Steaks (2 cm thick, k = 0.45 W/m - °C, « = 0.91 x 107 m2/s) usually have an original temperature of 25 °C. They will be cooled in a refrigeration room. The said room has a temperature of -11 °C. The heat transfer coefficient on both sides of the steak is 9 W/m2 - °C. How long will it take for both surfaces of the meat to be cooled to 2 °C? Assume the geometry of steaks to be a flat slab.

Steaks (2 cm thick, k = 0.45 W/m - °C, « = 0.91 x 107 m2/s) usually have an original temperature of 25 °C. They will be cooled in a refrigeration room. The said room has a temperature of -11 °C. The heat transfer coefficient on both sides of the steak is 9 W/m2 - °C. How long will it take for both surfaces of the meat to be cooled to 2 °C? Assume the geometry of steaks to be a flat slab.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.10P: 3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the...

See similar textbooks

Similar questions

3.16 A large, 2.54-cm.-thick copper plate is placed between two air streams. The heat transfer coefficient on one side is and on the other side is . If the temperature of both streams is suddenly changed from 38°C to 93°C, determine how long it takes for the copper plate to reach a temperature of 82°C.
3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the atmosphere from outer space. If its original temperature is 38°C, the effective average temperature of the atmosphere is 1093°C, and the effective heat transfer coefficient is , estimate the temperature of the shell after reentry, assuming the time of reentry is 10 min and the interior of the shell is evacuated.
A mild-steel cylindrical billet 25 cm in diameter is to be raised to a minimum temperature of 760C by passing it through a 6-m long strip-type furnace. If the furnace gases are at 1538C and the overall heat transfer coefficient on the outside of the billet is 68W/m2K, determine the maximum speed at which a continuous billet entering at 204C can travel through the furnace.
4.) A 15-cm-diameter steam line carries saturated steam at 6 MPa and is located in a tunnel with stagnant air with a temperature of 50oC. The outside unit convective coefficient is 8.5 W/m2-K. The steam line is covered with 3 cm of 85% magnesia insulation. It is decided to reduce the heat loss by one-half. How much 85% magnesia insulation is required? Neglect thermal resistance of pipe and inside surface.
The flow of water entering a pipe is 0.25 kg / s and its temperature is 20 ° C. The diameter of the pipe is 20 mm and the wall temperature of the pipe is 100 ° C. If the average value of the heat transfer coefficient is 700 W / m C, what is the length of the pipe required to raise the water temperature to 80 ° C?
A thick concrete wall having a uniform temperature of 50oC is suddenly subjected to a stream of water so that the surface temperature is suddenly lowered to 15oC. How long will it take to cool the concrete to 30oC at a depth of 5 cm from the surface? Data: concrete properties, k = 1.37 W/m×oC, r = 2100 kg/m3, a = 7.5×10-7 m2/s.
Number 3A food product with 73% moisture content in a 7 cm diameter can wants to be frozen. The density of the product is 970 kg/m³, the thermal conductivity is 1.2W/(m K), and the initial freezing temperature is -2.5°C. After 11 hours in the freezing medium -40°C, the product temperature becomes -10°C. Estimate the convection heat transfer coefficient of the freezing medium. Assume the can as an infinite cylinder. h= answer in W/(m²K)
/ Hot square plate (1 m ×1 m) is to be cooled by attaching aluminum circular pin fins (D=0.25 cm, L= 3 cm) distributed with distance 0.6 cm as illustrated in Figs.(1-a) & (1-b). If the fin base temperature is 100°C, cooling air temperature is 30°C and h= 35 W/m. °C. Determine the total rate of heat transfer from the finned plate and the effectiveness of the fins? Assume k= 237 W/m.°C and nr=tanh mL/ mL.
Water at 5°C is being used to cool apples from an initial temperature of 25° to 10°C. Thewater flow over the surface of the apple creates a convective heat-transfer coefficientof 15 W/(m2-K). Assume the apple can be described as a sphere with a 10 cm diameterand the geometric center is to be reduced to 10°C. The apple properties include thermalconductivity of 0.45 W/(m-K), specific heat of 3.950 kJ/(kg-K), and density of 940 kg/m3.a. Determine the time that the apples must be exposed to the water.b. If the apple is submerged only for 2 hours, what will be its center temperature?
Design a solar chimney to cover 75% of total heating losses, where U value for the chimney=0.5 W/m2.K and the total wall area of the spaces equal 70m2 and the temperature outside are 5oC at night and 8oC at day and the temperature for the interior is 24 oC.
You want to increase the heat flux dissipated by a tube, OD = 2.5 cm, by placing cooling fins circular. The thickness, height and thermal conductivity of the fins are: 1mm, 1.25 cm and 160 W/mC, respectively. The fins are equally spaced such that there are 100 fins for every meter of tube length. If the The outer surface temperature of the tube is 170 C, the ambient temperature is 30 C, and the transfer coefficient of heat is h = 200 W/m2K, determine the increase (percentage) in the heat flux dissipated by the tube by placing the cooling fins. Take the efficiency of each fin to be 85%.
A concrete wall of 16.44 cm thickness (k = 1.37 W / mC,? = 7x10-7 m2 / s) having a uniform temperature of 54 C in the beginning was suddenly exposed to the air flow at 10C. The convection heat transfer coefficient of air is 10 W / m2C and after a certain time, find the time taken for the center temperature of the wall to be 30 C (minutes).