The onset of turbulence in a gas flowing within a cir- cular tube occurs at ReD,c = 2300, while a transition from incompressible to compressible flow occurs at a critical Mach number of Mac = 0.3. Determine the critical tube diameter Dc, below which incompressible turbulent flow and heat transfer cannot exist for (i) air, (ii) CO2, (iii) He. Evaluate properties at atmospheric pressure and a temperature of T = 300 K. flow rate of m· 1 = 10-4 kg/s per channel, determine the outlet temperature and the chip power dissipa- tion for the dielectric liquid. (b) Consider the foregoing conditions, but with air at a flow rate of m· 1 = 10-6 kg/s used as the coolant. Using properties of cp = 1007 J/kg · K, k = 0.0263 W/m · K, and µ, = 185 X 10-7 N · s/m2, determine the air outlet temperature and the chip power dissipation.