In order to reduce the mass, the new designs of turbojet engines use rotors working with higher speeds. These rotors are subjected to large unbalance during engine operational conditions. An additional damping might be necessary in order to enable working at rotation speeds higher than the critical ones. In order to achieve this objective, Integral S-shaped Squeeze Film Damper (ISSFD) and Multi...

Abstract The simulations and assessment of transient performance gas turbine engines during the conceptual preliminary design stage may be conducted ignoring heat soakage tip clearance variations due to lack detailed geometrical structural information. As a result, problems with stability not revealed correctly, corresponding iterations would necessary costly when those are at stage. To make an...

A novel approach is presented in this article for obtaining inverse mapping of thermodynamically Pareto-optimized ideal turbojet engines using group method of data handling (GMDH)-type neural networks and evolutionary algorithms (EAs). EAs are used in two different aspects. Firstly, multi-objective EAs (non–dominated sorting genetic algorithm-II) with a new diversity preserving mechanism are us...

In this article, an exact analysis of compressors spool in a turbojet engine has been investigated. The spool is modeled as a rotating thick-walled hollow circular cylinder with free-clamp ends. It is subjected to centrifugal load due to its constant rotational speed, uniform internal and external radial loads and arbitrary thermal gradients. The analysis is initially investigated for the homog...