Study On The Influence Of Air Resistance On The Dynamic Characteristics Of Indoor Roller Coaster

For the safety of roller coaster and other recreational facilities,the design of roller coaster must be strictly evaluated.The design of outdoor roller coasters has considered the impacts of wind load,snow load and other environmental loads that usually have not been considered for indoor roller coasters.The air resistance is generally not considered in the design.However,the speed of indoor roller coaster can reach more than 70 km / h,and the effect of relative motion is equivalent to the wind load of Grade 7 or more than Grade 7.It is necessary to consider the influence of air resistance in dynamics of indoor roller coaster.This paper calculates the air resistance caused by the relative motion between roller coaster and air,and analyzes the dynamic characteristics of indoor roller coaster with and without relative air resistance,and investigates the influence of relative air resistance on the motion of indoor roller coaster.The main researches of this paper are as follows:(1)The structural model of an indoor roller coaster is built.The car body model is built by UG software and the track model is built by ADAMS.(2)By Appling the loads and motion constraints and selecting the time step,the dynamics of the indoor roller coaster for 12 cases are simulated.The environmental loading cases include the cases with and without air resistance.The manned loadings consist of six cases: no-passenger,full passengers,front unbalance load,rear unbalance load,left unbalance load and right unbalance load.The calculated results are compared with the measured data of Tangshan indoor roller coaster.(3)It is found that the velocity and acceleration decrease when relative air resistance is considered.The drop of the maximum speed is 12.6%,the drop of maximum vertical acceleration is 18.7%,and the drop of maximum horizontal acceleration is 12.87%.In addition,the running time of the case considering the relative air resistance is close to the measured time of Tangshan indoor roller coaster,and the error is only 4.17%.If the relative air resistance is not taken into account,the calculation error of running time can reach more than 14%.The researches of this paper show that,the relative movement of roller coaster and air produced by the high speed of indoor roller coaster,affects the motion of the indoor roller coaster.The design of indoor roller coaster should consider the relative air resistance.