Simcenter STAR-CCM+ 2406
User Guide
Simcenter STAR-CCM+ can model a wide range of physics phenomena including fluid mechanics, solid mechanics, heat transfer, electromagnetism, and chemical reactions. Scenarios with multiple time scales can be solved within the same simulation.
Heat transfer is the study of energy in transit due to a temperature difference in a medium or between media. Heat transfer extends thermodynamic analysis through the study of the modes of energy transfer and through development of relations to calculate energy transfer rates.
Thermal comfort refers to the level of satisfaction that a human has with the environmental conditions in his or her surroundings. Achieving and maintaining thermal comfort is a key goal of HVAC (Heating, Ventilation, and Air-Conditioning) system design and operation.
Simcenter STAR-CCM+ contains a wide range of physics models and methods for the simulation of single- and multi-phase fluid flow, heat transfer, turbulence, solid stress, dynamic fluid body interaction, aeroacoustics, and related phenomena. These physics models are all selected using a physics continuum.
This section provides information on how to set up physics models in STAR-CCM+.
This part of the documentation describes preparation and procedures for running a Simcenter STAR-CCM+ simulation.
In general, motion can be defined as the change in position of a body with respect to a certain reference frame.
The primary function of the Space models in Simcenter STAR-CCM+ is to provide methods for computing and accessing mesh metrics. Examples of mesh metrics include cell volume and centroid, face area and centroid, cell and face indexes, and skewness angle.
The primary function of the time models in Simcenter STAR-CCM+ is to provide solvers that control the iteration and/or unsteady time-stepping.
Many simulations that involve motion or geometry change require you to move or deform the mesh. Other simulations require localized mesh adaption in order to achieve an accurate solution.
Material models simulate substances, including various mixtures.
Many engineering design projects require you to predict the effect of flowing fluids on containing structures or immersed objects. While you can analyse simple scenarios with hand calculations, complex scenarios require you to apply numerical methods for accurate solutions.
Viscous Flow is a finite element approach for use with viscoelastic materials and other highly viscous non-Newtonian fluids, such as liquid plastics and rubber, dough and similar foodstuffs, molten glass, and mud. Viscoelastic materials resemble elastic materials, but also exhibit viscous effects, rebounding slowly from deformations.
Passive scalars are user-defined variables of arbitrary value, assigned to fluid phases or individual particles. They are passive because they do not affect the physical properties of the simulation. An intuitive way to think of passive scalars is as tracer dye in a fluid, but with numerical values instead of colors, and with no appreciable mass or volume.
Heat conduction is the flow of internal energy from a region of higher temperature to a region of lower temperature by the interaction of the adjacent particles (for example, atoms, molecules, ions, or electrons) in the intervening space. This flow can be viewed as the transfer of energy from the more energetic particles to the less energetic particles of a substance due to interactions between the particles.
Convective heat transfer is the transfer of thermal energy by the movement of a fluid. In engineering practice, it is used to provide specific temperature changes. Examples include heat exchangers, electronic device cooling, and cooling of turbine blades.
Thermal radiation is the emission of electromagnetic waves from all matter that has a temperature greater than absolute zero, and represents a conversion of thermal energy into electromagnetic energy. It is generated by the thermal motion of charged particles in matter, which results in charge-acceleration and dipole oscillation. This drives the electrodynamic generation of coupled electric and magnetic fields, which cause the emission of thermal radiation.
Simcenter STAR-CCM+ solves the governing equation for energy transport within a solid using either the finite volume method or the finite element method.
Simcenter STAR-CCM+ allows you to model the simultaneous, coupled heat transfer between a fluid and an adjoining solid via a solid-fluid interface. The following diagram shows an example application where you calculate the heat transfer between a fluid flowing inside of a solid pipe.
You can model thermal comfort with different levels of complexity. The Equivalent Homogeneous Temperature model quickly provides a local thermal comfort index in the form of the equivalent homogeneous temperature (EHT). The Fiala Thermoregulation model provides more detail in that it incorporates thermophysiological responses of the body and assesses thermal comfort through skin temperature distributions and global thermal comfort metrics.
The Thermal Comfort model makes accessible the following specific thermal comfort models under Optional Models:
The Fiala Thermoregulation models are multi-segment, multi-node models that extensively simulate the human body, including the predictions of overall and local physiological responses. They are based on the average person, with a detailed multi-layered structure of the human body. They model the environmental heat exchange, including local heat losses and gains from the body by free and forced convection, solar irradiation, long-wave radiation, evaporation of moisture from the skin, and insulation effect of the clothing.
The equivalent homogeneous temperature (EHT) is incorporated into the ISO 14505 standard for the evaluation of thermal environments in vehicles or any confined spaces with asymmetric climatic conditions that are close to thermal neutrality. The Equivalent Homogeneous Temperature model uses thermal manikins to represent human bodies, which are subdivided into 17 segments.
The Fiala Thermoregulation models and the Equivalent Homogemeous Temperature model represent the human bodies with manikins.
The manikin geometry part must be sub-divided into 58 part surfaces for the Fiala Thermoregulation models and 17 part surfaces for the Equivalent Homogeneous Temperature model. A convention for naming the individual part surfaces for each of the models can be used to simplify the setup of the thermal network links for the Fiala models and the EHT segments for the Equivalent Homogeneous Temperature model. If you apply the naming convention to the part surfaces of your segmented manikin geometry, the Part Surfaces of the individual network links and EHT segments on the regions level are associated automatically with the corresponding geometry part surfaces.
A network region represents the thermal network for a manikin in a thermal comfort simulation. A thermal network computes the thermo-physiological responses of a human body.
This section discusses the recommendations for accurate use of the Standard Wall Functions and the built-in post-processing heat transfer coefficients.
