Collision cross sections between oxygen molecules and helium atoms are computed at translational energies between 0.1 K and 10.0 K, motivated by the recently demonstrated cooling of molecules by a helium buffer gas. Detailed calculations based on a rigid-rotor model demonstrate the differences among various isotopic combinations of oxygen atoms and also serve to illustrate resonant features uni...

Dynamic interaction between two bodies, where one is significantly more flexible than the other, is common (e.g. rotor-casing contact). This paper presents a linear model for simulating contact between rigid and flexible bodies. The motion between contacts is predicted by modal superposition, using separate models for the two components. During contact, the models are coupled via a linear conta...

High-K isomer decay rates are compared and interpreted, with an emphasis on the spin degree of freedom. It is argued that high-K values do not in themselves lead to K mixing. Rather, evidence is presented that the most important consideration is the isomer energy relative to a rotor whose moment of inertia is approximately 85% of the rigid-body value. The high-spin limit to the occurrence of hi...

A bar-slider framework is a bar-joint framework a part of whose joints are constrained by using line-sliders. Such joints are allowed to move only along the sliders. Streinu and Theran proposed a combinatorial characterization of the infinitesimal rigidity of generic bar-slider frameworks in two dimensional space. In this paper we propose a generalization of their result. In particular, we prov...

in this research, the steady-state flow filed around a 3d body and rotor configuration of the robin helicopter is simulated. the rotor is modeled by an actuator disk. for this purpose, an annular computational domain replaces the rotor and some modeled source terms are added to the momentum equations. this modeling of rotor considerably speed up computational time. the flow field over this heli...

in this research work with the aid of tagouchi experimental design and rawing of interaction curves with minitab software, the best rotor speed and dump temperature of mixing for physico-mechanical and rheological properties of the rubber compound with three mixing steps was obtained. moreover by plotting the mean curves in excel worksheet, the dependency of properties on rotor speed, dump temp...

This paper analyzes some basic design aspects for a three phase diamagnetic levitating rotor. A proposed design uses a triangular configuration of magnets for a levitating rotor. A formula for finding a the approximate levitation point of the rotor is given. The proposed system uses three phase alternating current and a nine coil configuration to drive the levitating rotor. For this configurati...