`==Example heat exchanger Data== Heater, Annular-Gap Heat-exchanger {| class=``wikitable`` |- ! Dimension ! Inches ! cm ! mm ! m |- |Inner diameter of pipe  |4.920 |12.5  |125.0  |0.125 |- |Perimeter  |15.450  |39.2  |392.4  |0.392 |- |Length of gap (same as length of tubular heater) | 11.191  |28.4  |284  |0.284 |- |Gap Depth (thickness) (=Aff/perimeter)  |0.050  |0.13  |1.3  |0.001 |- |Hydraulic Radius  |0.025  |0.06  |0.6  |0.001 |- |Total outer HX-area (linear units^2) | 192  |1238  |123811 |0.124 |}               Cooler, Slot Heat-exchanger {| class=``wikitable`` |- ! Dimension ! Inches ! cm ! mm ! m |- |Inner diameter of pipe  | 5.174  | 13.1   | 131.4   | 0.131 |- |Minimum Required pipe diameter   | 5.17  |   |  |    |- |Minimum Required Pipe wall thickness  | 0.303  |  0.769  | 7.69 |  0.007689 |- |Length of heat exchanger  | 3.392 |  8.616  |  86.2  |  0.086157 |- |Hydraulic Radius of slots  | 0.013 |  0.033  |  0.326  |  0.000326 |- |Width of slots (min = kerf)  | 0.030  |  0.1  |  0.76 |  0.000762 |- |Slot Depth (or fin height)      | 0.178 |  0.5  |  4.5  |  0.005 |- |# of slots   (# of slot & fin pairs)  | 361 |  361 |  361  |  361 |- |Width of fins (material between slots)   | 0.015 |  0.04 |  0.38  |  0.000381 |- |Total wetted-area (linear units^2)   | 490  |  3163  |  316317  |  0.316 |}`