Abstract
The use of computational fluid dynamics/heat transfer (CFD/HT) software has become common in exploring the thermal and hydrodynamic behavior of many electronic products. Well-designed CFD/HT models are very valuable for driving the product design, but accurate models can be difficult to develop in some cases for a practical use. Manufacturing Resources International (MRI) uses CFD/HT modeling to predict the display limitations of outdoor digital displays under various hazardous environmental conditions. Both the surrounding ambient temperature and solar irradiance are the major contributors to temperature rise inside outdoor digital displays, but most CFD/HT software packages are limited in simulating solar irradiance through semi-transparent materials and multiple surfaces. Therefore, the contribution from solar irradiance must be treated with care when creating a CFD/HT model especially when an optimum number of mesh elements is to be used to minimize the necessary processing power and solution computation time. In the current study, we employ true solar testing to determine how much solar irradiance passes through the vandal glass assembly. In lieu of defining the solar irradiance as a heat flux, a methodology to determine the power that should be imposed on the sun-exposed vandal glass is described. As outdoor digital displays face harsher thermal challenges compared to the displays that are deployed indoors, it is necessary to come up with a display design that can best benefit from the cooling effect. There are numerous parameters that can be adjusted to optimize the display in terms of its thermal performance but in particular, this paper explores the effect of adjusting the gap distance between the vandal glass and the liquid crystal display (LCD) to see how the maximum LCD temperature and fan performance are influenced.
