Abstract
This paper describes air cooling performance for electronic circuit boards set in the thin enclosure, where cooling air flow pass is very narrowed by many mounted devices. Especially, we focused on the effects of various heat dissipation values from chips and the space on the board. To discuss the cooling performance in the thin enclosure, we designed a test enclosure model which is composed of a model cardboard including 5 heat sources and a narrow heatsink duct and inspected a temperature rise of the model board and heat sources. From the result, it is found that we obtained a similar cooling performance regardless of different heat dissipation values and heat dissipation locations. This is caused by the high thermal conductivity electronic boards and a heatsink on the board to dissipate the heat, even with narrow cooling flow pass on the board. On the other hand, natural convection and radiation from the enclosure also have an important effect to heat release in the high-density packaging device. However, by the effect of forced convection cooling, temperature rise of components is decreased of 20℃ as compared to the result without air flow. Therefore, local forced convection by the narrow duct is effective for the heat release from the high-packaging density device.
