The critical heat flux (CHF) is a thermal limit at which a boiling crisis occurs whereby an abrupt rise in temperature causes overheating on fuel rod surface that leads to damage. A cylindrical fuel rod of 2 cm in diameter is encased in a concentric tube and cooled by water. The fuel generates heat uniformly at a rate of 150 MW/m³. The average temperature of the cooling water, sufficiently far from the fuel rod, is 80°C. The operating pressure of the cooling water is such that the surface temperature of the fuel rod must be kept below 300°C to avoid the cooling water from reaching the critical heat flux. Determine the necessary convection heat transfer coefficient to avoid the critical heat flux from occurring.

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T, egen = 150 MW/m³ Cooling water, 80°C Fuel rod IT D = 2 cm