RT Journal Article ID 3d75b37239e325c6 A1 Gao, M. A1 Cao, Yiding A1 Beam, Jerry E. A1 Donovan, B. T1 Structural Optimization of Axially Grooved Flat Miniature Heat Pipes JF Journal of Enhanced Heat Transfer JO JEH(T) YR 2000 FD 2000-12-01 VO 7 IS 6 SP 361 OP 369 AB Optimization of flat miniature heat pipes was carried out based on the existing and newly obtained experimental results and the quasi-Newton algorithms employing the BFGS (Broyden, Flether, Golfarb, Shanno) method. The heat pipe contains capillary axial grooves that were cut using the method of electric-discharge-machining (EDM). The general multivariable optimization methods were used to search for the optimum structure of the heat pipe. Based on the optimization results, a miniature copper-water heat pipe with external overall dimensions of 7 × 3 × 120 mm was fabricated and tested. Maximum heat transfer rates of 50 watts in the horizontal orientation and 70 watts in the vertical orientation at a working temperature of 100°C were achieved. The corresponding heat fluxes were 25 and 35 W/cm2, respectively, based on the external heating surface area. These two values are increased to 40 and 56 W/cm2 if the calculation is based on the dimensions of the vapor space. The heat transport capacity of the optimized heat pipe was increased by 66% to 100% at the working temperature of 100°C, compared to the non-optimized heat pipes. The effective thermal conductance of the heat pipe was 60 to 110 times that of a copper bar having the same overall dimensions. PB Begell House LK https://www.dl.begellhouse.com/journals/4c8f5faa331b09ea,15d6757534f5a615,3d75b37239e325c6.html