Understanding the Hemicube Rendering calculation method

The Hemicube Rendering calculation method option in the Radiation dialog box uses your computer's graphics rendering capabilities to calculate shadowed view factors quickly and accurately.

On your computer, two options are available for hemicube rendering:

• For serial runs, the graphics processing unit (GPU) option is typically faster than the CPU option.

• For parallel runs, the CPU option is typically faster than the GPU option because the parallel processes compete for the same GPU resources.

The actual performance results depend on your computer’s hardware.

Hemicube rendering on Windows

On Windows, the thermal solver performs the hemicube rendering using the CPU by default. You can only use this option if your computer's graphics supports the Open Graphics Library (OpenGL) standard, OpenGL version 2.1 or higher. Make sure that the graphic display color depth is set to 24 bit (“True Color”) or higher.

You can also activate the GPU to take advantage of GPU hardware acceleration. To activate GPU processing, create the Advanced Controls simulation object with a Generic Entity type of INPF Card entity type and specify the following:

• Card Number = 9

• Text Input = GPARAM 56 28 -1

Hemicube rendering on Linux

On Linux, the thermal solver performs the hemicube rendering using the GPU by default. This requires your computer to have an active graphics display and an X session.

Hemicube rendering with OSMesa

Both on Windows and Linux, the thermal solver can perform the hemicube rendering method using the CPU via the OSMesa API of the Mesa 3D Graphics Library. This option does not have any dependencies on the presence of a graphic card or graphics libraries on the Windows machine, or an active graphics display or an X session on the Linux machine. It is better suited for Linux clusters.

To activate CPU processing, do one of the following:

• Set the TMG_HEMI_OSMESA environment variable to ON. You must restart the software before solving your model.

• Create the Advanced Controls simulation object with a Generic Entity type of INPF Card entity type and specify the following:Card Number = 9****Text Input = GPARAM 0 47 1

Hemicube rendering settings

If you select the Hemicube Rendering calculation method option, you can use the Element Subdivision menu to set the granularity of the element subdivision for computing shadowed view factors. Select one of five levels of granularity numbered 0 to 5. A higher subdivision level yields more accurate radiative conductances at the cost of additional computation time. If you select Based on Error Criterion, the thermal solver dynamically estimates a subdivision level for each view factor, using the lowest subdivision level that satisfies the specified view factor error tolerance.

How do I

Define Radiation

Learn more

Radiation types

Understanding enclosures

Understanding view factors

Example 1 - Using the All Radiation type

Example 2 - Using multiple Enclosure Radiation type objects

Understanding the Monte Carlo calculation method

Monte Carlo Settings

Inputs to expressions

Look up more details

Auto-generated expressions

Quick links

Simcenter 3D Thermal/Flow, Electronic Systems Cooling, and Space Systems Thermal boundary conditions

Thermal/Flow, Electronic Systems Cooling, and Space Systems Thermal

Command reference

Pre/Post video examples

Bulk Entry Descriptions

Simcenter 3D tutorials

Browse Simcenter 3D help by product area

Understanding the Hemicube Rendering calculation method, Simcenter 3D 2021.1 Series

© 2020 Siemens

window.mainLanguage="en_US"

window.delivId=""

window.projectId=""

MathJax.Hub.Config({ TeX: { extensions: ["autoload-all.js"] }, tex2jax: { displayMath: [ ] }, "SVG": { scale: 125 } });