Modelling of heat flow has become a standard practice in many solidification processes. Effort is currently being made to couple heat flow calculations to related macroscopic phenomena such as mould filling, fluid flow, macrosegregation, or thermal stresses. If these macroscopic aspects are important in predicting formation of macroscopic defects or optimising process conditions, then microstructural features such as phase appearance, morphology, grain size, spacings, or microdefects are certainly no less important in determining the ultimate mechanical properties of the solidified product. The aim of the present paper is to introduce the basic concepts of macroscopic and microscopic phenomena which enter normally into any solidification process. At the macroscopic level, i.e. at the scale of the whole process (casting, weldment, … ), the latest developments in numerical techniques which are used to solve the continuity equations are briefly presented together with the advantages and inconvenience...

Modelling of microstructure formation in solidification processes

https://docs.lib.purdue.edu/cgi/viewcontent.cgi?article=1014&context=coolingpubs

Thermally Developing Flow and Heat Transfer in Rectangular Microchannels of Different Aspect Ratios

A State-of-the-Art Review of Gas-Solid Turbulent Fluidization

Modeling forced liquid convection in rectangular microchannels with electrokinetic effects

Publisher Summary This chapter provides an overview of the analytical and experimental hydrodynamics and heat transfer studies of Newtonian and non-Newtonian fluids in laminar and turbulent flow through rectangular tubes. The chapter in particular focuses on the rectangular duct geometry, with emphasis on the friction factor and heat transfer behavior of non-Newtonian fluids. It is recognized that non-Newtonian behavior is generally more complicated than Newtonian flow. In the case of non-Newtonian fluids, the theoretical predictions yield low estimates of the heat transfer under laminar flow conditions. The fact that the available experimental heat transfer measurements lie above the predictions could reflect an inadequacy in the analytical model. For non-Newtonians in turbulent flow through rectangular channels, the situation is even more complicated. Some non-Newtonian fluids act as pseudoplastics, showing some reduction in friction and heat transfer as compared with a Newtonian fluid. Other non-Newtonian fluids experience large reductions in the friction factor and in heat transfer under turbulent flow conditions.

V.M.K. Sastri

Papers

Laminar forced convection heat transfer of a non-newtonian fluid in a square duct

Efficient evaluation of diffuse view factors for radiation

An analysis of the conductive and radiative heat transfer to the walls of fluidized bed combustors

Efficient numerical method for two-dimensional phase change problems

Numerical study of steady laminar fully developed fluid flow and heat transfer in rectangular and elliptical ducts rotating about a parallel axis