Mode transitions in a 6 kW laboratory Hall-effect thruster were induced by varying the magnetic field intensity while holding all other operating parameters constant. Ultrafast imaging, discharge current, and thrust measurements were used to characterize the change in discharge channel current density and thruster performance through mode transitions. The modes are described here as global osci...

[1] Young flood channels emanate from Cerberus Fossae, Mars. In order to determine whether subsurface aquifers can discharge water sufficiently fast to explain these flood features, I develop a model that couples groundwater flow in a sub-cryosphere aquifer with flow through a fissure that penetrates from the surface to the aquifer. The model is constrained by estimates of peak discharge, and t...

within the climate change debate and its probable impacts on water resources systems, design and operation of management plans based on the assumption of stationary hydrology may cause serious challenge to accurately predict future supplies. therefore this case study is trying to assess trend in hydroclimatic variables of karkheh rivers upstream by applying modified mann-kendall trend test on l...

Measurement of discharge in open channels is one of the main concerns in hydraulic engineering. The structures used for this aim should be accurate, economical and easy to use. Weirs are among the oldest and most convenient hydraulic structures that have been used in both laboratory and field for flow measurement in open channels. Due to limitations of simple sharp crested weirs, recently compo...

An innovative Volumetric Current Meter (VCM) was designed in order to allow quick velocity measurements in open channels. At first, the coefficient of velocity (Cv) of the device was determined through calibration under different water velocities in the laboratory. The measurement performance was verified by measurements performed in similar flows in irrigation channels using an ordinary curren...

regional analysis is one of the important methods for estimating the low flow in ungagged regions. investigation of the relations between effective factors of hydrological drought is the most important strategy to contrast and reduction of drought losses. in this study to analyze of low flow, the daily discharge data from 20 gauging stations with 25 years period (1988-2012) in the kashafroud ba...

in this paper trends of precipitation and stream flow are analyzed in the atrak river basin in the north khorasan province. normal score linear regression, mann-kendall, and seasonal kendall trend tests were adopted. three precipitation variables and two stream flow variables including total precipitation, maximum daily precipitation, and number of rainy days, mean discharge and peak discharge ...