Об оптимальном управлении гидрообъёмно-механическим приводом при разгоне маховика

An improving dynamic quality of vehicles and enhanced fuel efficiency are gained thanks to the combined power system (CPS), comprising a main energy source - internal combustion engine (ICE) with an attained level of the power source - and an auxiliary energy source, i.e. an energy storage device (a flywheel).To solve this problem was developed a mathematical model of CPS comprising internal combustion engine and flywheel energy storage (FES) with stepless drive.The stepless drive of the flywheel is made to be hydrostatic mechanical to raise the system efficiency. To reduce the drive weight and simplify the control system in the hydraulic part of the flywheel drive is used only one hydraulic unit being controlled.The paper presents a kinematic diagram of the track-type vehicle equipped with the CPS that has a hydrostatic mechanical drive of the flywheel and a mechanical transmission.A mathematical model of the system comprising an ICE, hydrostatic mechanical drive, and FES with stepless drive has been developed. This mathematical model was used to study the influence of ICE and flywheel drive parameters on the dynamic characteristics of the system.The paper estimates the impact of flywheel energy consumption, pressure in the hydraulic system, and control parameter of hydrostatic mechanical drive on the charging time of FES.The obtained piecewise linear law to control the regulation parameter of the hydraulic unit allows us to minimize the charging time of the flywheel at the short-term stops and in the parking area of a tracked vehicle equipped with a CPS.The causes affecting the performance of ‘ICE – drive – flywheel’ system in the course of the flywheel acceleration are a restricted maximum power of the engine, as well as a limited generating capacity, and a maximum flywheel drive hydro-system pressure.The obtained results allow us to determine rational parameters of the flywheel and the laws of drive control to provide their further optimization, with a tracked vehicle being in motion, under random external effect.С помощью разработанной математической модели получено решение оптимальной зарядки маховика при стоянке гусеничной машины оснащенной комбинированной энергетической установкой, содержащей двигатель внутреннего сгорания и маховичный аккумулятор энергии. Выполнена оценка влияния параметров относительной энергоемкости маховика и гидрообъемномеханического привода, содержащего одну регулируемую гидромашину, на время зарядки маховика. Установлены причины, ограничивающие эффективность действия комбинированной энергетической установки в процессе разгона маховика до максимальной скорости. Полученные результаты позволяют определять параметры маховика и законы управления приводом с целью их дальнейшей оптимизации. DOI: 10.7463/aplts.0216.083789

Close Packing of Atoms, Geometric Frustration and the Formation of Heterogeneous States in Crystals

To describe structural peculiarities in inhomogeneous media caused by the tendency to the close packing of atoms a formalism based on the using of the Riemann geometry methods (which were successfully applied lately to the description of structures of quasicrystals and glasses) is developed. Basing on this formalism we find in particular the criterion of stability of precipitates of the Frank-Kasper phases in metallic systems. The nature of the ''rhenium effect'' in W-Re alloys is discussed.Comment: 14 pages, RevTex, 2 PostScript figure