Here is the abstract you requested from the Thermal_2014 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Using CFD for Modeling Enclosures – A Comparison of Exact vs Abstract Geometries|
|Keywords: Modeling, Simulation, CFD|
|Product designs today are created in CAD systems with precise and full geometry of all the parts used in the product. However, many thermal analysis methods use simpler geometry, especially for the cuboid or block type designs used in electronics boxes and enclosures. One relevant question is whether one can represent geometry that is not block-shaped well enough with the traditional cuboid-type analysis software, and what are the key elements in doing so. To answer this, a cylindrical LED traffic signal model was modeled in two different CFD systems and cooled using natural convection and radiation. The key parameter used for similarity is the dissipative surface areas of the signal rather than other ones such as characteristic lengths. Solving the models showed that the temperatures of key components are less than 2°C apart for system component temperatures of 40°C above ambient conditions. While the geometries are quite different, this shows the concept of area similarity is possible for some if not many electronic thermal analysis problems. Given that the solution method for the cuboid-type CFD solvers is often faster, this method would allow engineers to iterate designs more quickly before solving the problem in a more geometrically accurate CFD model, if desired.|
|James Petroski, Mechanical Application Engineer