enhancing and improving the formability of rolled magnesium alloys.

Abstract: The review of research methods nozzles. Describes the experimental setup for studying the nozzles. Presents a methodology of the experiment and data processing of the results.

Abstract: Yarns respectively produced by gill pin taker-in and saw-tooth taker-in under different speed ratios were tested by Premier PT7000 evenness tester. The results show that under the experimental conditions, a smaller speed ratio is helpful for the improvement of the yarn quality. Since the main factors of fiber transfer from the taker-in are the centrifugal force and the airflow action, simply discussing the effect of the speed ratio on yarn quality is meaningless. The taker-in speed should first insure that fibers have enough centrifugal forces, which must be definite for discussing the speed ratio. Under the conditions of ensuring well fiber transfer and certain carding degree, speed ratio discussion makes more sense.

Abstract: This paper analyses distribution of the total speed ratio of two-stage helical gear reducer. On the minimum mass and contact strength condition , the optimum speed ratio equation is derived. By means of the least square method, the fitting formula of calculating optimum speed ratio on minimum mass candition is obtained. Using this formula, the optimum speed ratio of two-stage helical gear reducer having minimum mass can be found quickly and accurately.

Abstract: Electromechanical control CVT (EM-CVT) is a new type of continuously variable transmission, and its ratio quality is an important parameter validated the performance of vehicle. In order to study the dynamical coupling technology between EM-CVT and engine under the running state of vehicle, the special character of two working models is obtained by engine experiment; according to the principle of the EM-CVT, the relation between vehicle speed and ration is theoretically analyzed. Based on the basic theory of PID control, the improved PID control algorithm is proposed for the speed ratio control of the EM-CVT, and experimental verification is made. The experimental results show that there is a significant effect on the system with this algorithm.

Abstract: The calculating model of surface non-uniformity of polishing pad and the kinematical model between polishing pad and conditioner are initially established. Then the effects of several conditioning parameters were investigated by using the two models. The results of simulation and calculation show that the width ratio of diamond band of conditoner and the rotation speed at the same speed ratio between pad and conditioner have little effect on the surface non-uniformity of polishing pad, while at high non-integer rotation speed ratio, the surface non-uniformity of polishing pad is better than that at low integer speed ratio. The research results are available to select appropriate conditioning parameters especially for the stringent requirement of within-wafer non-uniformity in next generation IC.