Newton–Euler equations of multibody systems with changing structures for space applications

Multibody systems with changing structure are considered. These systems have stages in their motion that distinct from each other by degree of freedom (DOF), joint connection structure and joint types. These mechanical systems are common in space application e.g. separation subsystems. Single coordinate set is used to formulate Newton–Euler equations of motion at each stage. Proposed equation form simplifies equations building process for certain stages and whole motion. Numerical experiment was carried out using proposed method.     

The Motion of Coaxial Bodies of Varying Composition on the Active Leg of Descent

The motion of a spacecraft (SC) with double rotation and variable mass on the active leg of its descent is considered. The SC consists of two coaxial bodies. The coaxial scheme is used for gyroscopic stabilization of the SC longitudinal axis by the method of partial spin-up. The equations of spatial motion of coaxial bodies of varying composition are derived and approximate solutions for the angles of spatial orientation are found. The condition of decreasing amplitude of nutation oscillations is obtained, which allows the estimation of efficiency of the stabilization by partial spin-up. The errors in the magnitude and direction of the vector of braking thrust are also determined.__________Translated from Kosmicheskie Issledovaniya, Vol. 43, No. 3, 2005, pp. 224–232.Original Russian Text Copyright © 2005 by Aslanov, Doroshin, Kruglov.     

Improvement of a technological process for ceramic core removal out of internal cavities of aircraft GTE turbine blade castings

A technological process of removing a complex-shaped ceramic core from the interior of GTE thin-walled blade castings is considered. We propose an aluminium oxide-based method for removing a core by leaching accompanied by process intensification with a carboxylic acid additive.     

Prediction of cast gas turbine engine blade quality in industrial environment

A mathematical method for prediction of good cast GTE turbine blade output is presented. The method takes into account a concurrent influence of different factors on the technological process and makes it possible not only to predict the blade quality but also to determine ways of its improvement.