Many papers discuss the voltage stability assessment of power system using power flow analysis methods. In this paper, a method for online monitoring of a power system based on measurements is proposed, which is aimed at detection of the voltage instability. Thereby an indicator is derived from the fundamental Kirchoff-Laws. Since in the transient process, at any time point, the electric power ...

The relative sliding motion of two elastic bodies in contact induces wear process and contact shape evolution. The transient process tends to a steady state occuring at fixed contact stress and strain distribution. This state corresponds to the minimum of the wear dissipation power. The optimality conditions of the functional provide the contact stress distribution and the wear rate compatible ...

in order to present a new and high performance structure of pem fuel cell and study the influence of the flow direction and distribution on the rate of reactants diffusion, three novel models of vertical reactant flow injection into the anode and cathode reaction area field have been introduced. they consist of one inlet and two inlets and also a continuous channel. the governing equations on t...

this paper deals with new method for designing the tuned mass dampers (tmd) with considering both transient and steady state responses, simultaneously. this formulation is presented for undamped vibrations. for this purpose, the absolute value of the structural displacement ratio is minimized numerically. this procedure leads to optimum value of tmd's specifications. for numerical verification,...

Based on the knowledge of dynamic systems, the shorter the transient response, or the faster a system reaches the steady-state after the introduction of the change, the smaller will be the output variability. In lean manufacturing, the principle of reducing set-up times has the same purpose: reduce the transient time and improve production flow. Analogously, the analysis of the transient respon...

  Unsteady flow separation on the airfoils with local flexible membrane (LFM) has been investigated in transient and laminar flows by the finite volume element method. A unique feature of the present method compared with the common computational fluid dynamic softwares, especially ANSYS CFX, is the modification using the physical influence scheme in convection fluxes at cell surfaces. In contr...

Steady-state isotopic-transient kinetic analysis (SSITKA) is a very useful technique for the kinetic study of heterogeneous catalytic reactions. Initially developed by Happe1,l Bennett,2 and Biloen? SSITKA has been used in a number of studies to determine in situ kinetic information about the reaction mechanism and the catalyst-surface reaction intermediates. The technique is based upon the det...

In this work dynamic recrystallization behavior of AISI 403 martensitic stainless steel was studied using hot compression tests over temperature range of 900 C -1200 C and strain rate range of 0.001 s-1 - 1 s-1. The obtained flow curves showed that the hot compression behavior of the alloy is controlled by dynamic recrystallization. The flow stress and strain corresponding to the critical, pe...

Data are presented to show the transient response of a proton exchange membrane fuel cell (PEMFC) subjected to change in the load. Overshoot and undershoot behaviors of the steady-state current density were observed for various rates of change in the voltage during constant inlet flow rate conditions. The results of these experiments with a 25 cm2 triple serpentine flow field indicate a correla...