www.physicstoday.org Many experiments seem daunting at first glance, owing to the sheer number of physical variables they involve. To design an apparatus that circulates fluid, for instance, one must know how the flow is affected by pressure, by the apparatus’s dimensions, and by the fluid’s density and viscosity. Complicating matters, those parameters may be temperature and pressure dependent....

In this paper, a numerical solution of an inverse non-dimensional heat conduction problem by spline method will be considered. The given heat conduction equation, the boundary condition, and the initial condition are presented in a dimensionless form. A set of temperature measurements at a single sensor location inside the heat conduction body is required. The result show that the proposed meth...

since knowledge on hydrodynamic torque of a butterfly valve is very important for butterfly valve design, its hydrodynamic torque is investigated in this paper. in reality, the investigation of the loss coefficient and torque from some experiments will take a long time and a lot of money. this paper presents a statistical study of the flow past the butterfly valve in a static analysis using com...

According to the former researcher’s presented relations for flow through rock-fill porous media, the effects of physical characteristics was not studied separately. Hence, due to the application of these relations, physical characteristics of porous materials effect must be investigated separately. In various constructed physical models of porous media, the effect of several variables such as ...

The International System of Units (SI) is supposed to be coherent. That is, when a combination of units is replaced by an equivalent unit, there is no additional numerical factor. Here we consider dimensionless units as defined in the SI, e.g. angular units like radians or steradians and counting units like radioactive decays or molecules. We show that an incoherence may arise when different un...

This article is proposed to address the melting heat transfer of a Jeffrey fluid in Blasius and Sakiadis flow caused due to a moving surface. Thermal radiation and a constant free stream are considered in this mathematical model. The non-linear coupled dimensionless equations from the governing equations are attained by employing appropriate similarity transformations. The resulting dimensionle...

In the present approach, a two-dimensional steady MHD free convection flow and mass transfer over a stretching sheet has been analyzed numerically including the Dufour and Soret effects with a magnetic field. The governing differential equations of the problem have been transformed into a system of non-dimensional differential equations, which are then solved numerically using a sixth-order Run...

A dimensional analysis of the momentum balance in circulating fluidized beds reveals that the fluid dynamics of these units is governed by five dimensionless groups. However, it is not possible to match the hydrodynamics of a range of industrial circulating fluidized beds using a single laboratory facility operated at ambient temperature and pressure. To address this difficulty, Glicksman, et a...

Sinusoidal horizontal vibrations have been applied to a parallelepiped containing rounded sand grains. To model the granular medium behavior, a commercial software based on Molecular Dynamics has been used. The influence on the rheologic behavior of many process parameters, such as the dimensionless acceleration and the frequency has been studied. The velocity, density, pressure and mass flow f...