Designer fluid performance and inclination angle effects in a flat grooved heat pipe

Effect of design and operating parameters on the thermal performance of aluminum flat grooved heat pipes

“…Porous structure, screen mesh, non-circular micro-channels with sharp-angled corners and axial grooves are some examples of wick structures, which enable the heat pipes to function even against or in the absence of gravity [5]. For the case of grooved wick structures, various groove geometries have been studied in the literature such as fan-shaped [6], circular [7], reentrant [8,9] triangular [9,10], trapezoidal [7][8][9][11][12][13] and rectangular [7][8][9]12,[14][15][16][17][18][19][20][21][22][23][24][25][26][27] cross-sections. Particularly, heat pipes with rectangular grooves can be easily modeled and/or numerically studied due to the simplicity of the groove geometry [28,29].…”

“…Particularly, heat pipes with rectangular grooves can be easily modeled and/or numerically studied due to the simplicity of the groove geometry [28,29]. Thermal performance of a heat pipe can be influenced by a variety of factors such as wall material, wick structure [30][31][32], working fluid [18] and its charge amount [6,22,23,33], input heat load, and inclination angle [24,34].…”

“…Flat plate, or simply, flat heat pipes have been investigated in many studies due to the ease of manufacturing and experimentation. Due to its superior thermal conductivity and compatibility with various working fluids, copper has been typically selected as the base material for heat pipes, and has been at the focus of many studies in the literature [12,[22][23][24]. In a pioneering study, Hopkins et al [12] compared the maximum heat transfer capability of flat heat pipes with rectangular and trapezoidal groove geometries.…”

“…Moreover, a very small or very high vapor space thickness results in trapping of the working fluid in the corners and sides of the heat pipe or dominating the gravitational forces and flooding the grooves, both adversely affecting the performance of the heat pipe. Thermal performance of a copper flat grooved heat pipe with axial rectangular grooves charged with different concentrations of a designer fluid was experimentally studied for different inclination angles [24]. Compared to water, a chemically advanced working fluid demonstrated a better performance by lowering the thermal resistance of the heat pipe by approximately 20% and extending the onset of dryout to higher heat loads.…”

Experimental Thermal Performance Characterization of Flat Grooved Heat Pipes

“…Various groove geometries have been studied, such as fan-shaped [7], circular [8], trapezoidal [8], [9], [11], and [12], triangular [13] and rectangular [8], [11], [14]- [22] cross-sections. Copper [7], [10], [11], [13]- [18], [22] and aluminum [9], [20], and [21] were the most common base materials used in the experimental studies. In addition to water, acetone, methanol, and n-pentane, which are all compatible with copper, some special solutions [22] and nano-fluids [16], [17] have been used in previous studies to investigate the effect of the working fluid on the thermal performance of copper heat pipes.…”