Account of Non-Diagonal d-d-Electron Couplings in CoNi Liquid Alloy
The partial Wills-Harrison effective pair potentials in liquid equiatomic Co-Ni alloy are considered. It is shown that the account of the non-diagonal d-d couplings between electrons leads to similar changes in characteristics of the pair-potential first minimum as for Fe-Co and Fe-Ni equiatomic alloys.
Account of non-diagonal coupling between d electrons at describing the transition-metal pair potentials
In the framework of the Wills-Harrison (WH) model the correction due to the non-diagonal coupling between d electrons in different atoms is suggested. Effect of this correction on the WH effective pair interaction is studied for liquid Fe, Co, and Ni. It is found that our approach gives a shift of the WH pair potential to the right-hand side for all metals under consideration (in most degree for Fe and in less degree for Ni). As a rule, such tendency leads to significant changes in calculating thermodynamic properties.
Computer-Aided System of Virtual Testing of Gas Turbine Engines
The article describes the concept of a virtual lab that includes subsystem of gas turbine engine simulation, subsystem of experiment planning, subsystem of measurement errors simulation, subsystem of simulator identification and others. The basis for virtual lab development is the computer-aided system of thermogasdynamic research and analysis “ASTRA”. The features of gas turbine engine transient modes simulator are described. The principal difference between the simulators of transient and stationary modes of gas turbine engines is that the energy balance of the compressor and turbine becomes not applicable. The computer-aided system of virtual gas turbine engine testing was created using the developed transient modes simulator. This system solves the tasks of operational (throttling, speed, climatic, altitude) characteristics calculation, analysis of transient dynamics and selection of optimal control laws. Besides, the system of virtual gas turbine engine testing is a clear demonstration of gas turbine engine working process and the regularities of engine elements collaboration. The interface of the system of virtual gas turbine engine testing is described in the article and some screenshots of the interface elements are provided. The developed system of virtual gas turbine engine testing provides means for reducing the laboriousness of gas turbine engines testing. Besides, the implementation of this system in the learning process allows the diversification of lab works and therefore improve the quality of training.