In this research, hydrodynamics of the Bubble Train Flows (BTF) in circular capillaries has been investigated by Direct Numerical Simulation (DNS).The Volume of Fluid Based (VOF) interface tracking method and streamwise direction periodic boundary conditions has been applied. The results show that there exists an appropriate agreement between DNS and experimental correlation results. The re...

A mathematical model for the prediction of internal recirculation of complex impinging stream reactors has been presented. The model constitutes a repetition of a series of ideal plug flow reactors and CSTR reactors with recirculation. The simplicity of the repeating motif allows for the derivation of an algebraic relation of the whole system using the Laplace transform. An impinging stream...

Introduction In dynamic susceptibility contrast (DSC) MRI, the concentration time curves commonly do not return to baseline after the first pass. In normal brain tissues with intact blood-brain barrier (BBB), the elevated concentration during the recirculation phase could be caused by the intravascular contrast agents. However, when the BBB is disrupted, as the case with brain tumor, both the i...

Five landfills were analyzed to provide a perspective of current practice and technical issues that differentiate bioreactor and recirculation landfills in North America from conventional landfills. The bioreactor and recirculation landfills were found to function in much the same manner as conventional landfills, with designs similar to established standards for waste containment facilities. L...

plastic recycling is the process of recovering scrap or waste plastics and reprocessing thematerial into useful products that sometimes differ completely in form from their original state. an importantissue in plastic recovery and recycling is that plastic waste usually contains a variety of plastics that differ intheir physical and chemical properties. separation of recovered plastics into dis...

Conditions for stagnation, recirculation and ventilation potential of the atmosphere were studied in five argentine cities: Resistencia, Cordoba, Buenos Aires, Mar del Plata and Comodoro ́ Rivadavia, located in different regions of the country. Wind run and recirculation factors were calculated for a 24-h transport time using 2 years of hourly surface measurements of wind speed Ž . and direction...

background the presence of arterio-venous (a-v) fistula recirculation among hemodialysis (hd) patients markedly decrease adequacy of dialysis. objectives the present article summarize some of observations about clinical significance, causes, the most common techniques for measurement, and main source of pitfall in calculation of access recirculation. materials and methods a variety of literatur...

Advances in technology, the desire to minimize blood product transfusions, and concerns relating to inflammatory mediators have lead many practitioners and manufacturers to minimize cardiopulmonary bypass (CBP) circuit designs. The oxygenator and arterial line filter (ALF) have been integrated into one device as a method of attaining a reduction in prime volume and surface area. The instruction...

PURPOSE Veno-venous ECMO is indicated in reversible life-threatening respiratory failure without life-threatening circulatory failure. Recirculation of oxygenated blood in the ECMO circuit decreases efficiency of patient oxygen delivery but is difficult to measure. We seek to identify and quantify some of the factors responsible for recirculation in a simulation model and compare with clinical ...

In this paper, we propose to regulate the output of an autocatalytic bioprocess by means of a recirculation loop. We show that controlling the recirculation flow rate allows the stabilization of a particular output under a constant or even an unknown input flow. Furthermore, we obtain a convergence in finite time with a smooth feedback law Copyright c ©2005 IFAC.