Steel (AISI 1010) plates of thickness
For an initial plate temperature of
Want to see the full answer?
Check out a sample textbook solutionChapter 7 Solutions
Fundamentals of Heat and Mass Transfer
- Forced air at T0 = 25°C and V = 17 m/s is used to cool electronic elements on a circuit board. One such element is a chip, 4 mm x 4 mm, located 129 mm from the leading edge of the board. Experiments have revealed that flow over the board is disturbed by the elements and that convection heat transfer is correlated by an expression of the form Nuz = 0.04RE0.85 Pr3 V, T. Chip Board L mm Estimate the surface temperature of the chip if it is dissipating 38 mW.arrow_forwardQ1/ Consider the following fluids, each with a velocity of u = 9 m/s and a temperature of 10°C, in cross flow over a 10-mm diameter cylinder maintained at 50°C. Calculate the rate of heat transfer per unit length for saturated water? ***** 2 Satu Dety PP Liquid 3149 9920 4.246 996.0 528 9040 7.354 902.1 393 9901 Nu 0.3+1 Endalay Specific Heal Veputation 0.62 Re2 Pro [1 + (0.4/Pypa[1+ (282,000) aper 0.0231 2402 4180 00304 4378 0.0397 2419 4178 0.0612 2407 4179 00655 2335 4180 tree Thermal Coductivity THAY Liquid Vapor Le Dynamic Vacosity 1870 Vapor Liquid 0607 0.0186 0110 0.90710 1875 0615 0.0169 0.796 101 100110 1880 BAZ3 0.0192 0720x10 1016 10 1825 0.631 0.5196 0653x10 103150 1832 0437 0.0000 0596x10104610 Fran www. Lignon A'IN Ligad Vaper 614 1.00 0.24710 542 100 0234-10 4.83 1.00 0.337x10 4.32 100 0377x10 191 100 0415-10arrow_forwardQ2/ cylindrical electrical heating element (dissipated 1000 W/m) of diameter D=10 mm, thermal conductivity k=240 W/m K, density 2700 kg/m3, and specific heat cp = 900 J/kg K is installed in a duct for which air moves in cross flow over the heater at a temperature and velocity of 27°C and 10 m/s, respectively. calculate the surface temperature per unit length of the heater.arrow_forward
- Required information Water at 20°C is flowing with velocity of 0.89 m/s between two parallel flat plates placed 1 cm apart. Given: The properties of water at 20°C are p= 998.0 kg/m3, µ = 1.002 x 103 kg/m-s and Pr = 7.01 Determine/the distance from the entrance at which the velocity boundary layers meet. (Round the final answer to one decimal place.) The distance from the entrance at which the velocity boundary layers meet is m.arrow_forwardSteel (AISI 1010) plates of thickness δ = 8 mm and length L = 1.3 m on a side are conveyed from a heat treatment process and are concurrently cooled by atmospheric air of velocity u∞ = 11 m/s and T∞ = 23°C in parallel flow over the plates. For an initial plate temperature of Ti = 329°C, what is the rate of heat transfer from the plate? What is the corresponding rate of change of the plate temperature? The velocity of the air is much larger than that of the plate.arrow_forwardHeat transfers Air at temperature 20 C and pressure 1 atm, flow over a flat plate at 3 m/s. The surface temperature of the plate 60 C and the plate width 30 cm, at distance 30 cm from the leading edge .Take the air properties as following, µ=2.02x10^-5 kg/m.s, k=0.0292 W/m.C, Cp=1.01 kJ/kg.C, : ρ = 1.128 kg/ m3, Pr=0.7. Choose the correct answer:arrow_forward
- Consider two cases involving parallel flow of dry air at V = 1.5 m/s, T=45°C, and atmospheric pressure over an isothermal plate at T = 20°C. In the first case, Rex, = 5 x 105, while in the second case the flow is tripped to a turbulent state at x = 0 m. At what x -location, in m, are the thermal boundary layer thicknesses of the two cases equal? What are the local heat fluxes, in W/m², at this location for the two cases? x = 9jam 9 turb II = i i m W/m² W/m²arrow_forwardSteel (AISI 1010) plates of thickness 6 = 6 mm and length L = 1 m on a side are conveyed from a heat treatment process and are concurrently cooled by atmospheric air of velocity u, = 10 m/s and Tg = 30°C in parallel flow over the plates. -Conveyor Air T For an initial plate temperature of T; = 310°C, what is the rate of heat transfer from the plate? What is the corresponding rate of change of the plate temperature? The velocity of the air is much larger than that of the plate.arrow_forwardAir at 20 ◦ C flows inside a pipe 18-mm-ID having a uniform heat flux of 150 W/m 2 on the surface, the average flow velocity at entry being 1.0 m/s. The air pressure is 2 bar. Determine the value of convection coefficient. If the pipe is 2.5 m long, determine the air exit temperature and the wall temperature at the exit. Assume fully developed hydrodynamic boundary layer.arrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning