In the May 2006 issue the Calculation Corner focused on the comparison of liquid coolants using the Mouromtseff number [1]. For single phase forced convection, Mouromtseff found this figure of merit, Mo, to follow the form where ρ, k, cp, and � represent the density, thermal conductivity, specific heat (at constant pressure) and dynamic viscosity of the fluid. The … [Read more...]
High Powered Chip Cooling — Air and Beyond
Introduction Over the past few years many people in the electronics industry have become concerned with the increases in heat density at both the chip and module level of packaging. This trend is not new and has been with us since the days of bipolar chips. As can be seen in Figure 1, the heat flux associated with bipolar circuit technologies steadily increased from the … [Read more...]
The Challenge of Operating Computers at Ultra-low Temperatures
Although the potential for low temperature enhancement of CMOS circuit performance has been recognized for some time, circuit scaling (proportionally reducing the size of the circuit) has been the preferred method of achieving higher performance. But as minimum feature size passed well into the sub-micron and now into the nanometer region, this route to higher performance has … [Read more...]
