An airstream of speed 160 m/s and temperature 3000 K travels on the inside of a 30 cm I.D. steel tube whose wall thickness is 2.5 mm. On the outside of the tube, water coolant flows coaxially in an annular space 6.1 mm thick. The coolant velocity is 10 m/s, and it has a local temperature of 15°C. Both flows are approximately fully developed. The pressure of the airstream is around 140 kPa. Estimate the maximum wall temperature of the tube.

A liquid is entering a 10 m long pipe of 0.2 m diameter at 25°C with an average velocity of 0.02 m/s. The pipe is kept at a constant surface temperature of 40°C. Assume the flow is both hydrodynamically and thermally fully-developed in the pipe. Find out the outlet temperature. Justify if the assumption of fully-developed flow is appropriate. The properties of the fluid can be assumed constant with following values Density: 484.2 kg/m³; Specific heat capacity: 2802 J/kg.K; Thermal conductivity: 0.0904 W/m.K; Dynamic viscosity: 9.197 × 10-5 kg/m.s; Prandtl number: 2.85. 29.3 °C

In the final stages of production, a pharmaceutical is sterilized by heating it from 25 to 75°C as it moves at 0.21 m/s through a straight thin-walled stainless steel tube of 12.7-mm diameter. A uniform heat flux is maintained by an electric resistance heater wrapped around the outer surface of the tube. If the tube is 10 m long, what is the required heat flux? If fluid enters the tube with a fully developed velocity profile and a uniform temperature profile, what is the surface temperature at the tube exit? Fluid properties may be approximated as p = 1000 kg/m³, c, = 4000 J/kg-K, µ = 2x 103 kg/s-m, k = 0.8 W/m-K, and Pr = 10. Determine the required heat flux, W/m². q! = i W/m? Determine the surface temperature at the tube exit, in °C. i °C S,0

You are designing a pin-style heatsink for forced cooling of an IC. A small fan blows RT air into the heatsink at about 2.3 ? ? . The aluminum pins are 2mm in diameter and have a constant surface temperature of 120°?. The heatsink is 100mm x 100mm and the pins have an inline arrangement with a transverse pitch of 4mm and a longitudinal pitch of 6mm. What is the total heat dissipation of this heatsink? The pins are 30mm high. Note RT=25 celsius