Eventos Anais de eventos
DINAME 2017
XVII International Symposium on Dynamic Problems of Mechanics
Rocket dynamic loading during road transport in a tractor semi-trailer
Submission Author:
Carlos Souto , SP
Co-Authors:
Carlos Souto, Matheus Romero, Edilson camargo, Domingos Sávio Aguiar
Presenter: Carlos Souto
doi://10.26678/ABCM.DINAME2017.DIN17-0131
Abstract
Solid propellant rocket engines are submitted to dynamic loading during its all lifecycle from launching to flight. Actually, rocket engines are submitted to dynamic loads during its transportation from its factories to its launching sites and each kind of transport (railway, highway, boat, airplane) produce a specific load profile. The loads in transportation phase usually are different from the launching and flight ones, but should also be taken into account in order to prevent damage in the propellant grain. The Institute of Aeronautics and Space (IAE), the organization responsible for rocket development within the Brazilian Space Program, has developed a small satellite launcher VLS (Veículo Lançador de Satélites) capable of insert satellites up to 200 Kg in a Low Earth Orbit. This launching vehicle was composed by six S43 and one S44 solid rocket engines. The VLS should be launched on Alcântara base in Maranhão. In a typical VLS launching mission, the solid propellant is loaded in the rocket engine cases (manufactured in another site) in an IAE facility in Jacareí, São Paulo. After that the engines are carried by a truck to São José dos Campos airport where are shipped into a military cargo aircraft to São Luís, Maranhão. Finally it is carried by truck again to Alcântara base where the VLS is assembled by connecting properly the S43 engines, the S44 engine the payload and other launcher components. Since a part of the rocket engines path to its launch site is travelled by road, the dynamic loads which occur in this phase should be evaluated. Mathematical models of many complexity levels of a truck with its cargo can be used to estimate the vehicle response to the excitations caused by the road profile. In this work the vertical dynamics of a tractor-semitrailer with a S43 solid rocket engine as payload was analyzed. A mathematical model of the vehicle was built in a MATLAB routine. The model for the whole vehicle was obtained by considering the tractor and the semi-trailer as rigid bodies connected by the fifth wheel. The vehicle response to some obstacles on the road (described by time domain functions) and to some road quality profiles (described by power spectral density functions) was calculated. The influence of some vehicle parameters (like tire and suspension properties) on the dynamic response of the semi-trailer center of mass was estimated. The estimated rocket’s vibrations during the road transport were compared to literature similar results.
Keywords
Vehicle Dynamics, tractor-semitrailer, rocket transportation loads
