This paper proposes a control system for integrated pressure and surge control of centrifugal compressors for enhanced oil recovery application. The proposed control system is based on linear model predictive control. A fully validated non-linear dynamic model was developed in order to simulate the operation of the compressor at full and partial load. The model of the compression system include...

This paper introduces the indicators for surge arrester condition assessment based on the leakage current analysis. Maximum amplitude of fundamental harmonic of the resistive leakage current, maximum amplitude of third harmonic of the resistive leakage current and maximum amplitude of fundamental harmonic of the capacitive leakage current were used as indicators for surge arrester condition mon...

Computer modeling with the EMTP code has been applied to several configurations and earthing practices in use in various countries to show the effect of any differences in the dispersion (sharing) of a lightning stroke current among the available paths for the earth-seeking lightning current. Simplifying assumptions have been made to some details of the configurations to focus on the main diffe...

The application of surge-protective devices in lowvoltage systems faces the dilemma of providing effective limiting against surges while not attempting to limit the temporary overvoltages that do occur in a power system The paper illustrates this dilemma with specific scenarios and presents recommendations for reconciling these two conditions through adequate design and more explicit standards.

In his article "Possibilities and Limits of Comparative Literature Today" Darío Villanueva discusses the itinerary of comparative literature and its problematics and queries the discipline's adherence to literary history and its identification with the theory of literature. Villanueva's discussion is with particular reference to Spanish-language works such as by Claudio Guillén's systemic view ...

We show an application of the method of extremum seeking to the problem of maximizing the pressure rise in an axial flow compressor. First we apply extremum seeking to the Moore–Greitzer model and design a feedback scheme actuated through a bleed valve which simultaneously stabilizes rotating stall and surge and steers the system towards the equilibrium with maximal pressure. Then we implement ...

s y t g I o p l w g n c trial fibrillation (AF) is a common complication in paients undergoing major thoracic surgery (1–3). It is most requently observed acutely after valve surgery and/or coroary artery bypass graft surgery (CABG), but it can also anifest after lung and heart transplantation procedures 1–7). Although mechanisms underlying this unique form f AF have not been adequately elucida...

When fluid flow in a pipeline is suddenly halted, a pressure surge or wave is created within the pipeline. This phenomenon, called water hammer, can cause major damage to pipelines, including pipeline ruptures. In this paper, we model the problem of mitigating water hammer during valve closure by an optimal boundary control problem involving a nonlinear hyperbolic PDE system that describes the ...