fluid properties with constant improvement in efficiency have been noticeable as important criteria in drilling operation. the main drilling fluid properties highly depend on utilization of new polymers with high efficiency in drilling fluid composition. in this paper, the performance of a new polymer, called partially hydrolyzed polyacrylamide polymer (phpa), is studied which has recently ente...

free surface sloshing of liquid in a rectangular tank induced by lateral excitation has been studied numericallyand experimentally in this paper. the numerical simulation is carried out based on the volume of fluid (vof) method that provides free surface extraction in such problem. a tank with transparent walls is used to free surface tracking in experimental study while the movement amplitude ...

many diseases are related to cerebrospinal .uid (csf) hydrodynamics. therefore, understanding the hydrodynamics of csf .ow and intracranial pressure is helpful for obtaining deeper knowledge of pathological processes and providing better treatments. furthermore, engineering a reliable computational method is promising approach for fabricating in vitro models which is essential for inventing gen...

Unsteady oscillatory flow of generalized Burgers’ fluid in a circular channel tube in the porous medium is investigated under the influence of time-dependent trapezoidal pressure gradient given by an infinite Fourier series. An exact analytical expression for the solution for the fluid velocity and the shear stress are recovered by using the similarity arguments together with the integral trans...

water soluble amphoteric graft copolymers of polysaccharide were synthesized via grafting of cationic monomer onto the sodium carboxymethylcellulose ()cmc)( and then used as a shale stabilizer in the water-based drilling fluids. accordingly, five types of cmc-graft copolymers with different ratios of acrylamide am)( and diallyldimethylammonium chloride dadmac)( were synthesized. grafting of mon...

in this work, the characteristics of flow and heat transfer of a fluid containing nano particles of aluminum oxide with the water volume fraction (0.1-0.2-0.3)(v/v) percent of the reports. the overall heat transfer coefficient, heat transfer and the average heat transfer fluid containing nano water - aluminum oxide in a horizontal double pipe counter flow heat exchanger under turbulent flow con...

in this paper, nonlinear vibration and instability response of an embedded pipe conveying viscose fluid is investigated. the pipe is considered as a timoshenko beam embedded on an elastic foundation which is simulated by spring constant of the winkler-model and the shear constant of the pasternak-model. the external flow force, acting on the beam in the direction of the flexural displacement is...

effects of some thermo-physical parameters on free convective heat and mass transfer over a vertical stretching surface at lowest level of heat energy in the presence of suction is investigated. the viscosity of the fluid is assumed to vary as a linear function of temperature and thermal conductivity is assumed constant. a similarity transformation is applied to reduce the governing equations i...

Oat (Avena sativa L.) traditionally has been a major crop for feed and forage in Turkey. Theobjective of this research was to study hay yield and quality of oat genotypes harvested at thelate milk stage. One hundred oat varieties of worldwide origin were compared in fieldexperiments in Samsun (northern Turkey) over two growing seasons (2007-2008 and 2008-2009).Significant differences between th...