1. Introduction
STAR-CD V4.22 is the latest version of our STAR-CD/es-ice suite, designed to address
outstanding issues arising from previous releases and to add a number of important
enhancements.
2. STAR and pro-STAR
2.1 New developments
1. A stand-alone post-processing utility is available to perform Proper Orthogonal
Decomposition (POD) on variables present in transient post data (.ccmt) files
produced in multi-cycle simulation studies (see STAR-CD User Guide Chapter 19,
“POD analysis of transient post data files”).
2. Activity coefficients may be used to calculate more accurate vapour pressures at the
surface of multicomponent fuel droplets. These are important for mixtures whose
constituents have very different molecular structures, e.g. for so-called E-fuels such
as blends of gasoline and ethanol (see Methodology Chapter 12, “Prediction of
vapour-liquid equilibrium in multicomponent liquids” and the on-line Help text for
pro-STAR panel “Lagrangian Multi-Phase > Droplet Properties”). Liquid films
created from such droplets will also inherit this method of vapour pressure
calculation at the film surfaces (see STAR-CD Methodology Chapter 15 or
STAR-ICE Methodology Chapter 10, topic “Condensation / Evaporation”).
3. A more accurate wall function treatment due to Werner and Wengle has been
introduced for LES turbulence models (see Methodology Chapter 6, “Improved
model”). The pro-STAR GUI also offers a choice of wall functions for use with
LES simulations (see the on-line Help text for pro-STAR panel “Liquids and Gases
> Turbulence Models > Near-Wall Treatment”)
4. A one-dimensional conjugate heat transfer model (1DCHT) was developed to allow
economical calculation of engine in-cylinder wall heat transfer (see Supplementary
Notes Chapter 20)
5. New options for specifying droplet parcel injection conditions are presented in
Supplementary Notes Chapter 21
6. The pro-STAR interface now offers a choice of methods for specifying inflow
boundary conditions for LES turbulence models. The Synthetic Eddy Method
(SEM), implemented via Extended Data in earlier STAR-CD versions, is now
available through the GUI together with an additional divergence-free SEM model
(see Methodology Chapter 6, “Inlet Perturbations in LES Models” and the on-line
Help text for pro-STAR panel “Define Boundary Regions > Inlet > Turbulence
quantities”)
7. pro-STAR allows an unlimited number of droplet types to be defined in a spray