Recently, tape wound cores due to their excellent magnetic properties, are widely used in different types of transformers. Performance prediction of these transformers needs an accurate model with ability to determine flux distribution within the core and magnetic loss. Spiral structure of tape wound cores affects the flux distribution and always cause complication of analysis. In this paper, a...

An optimal design strategy for spiral-wound membrane networks based on an approximate permeator model and a mixedinteger nonlinear programming (MINLP) solution strategy is proposed. A general permeator system superstructure is used to embed a very large number of possible network con®gurations. The superstructure allows the development of a MINLP design strategy which simultaneously optimizes t...

CFD simulations have been used to determine mass transfer coefficients and power consumption of commercial net spacers. The simulations show transversal and longitudinal vortices, vortex shedding and instationary flow behavior leading to the enhanced mass transfer in spacer filled-channels compared to empty channels. The results of the simulations were validated with experiments and compared wi...

Two multicomponent models for spiral-wound gas permeators are proposed. The basic transport model is derived from fundamental material balances and permeation relations that account for permeate-side pressure variations. The resulting model consists of a set of nonlinear differential-algebraic-integral equations with mixed boundary conditions, as well as an implicit expression for the local fee...

We present a new method for estimating the corotation radius in tightly wound spiral galaxies, through analysis of the radial variation of the offset between arms traced by the potential (P-arms) and those traced by dust (D-arms). We have verified the predictions of semi-analytical theory through hydrodynamical simulations and have examined the uniqueness of the galactic parameters that can be ...