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...

In a hydroelectric power plant or in a pumping station in order to avoid sudden large increase of pressure due to instantaneous valve closure sometimes a surge tank is installed. The height of surge tank is designed by the highest possible water level during the operation. The theoretical treatment of oscillation in a surge tank is difficult because of the non-linearity of friction term in the ...

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 ...

Abstract. We investigate the aerodynamics of a surging, heaving, and yawing wind turbine with numerical simulations based on free-wake panel method. focus UNAFLOW (UNsteady Aerodynamics FLOating Wind turbines) case: surging which was modeled experimentally various methods. Good agreement experimental data is observed for amplitude phase thrust surge motion. achieve results wake that accurately ...

surge is one of the two destructive factors in compressors. surge is the stream instability phenomenon in compressor that imposes severe damages to the compressors. nowadays, suppressingsurge phenomenon is one of the most important issues in oil and gas industries, especially when flow reduction or gas reflux is considered. according to moore-greitzer compressor model, this paper designs an act...

Abstract: Aerodynamics and motion performance of the floating vertical wind turbine (VAWT) were studied in this paper, where the wind turbine was H-type and the floating foundation was truss spar type. Based on the double-multiple-stream-tube theory, the formulae were deduced to calculate the aerodynamic loads acting on the wind turbine considering the motions of the floating foundation. The su...