The oscillatory flow through tapered cylindrical tube sections (jet pumps) is characterized by a numerical parameter study. The shape of a jet pump results in asymmetric hydrodynamic end effects which cause a time-averaged pressure drop to occur under oscillatory flow conditions. Hence, jet pumps are used as streaming suppressors in closed-loop thermoacoustic devices. A two-dimensional axisymme...

OBJECTIVES We sought to investigate the effect of a catheter-mounted microaxial blood pump (Impella, Aachen, Germany) on myocardial infarct size. BACKGROUND The small rotary blood pump Impella provides unloading of the left ventricle and is introducible via the femoral artery. METHODS Myocardial infarction was induced by occlusion of major branches of the left anterior descending coronary a...

The mid-latitude atmosphere is dominated by westerly, nearly zonal flow. Occasionally, this flow is deflected poleward by blocking anticyclones that persist for 10 days or longer. Experiments in a rotating annulus used radial pumping to generate a zonal jet under the action of the Coriolis force. In the presence of two symmetric ridges at the bottom of the annulus, the resulting flows were near...

The evaluation of hydraulic constants is generally one of the main components of reservoir engineering projects such as the development of radioactive waste disposal sites or the construction of underground CO2 storage. In the example presented here, flow pump experiments were conducted for the Horonobe mudstone to evaluate specific storage and hydraulic conductivity. The flow pump experiments ...

An analytical model for electroosmotic flow rate, total pump current, and thermodynamic efficiency reported in a previous paper has been applied as a design guideline to fabricate porous-structure EO pumps. We have fabricated sintered-glass EO pumps that provide maximum flow rates and pressure capacities of 33 ml/min and 1.3 atm, respectively, at applied potential 100 V. These pumps are designe...

This paper deals with the design and performance analysis of centrifugal pump. In this paper, centrifugal pump is analyzed by using a single-stage end suction centrifugal pump. Two main components of a centrifugal pump are the impeller and the casing. The impeller is a rotating component and the casing is a stationary component. In centrifugal pump, water enters axially through the impeller eye...

OBJECTIVE One of the major damage caused by occlusion in roller pumps is hemolysis. Comparative studies between roller pump with adjustments non occlusive and centrifugal pumps have been made in recent decades in an attempt to develop new products and adjustments that cause fewer traumas to the figurative elements of blood. Usually the roller pumps are adjusted by the static method due to conce...

OBJECTIVES The aim of this study was to determine the contribution of pre-load and heart rate to pump flow in patients implanted with continuous-flow left ventricular assist devices (cfLVADs). BACKGROUND Although it is known that cfLVAD pump flow increases with exercise, it is unclear if this increment is driven by increased heart rate, augmented intrinsic ventricular contraction, or enhanced...

OBJECTIVE In a univentricular Fontan circulation, modest augmentation of existing cavopulmonary pressure head (2-5 mm Hg) would reduce systemic venous pressure, increase ventricular filling, and thus substantially improve circulatory status. An ideal means of providing mechanical cavopulmonary support does not exist. We hypothesized that a viscous impeller pump, based on the von Kármán viscous ...

BACKGROUND Hemodynamic assistance with a miniature intracardiac pump may fill the treatment gap between use of an intraaortic balloon pump (IABP) and the current, more invasive ventricular assist devices. The objective of this study was to compare the hemodynamic efficacy of a miniature intracardiac pump device with that of IABP. METHODS AND RESULTS Reversible acute mitral regurgitation (AMR)...