Boiling is a rapid vaporization of a liquid. It typically takes place when a liquid is heated up to temperatures that exceed the boiling temperature of the liquid.
The Thin Film model provides a simplified approach for simulating deicing or defogging inside a cabin windshield or other surface. It addresses cases where the only features of interest about the ice or fog layer are where the layer is distributed and how thick it is. It assumes that the thickness is negligible compared to cell size.
Heat Exchangers in Simcenter STAR-CCM+ model the heat transfer between two fluid streams—a hot and a cold stream (such as in radiators and air coolers). This section describes how to use the single stream and dual stream heat exchanger options in Simcenter STAR-CCM+.
In mathematics, optimization is the selection of the best element (with respect to some criteria) from a set of available alternatives. In the simplest case, an optimization problem consists of maximizing or minimizing a real function (that is, the objective function) by systematically choosing input values from within an allowed set and computing the value of the function.
This section provides reference information that is common to the energy models in Simcenter STAR-CCM+.
This chapter provides information about the chemical species models in Simcenter STAR-CCM+. A species model is activated whenever a multi-component liquid or multi-component gas is chosen from the Material model section of the Physics Model Selection dialog.
Simcenter STAR-CCM+ allows you to simulate the transport of a fluid or energy (e.g. heat, electrical charge) through porous materials using the concept that the action of the porous media can be represented using appropriate loss (or 'diffusion') coefficients.
The adjoint method is an efficient means to predict the influence of many design parameters and physical inputs on some engineering quantity of interest, that is, on the engineering objective of the simulation. In other words, it provides the sensitivity of the objective (output) with respect to the design variables (input).
Simcenter STAR-CCM+ provides models for axial and radial fans where classical fan laws apply.
The virtual disk model is based upon the principle of representing propellers, turbines, rotors, fans, and so on, as an actuator disk. The actuator disk treatment is practical when you are concerned about the influence of the rotor/propeller behavior on the flow rather than knowing about the detailed interactions between the flow and the blades of the rotating device.
Most fluid flows of engineering interest are characterized by irregularly fluctuating flow quantities.
The term transition refers to the phenomenon of laminar to turbulence transition in boundary layers. A transition model in combination with a turbulence model predicts the onset of transition in a turbulent boundary layer.
Wall distance is a parameter that represents the distance from a cell centroid to the nearest wall face with a non-slip boundary condition. Various physical models require this parameter to account for near-wall effects.
The Radiation Model is the gateway, or entry point to all of the radiation modeling capabilities of Simcenter STAR-CCM+. This section describes Simcenter STAR-CCM+’s radiation modeling.
Aeroacoustics investigates the aerodynamic generation of sound.
Simcenter STAR-CCM+ provides a selection of models that you can use to simulate a wide range of reacting flow applications.
In an internal combustion engine (ICE), for example a gasoline engine, the process of combustion takes place in a cylinder (or cylinders) within the engine. The working fluid is a fuel and oxidizer mixture (usually air), which reacts to form combustion products.
Multiphase flow is a term which refers to the flow and interaction of several phases within the same system where distinct interfaces exist between the phases. Simcenter STAR-CCM+ considers flow options where phases coexist as: gas bubbles in liquid, liquid droplets in gas, and/or solid particles in gas or liquid, and/or (large scale) free surface flows.
Dynamic Fluid Body Interaction (DFBI) in Simcenter STAR-CCM+ allows you to simulate the motion of a 6-DOF body with the displacement and rotation resulting from the defined mechanical and multiphysics interaction (flow, DEM, solid stress, EMAG).
Some unsteady flows have a regularly repeating flow pattern, that is, they are time-periodic. Consider the flow from a fan blade passing across the entrance to a duct. Measurements of the instantaneous flow just within the duct would show a regularly repeating pattern. If the flow disturbances are sufficiently large, and propagate to the end of the duct, measurements of the unsteady flow at any point within the duct show repeating patterns. Such time-periodic patterns can be expressed using Fourier series.
Simcenter STAR-CCM+ allows you to model the response of a solid continuum to applied loads, including mechanical loads and thermal loads that result from changes in the solid temperature.
Simcenter STAR-CCM+ allows you to model engineering applications involving electromagnetic phenomena. Example applications are electric motors, electric switches, and transformers, which can be modeled based on the classical theory of Electromagnetism.
Electrochemistry is the study of chemical reactions which occur due to an imposed electrical charge, or a difference in electrical potential at a boundary between a conductor–such as a metal–and an electrolyte. Simcenter STAR-CCM+ provides models that allow you to simulate batteries, corrosion, etching, and other electrochemical reactions.
Electrical circuits are conducting loops of interconnected electrical components, such as batteries, power sources, resistors, and inductors.
Plasma is a state of matter similar to a gas that is composed partially or completely of charged particles such as ions and electrons which are not bound to each other.
You can simulate batteries in Simcenter STAR-CCM+ using battery cells and battery cycling procedures that are defined either directly in Simcenter STAR-CCM+, or in the external software package Simcenter Battery Design Studio.
Casting simulations are performed using transient multiphase simulations using the VOF model with solidification. Conjugate heat transfer is applied between the solidifying melt and the solid mold.
This section provides some guidelines on how to use region sources for some common problems.
The Cell Quality Remediation model helps you get solutions on a poor-quality mesh. This model identifies poor-quality cells, using a set of predefined criteria, such as Skewness Angle exceeding a certain threshold. Once these cells and their neighbors have been marked, the computed gradients in these cells are modified in such a way as to improve the robustness of the solution.
This part of the documentation provides guidelines on applying Simcenter STAR-CCM+ models to your applications.
In Simcenter STAR-CCM+, solvers compute the solution during the simulation run.
