“…Considering the sensitivity of passengers to vertical accelerations while aligning with the actual operating speed of the elevator test tower, the parabolic velocity profile established by Zhang et al (2019b) was used, as shown in Figure 3. For this curve, v1=0.9375normalm/normals,v2=5.9625normalm/s,vm=6.9normalm/s,h1=87.63normalm.…”
Section: Methodsmentioning
confidence: 99%
“…For this curve, v1=0.9375normalm/normals,v2=5.9625normalm/s,vm=6.9normalm/s,h1=87.63normalm. The operation state change for the elevator car is shown in Table 2.Figure 3.Speed change curve for the elevator car (Zhang et al, 2019b). …”
Section: Methodsmentioning
confidence: 99%
“…Under actual operation conditions, a car moves vertically in the hoistway and experiences acceleration, uniform speed, and deceleration processes in turn. The hoistway fluid produces different changes under the induction of the continuous variable-speed motion of the car (Zhang et al, 2019b), so its effects on the car’s horizontal vibration are also different. Therefore, the above research solely focused on the uniform speed operating process of high-speed elevators cannot accurately describe the horizontal vibration response of the car body throughout the whole operating process.…”
High-speed elevator cars affected by external excitations exhibit complex horizontal vibration responses during their entire operating processes. To accurately explore the horizontal vibration response of a car and the response differences between the operating processes, a gas–solid coupling model for the entire high-speed elevator operating process was developed based on the finite volume method, Lagrange’s theorem, and the external excitations obtained from dynamic mesh technology and the time-variant guideway excitation simulation method. The differences in the car’s horizontal vibration acceleration and the effect of the fluid load disturbance during different high-speed elevator operating processes were analyzed by considering the different operating characteristics of the car during its acceleration–uniform speed–deceleration process. The feasibility of the model and modeling method were verified by testing an actual 7 m/s high-speed elevator. The results showed that the horizontal vibration acceleration of the car reached its maximum value during the uniform speed process, and the shaft fluid pressure load had the most significant effect on the horizontal vibration response of the car during the deceleration process.
“…Considering the sensitivity of passengers to vertical accelerations while aligning with the actual operating speed of the elevator test tower, the parabolic velocity profile established by Zhang et al (2019b) was used, as shown in Figure 3. For this curve, v1=0.9375normalm/normals,v2=5.9625normalm/s,vm=6.9normalm/s,h1=87.63normalm.…”
Section: Methodsmentioning
confidence: 99%
“…For this curve, v1=0.9375normalm/normals,v2=5.9625normalm/s,vm=6.9normalm/s,h1=87.63normalm. The operation state change for the elevator car is shown in Table 2.Figure 3.Speed change curve for the elevator car (Zhang et al, 2019b). …”
Section: Methodsmentioning
confidence: 99%
“…Under actual operation conditions, a car moves vertically in the hoistway and experiences acceleration, uniform speed, and deceleration processes in turn. The hoistway fluid produces different changes under the induction of the continuous variable-speed motion of the car (Zhang et al, 2019b), so its effects on the car’s horizontal vibration are also different. Therefore, the above research solely focused on the uniform speed operating process of high-speed elevators cannot accurately describe the horizontal vibration response of the car body throughout the whole operating process.…”
High-speed elevator cars affected by external excitations exhibit complex horizontal vibration responses during their entire operating processes. To accurately explore the horizontal vibration response of a car and the response differences between the operating processes, a gas–solid coupling model for the entire high-speed elevator operating process was developed based on the finite volume method, Lagrange’s theorem, and the external excitations obtained from dynamic mesh technology and the time-variant guideway excitation simulation method. The differences in the car’s horizontal vibration acceleration and the effect of the fluid load disturbance during different high-speed elevator operating processes were analyzed by considering the different operating characteristics of the car during its acceleration–uniform speed–deceleration process. The feasibility of the model and modeling method were verified by testing an actual 7 m/s high-speed elevator. The results showed that the horizontal vibration acceleration of the car reached its maximum value during the uniform speed process, and the shaft fluid pressure load had the most significant effect on the horizontal vibration response of the car during the deceleration process.
“…Therefore, it is necessary to utilize new modeling methods to ensure the accuracy of the model and to be as simple and efficient as possible, thereby providing an accurate and practical model basis for the next step in researching vibration control methods. In our previous study [8], the main factors causing the horizontal vibration of high-speed elevator cars were rail irregularity and unsteady air flow represented by piston wind. The vibration under the influence of such complex coupling factors determines the complexity and accuracy requirements for the control method.…”
“…Zhang et al 7 established a three-dimensional geometric model of the vent and the car; analyzed the influence of the vent's number, position, and cross-sectional area on the airflow movement; and discussed the optimal opening position of one or two pairs of vents. Zhang et al 8 deduced a general theoretical model of unsteady airflow in multi-vent hoistways and analyzed the influence of different vent parameters on airflow. Park et al 9 used ANSYS CFX software, and the effect of elevator movement on the pressure difference between the vestibule and the living room under the control of the smoke control system was numerically analyzed, and it was found that the higher the elevator speed, the higher the pressure difference between the vestibule and the living room.…”
When the ultra-high-speed elevator car-counterweight system runs opposite each other, significant piston effects are caused, seriously affecting the elevator operation's stability. In order to explore the aerodynamic characteristics of the whole operation process of a car-counterweight system under multi-parameters, this study first establishes a three-dimensional transient model of the car-counterweight system and a multi-region dynamic layering numerical simulation method based on this model is proposed. Then, the actual elevator experiment validates the correctness of the model and the method. Finally, the influence rules of key parameters on the car's aerodynamic characteristics and ventilation effect are analyzed, and the car's aerodynamic characteristics at intersection time are analyzed emphatically. The results show that with the increase in the blocking ratio, the pressure drag and viscous drag have similar change trends at each stage, but the influence of pressure drag is more significant. The air displacement ratio increases by 34.1%, 75.8%, and 117.3%, respectively. With the increase in the hoistway height, the air displacement ratio decreases by 0.9%, 2.4%, and 2.9%, respectively. The spacing significantly affects the car's aerodynamic characteristics at the intersection time. The drag peak increases by 6.8%, 13.6%, and 20.5% and the lift peak by 21.2%, 47.8%, and 82.5%, respectively.
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