We report our searches for a single tubular tachyonic solution of regular profile on unstable non BPS D3-branes. We first show that some extended Dirac-Born-Infeld tachyon actions in which new contributions are added to avoid the Derrick’s no-go theorem still could not have a single regular tube solution. Next we use the Minahan-Zwiebach tachyon action to find the regular tube solutions with ci...

2014 The concentration distribution of a dilute suspension of neutrally buoyant rigid spheres is investigated theoretically, in the entry flow of a circular tube. The geometrical effects (interaction between the tube mouth and the particles) are discussed. The convective motion of the particles in a boundary layer flow through the tube (Re ~ 1) is analysed. The effect of an additional inertia-i...

The CFD simulation of heat transfer characteristics of a nanofluid ina circular tube under convective heat transferwas considered using the fluentsoftware (version 6.3.26) in the laminar flow. Al2O3nano- particles in water with concentrations of 0.5, 1.0, 1.5, 2 and 2.5% were studied in the simulation. All thermo-physical properties of nanofluids were temperature independent. It was concluded t...