We consider a time-dependent random field, f(rZt), defined on a spherical shell [Q=(6,q), O56 , -t<(p it] or cylindrical annulus [92=P, -1E<(P57r]. Examples are the temperature distribution, T(r,2,t), or the radial component of the flow velocity, u(r,2,t), obtained from numerical simulations of high Rayleigh number convection. For such a field the spatio-temporal two-point correlation function,...

This work presents characterization data and viscosity of 34 secondary vacuum gas oils (H-Oil oils, visbreaker fluid catalytic cracking slurry oils) with aromatic content reaching up to 100 wt.%. Inter-criteria analysis was employed define the VGO characteristic parameters which have an effect on viscosity. Seven published empirical models predict were examined for their prediction ability. The...

Biodiesel is a promising non-toxic and biodegradable alternative fuel used in the transport sector. Nevertheless, the higher viscosity and density of biodiesel poses some acute problems when it is used it in unmodified engine. Taking this into consideration, this study has been focused towards two objectives. The first objective is to identify the effect of temperature on density and viscosity ...