Consider a 2-m-high electric hot-water heater that has a diameter of 40 cm and maintains the...
Exercise 10 Consider a 2-m-high electric hot water heater that has a diameter of 40 cm and maintains the hot water at 55°C. The tank is located in a small room whose average temperature is 27°C, and the heat transfer coefficients on the inner and outer surfaces of the heater are 50 and 12 W/m2.°C, respectively. The tank is placed in another 46-cm-diameter sheet metal tank of negligible thickness, and the space between the two tanks is filled with foam...
A copper hot water pipe (outer diameter ½”) has an exterior temperature of 49oC. For insulation,it is wrapped in polyethylene foam that is ½” thick. If the pipe is 12 feet long and runs through a utility room whose temperature is 7oC Find the rate at which heat is lost through the insulation. Polyethylene foam has a thermal conductivity of 0.024W/(m·K) (Hint: use the outer surface area of the insulation)
A 150 L (= 40 gal) electric hot-water tank has a 5.0 kW heater. How many minutes will it take to raise the water temperature from 61.0 F to 151 F? Express your answer with the appropriate units.
system, hot water at an average temperature of 80°C is flowing through a 15-m section of a cast In a heating iron pipe (k 50 W/m K) whose inner and outer diameters are 4 cm and 5 cm, respectively. The outer surface of the pipe, whose emissivity is 0.75, is exposed to the cold air at 10°C in the basement. with a heat transfer coefficient of 15 W/m2.K. The heat transfer coefficient at the inner surface of the pipe is...
A 150 L (~ 40 gal) electric hot-water tank has a 5.0 kW heater. Part A How many minutes will it take to raise the water temperature from 63.0 F to 145 F? Express your answer with the appropriate units. DÅ o o ? 75.6 min Submit Previous Answers Request Answer X Incorrect; Try Again; 2 attempts remaining
In a food processing facility, a spherical container of inner radius n = 40 cm, outer radius r2 = 41 cm, and thermal conductivity k = 1.5 W/m 'C is used to store hot water and to keep it at 100°C at all times (see Figure Q2). To accomplish this, the outer surface of the container is wrapped with a 500-W electric strip heater and then insulated. The temperature of the inner surface of the container is observed to be...
3. A 20 cm diameter cooking is over a heater boiling water at 100°C. The bottom of the pan is 1 cm thick and the inside surface temperature of the bottom plate in contact with water is 110°C. determine the convective heat transfer coefficient of the boiling water. 'fthe ratcof heat trausfen is 500 watts
3. Hot water at an average temperature of 60°C and an average velocity of 0.6 m/s is flowing through a 5- m section of a thin-walled hot water pipe that has arn outer diameter of 2.5 cm. The pipe passes through the centre of a 14 cm-thick wall filled with fiberglass insulation (k-0.035 W/rm C), If the surfaces of the wall are at 18 C, determine (a) the rate of heat transfer from the pipe to the air in the...
Q4 04(12%) Water is to be heated from 10°C to 80°C as it flows through a 2-cm-internal-diameter, 7-m-long tube. The tube is equipped with an electric resistance heater, which provides uniform heating throughout the surface of the tube. The outer surface of the heater is well insulated, so that in steady op eration all the heat generated in the heater is transferred to the water in the tube. If the system is to provide hot water at a rate of...
Exercise 1.17 A pipe with a diameter of 10 cm is surrounded by a sheet-metal clad insulation of 20 cm mineral wool (A = 0,045 W/m K). a) What is the heat loss per meter of pipe when the pipe is 90 C warm and the sheet metal sheath of the insulation shows 40 °C? b) In a section of track, the insulation was incorrectly applied 10 cm eccentrically. What is the heat loss per meter of pipeline? The temperature...