For establishing an experimental station that carries out mineral prospecting on the Moon and also houses periodic human visits for space-based explorations, a cooling (or thermal management) system is to be designed for the high-powered electronic systems that are needed to operate the controls. One of the most effective methods for large heat flux dissipation is to use phase change, or boiling, as the primary convection mechanism. For designing one such pressurized system, calculate the maximum heat flux attainable in nucleate boiling with saturated water at 200 kPa pressure. Note that the gravitational field on the Moon surface is 1.622 m/s2 , which is approximately a little less than one- sixth that on Earth.
GIVEN
FIND
? The maximum heat flux (q"max)
ASSUMPTIONS
? Steady state conditions
? Nucleate pool boiling
PROPERTIES AND CONSTANTS
From Appendix 2, Table 13, for water at 200 kPa
From Table 9.2, the surface tension (o) = 0.0547 N/m
The maximum heat flux is given by Equation (9.4)
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