abstract increased knowledge of russian knapweed biology would facilitate development of an optimum control program. to examine germination characteristic of this weed, several experiments were conducted in weed research department, plant pest and diseases research institute of tehran during 2003. first experiment was a factorial with 3 replications to break seed dormancy of this weed. first fa...

An investigation of the orientation and temperature dependence of domain wall properties in FeP! is presented. We use a microscopic, atomic model for the magnetic interactions within an effective, classical spin Hamiltonian constructed on the basis of spin density functional theory. We find a significant dependence of the domain wall width and the domain wall energy on the orientation of the wa...

Investigation to evaluate axial wall heat conduction has been conducted for heat transfer in a laminar flow circular tube with two classical thermal boundary conditions at the outside wall. The tube ends are either adiabatic or with heat losses. The simulation is three-dimensional with various wall materials, wall thicknesses and tube lengths. A wide range of Peclet number from 7 to 14,000 is c...

the galerkin finite element method is used to solve the three dimensional continuity, momentum and energy equations for laminar newtonian and power-law model non-newtonian flow through horizontal circular tube. the governing equations are non-dimensionalized with respect to specific variables and converted into algebraic equations using appropriate elements. to accelerate convergence a combinat...

Amagnetohydrodynamic flow of a viscous, incompressible and slightly conducting fluid is developed between a parallel flat wall and a wavy wall whereas at the same time fluid is continuously sucked through the flat wall with a constant suction velocity. The velocity and temperature distribution are determined alongwith the pressure gradient and co-efficient of skin friction.

Condensation of a spherically symmetric submicrometer size vapor bubble is studied using diffuse interface hydrodynamic model supplemented by the van der Waals equation of state with parameters characteristic for argon. The bubble, surrounded by liquid, is held in a container of constant volume with temperature of the wall kept fixed. The condensation is triggered by a sudden rise of the wall t...

Laminar mixed convection of Aluminium oxide (Al2O3)–water nanofluid flow in an inclined annulus using a single-phase approach was numerically studied. Constant heat flux boundary conditions were applied on the inner and outer walls. All the thermophysical properties of nanofluid, such as, viscosity, heat capacity, thermal conductivity, and thermal expansion coefficient...

longitudinal heat conduction is an important parameter in the cryogenic field, especially in cryogenic heat exchangers. in the present work, the parasitic effect of tube wall longitudinal heat conduction on temperature measurement has been studied in cryogenic laminar hydrogen flow. the effects of various parameters such as wall cold end temperature, wall thermal conductivity, gas volumetric fl...

Laminar mixed convection of Aluminium oxide (Al2O3)–water nanofluid flow in an inclined annulus using a single-phase approach was numerically studied. Constant heat flux boundary conditions were applied on the inner and outer walls. All the thermophysical properties of nanofluid, such as, viscosity, heat capacity, thermal conductivity, and thermal expansion coefficient, except density in the bo...