Deformation of the material during cyclic expansion extrusion (CEE) is investigated using upper-bound theorem. The analytical approximation of forming loads agrees very well with the FEM results for different amounts of chamber diameter, friction factor and also for lower die angles. However, the difference between analytical and numerical solution increases at higher die angles which are expla...

Waste fibers produced from manufacturing processes are a byproduct commonly deposited in storing yards and/or landfills and thus results in many serious environmental problems in Iran. If these waste materials could be advantageously put to practical use in any application, it would reduce the burden on the environment and landfills. This paper compares the performance of the stone matrix aspha...

in the present study, turbulent flow in channels of a plate heat exchanger with corrugated chevron plates has been simulated numerically using the commercial cfd package, fluent. unstructured mesh is used for discretizing the computational domain and simple algorithm is utilized to solve the pressure and velocity equations. there is a wide selection of different plate heat exchangers within the...

physical and mechanical properties of alfalfa (medicago sativa, l.) grind are required for optimum design of equipment used in transporting, processing and storage of the material. this study was conducted to determine the effect of particle size (2.38, 3.36 and 4.76 mm) and moisture content (8, 9.3 and 11% wb) on some physical and mechanical properties of alfalfa grind. these properties includ...

Friction at the nanoscale has revealed a wealth of behaviours that depart strongly from the long-standing macroscopic laws of Amontons-Coulomb. Here, by using a 'Christmas cracker'-type of system in which a multiwalled nanotube is torn apart between a quartz-tuning-fork-based atomic force microscope (TF-AFM) and a nanomanipulator, we compare the mechanical response of multiwalled carbon nanotub...

stabilization of river terraces and natural soil slopes in rangelands by means of tree roots as a reinforcement agent is an environmental adopted method which needs to be developed. in this research a series of tests was carried out on soil blocks containing willow roots and without roots using a large scale in situ direct shear test apparatus. the results were analyzed based on direct shear th...

We utilize classical molecular dynamics to study the effects of intrinsic, interlayer friction between graphene monolayers, as well as extrinsic attachment or clamping strength between graphene and a model silicon substrate on the energy dissipation Q-factors of oscillating graphene nanoresonators. Both interlayer friction and attachment effects are found to significantly degrade the graphene Q...