Patent ID: 7059396

Claim:
A micro channel heat exchanger for gaseous fluids, in which the micro channels have a surface area density greater than 10000 m 2 /m 3 and a constant volume, the micro channels in the heat exchanger having an aspect ratio selected a priori by: determining the thermal performance of the heat exchanger to obtain data with regard to a channel corresponding to heat transfer rate, velocity and flow; plotting the performance curves of 1) pressure loss in the channel for the hot side; 2) pressure loss in the channel for the cold side; 3) heat flux; and 4) heat transfer rate against an axis corresponding to aspect ratio; determining a range of aspect ratios based on the curves plotted in which the points on the aspect ratio axis corresponding to the intersections of the maximum and minimum of the gradients of the heat flux and heat transfer curves define the range and selecting an aspect ratio for the micro channel from the range of aspect ratios determined.