The role of dissolved carbon dioxide in case of high mass flux spray quenching, dropwise and flow boiling on a hot steel plate.

In the current work, by altering the vapour bubble formation and their coalescence rate, the Leidenfrost effect is tried to eliminate or minimize by dissolving carbon dioxide in the water spray. The heat transfer analysis indicates that the heat removal rate steps up with the increment in carbon dioxide concentration up to 8 gm/litre soda concentration in water and a further rise in carbon dioxide concentration, quenching rate declines. The droplet impact mapping and the film boiling analysis corroborate the aforesaid results. The evaporation experiment also supports above findings and indicates unalteration of boiling point. The spray cooling result shows 37% enhancement in critical heat flux (CHF from 1.2 MW/m2 to 1.67 MW/m2) at 8 gm/litre soda concentration in water. The comparison of the critical heat flux with the results reported in the literature clearly asserts the suitability of the current methodology for the fast cooling operation. • Heat flux increases with rise in soda concentration up to 8 gm/litre in water. • The highest CHF of 1.67 MW/m2 is obtained in case of 8 gm/litre soda concentration in water. • The droplet impact mapping regime corroborates the finding obtained in case of spray cooling. • The comparison confirms the appropriatness of the current process for fast quenching. [ABSTRACT FROM AUTHOR]