Advanced Boiling Cooling Technology Using a Compact Vessel with a Low Water Level

Abstract

There is a strong demand for compact cooling devices that is used for power electronics such as inverters of electric vehicles. Aiming for improving the performance of cooling devices with downsizing it, boiling heat transfer attracts a lot of attention because of its high heat transfer coefficient. However, there is few reports related to subcooled pool boiling using a compact vessel. In this study, to achieve a higher heat flux removing using a compact vessel, subcooled pool boiling was investigated by varying a water level, as well as microbubble emission boiling characteristics. As a result, the experimental result found that the onset of microbubble emission boiling is affected by the water level. Fig. 1 Boiling curves with or without microbubble emission boiling (MEB).130Next, boiling curve was investigated by varying the water level, as shown in fig. 6. Ivey and Morris correlation [18] at the 131 liquid subcooling of 35 K, which can predict CHF value in subcooled pool boiling, is also plotted with a solid line. The chained 132 lines show the same correlations at the liquid subcooling of 25 K and 45 K. As noted above, the degree of liquid subcooling 133 was temporary decreased to less than 20 K at 400 W/cm 2 with 8 mm because of a large fluctuation in liquid subcooling 134 (13 K at a maximum). Therefore, Ivey and Morris correlations were calculated at the degree of liquid subcooling of 135 35 K ± 10K. As a result, the CHF values were approximately corresponded to Ivey-Morris correlations. In this study, 136 when water level is higher than 10 mm, it was possible to keep the average degree of liquid subcooling at 35 K at 400 137 W/cm 2 . In contrast, the average degree of liquid subcooling was decreased to 33 K when water level is lower than 8 mm at 138 400 W/cm 2 . Moreover, MEB was not maintained and film boiling was observed at water level of 6 mm. Consequently, the 139 experimental result found that it is required to optimize the design of heat exchanger for keeping the degree of liquid subcooling 140

Visualization and Sound Measurements of Vibration Plate in a Boiling Bubble Resonator

“…When the BBR was not installed (i.e., during normal boiling heat transfer), the CHF was 3.6 MW/m 2 . Thereafter, microbubble emission boiling occurred, which is well known behavior at subcooled pool boiling [12]. The boiling curve corresponding to the setup with the BBR was totally different from that corresponding to the setup without the BBR.…”

Lattice Boltzmann Simulation of Ferrofluids Film Boiling

“…Various examinations have demonstrated that the grid Boltzmann technique is successful in contemplating the convection heat move under different field powers. References [16][17][18][19][20][21][22][23][24][25][26][27][28][29] in constrained convection, results uncovered that temperature inclination decreases with the ascent of Rayleigh number. In normal convection, the normal Nusselt number increments with the expansion of Rayleigh number and the lessening of Hartmann number.…”