ABSTRACT

This chapter is concerned with the development of a simple model that we can apply to non fancooled enclosures. In the first section our derived result will give us the equivalent of the fan curve, i.e., the driving “force” that results in air being sucked into the ventilation inlet and out the ventilation exit. The next step is matching the buoyancy driver to the enclosure head loss, a procedure not unlike what we learned to use with fan-cooled systems. We will use the head loss formulae that are listed in Chapter 3. This chapter ends with a short discussion on how we will later apply the buoyancy principles to an electronics enclosure that is cooled by natural convection, radiation, and of course the internal airdraft. Thus our study of air movement ends, other than for some side issues in the Appendix. We will begin our study of heat transfer in Chapter 6.