heat and mass transfer An uninsulated steam pipe of 100-mm diameter is routed through a building whose walls and air are at 27°C. Pressurized steam maintains a pipe surface temperature of 147°C, and the coefficient associated with natural convection is h =10 W/m2.K. The surface emissivity is ɛ= 0.8. What is the rate of heat loss per unit length from the steam line?

heat and mass transfer An uninsulated steam pipe of 100-mm diameter is routed through a building whose walls and air are at 27°C. Pressurized steam maintains a pipe surface temperature of 147°C, and the coefficient associated with natural convection is h =10 W/m2.K. The surface emissivity is ɛ= 0.8. What is the rate of heat loss per unit length from the steam line?

Similar questions

4) A ground source heat pump heats a building by extracting heat from the ground and pumping it into the building. Define: Qc = heat extracted from the ground, Qn= heat pumped into the building, W = electric energy used by the heat pump, Tc= temperature of the ground, T = temperature of building (Qc, Qn, and W are positive by definition). Assume Tr > Tc. a) Draw a diagram showing energy flow in and out of the heat pump. b) Write a general expression for the change AS in the entropy of the "universe", that is the heat pump plus the cold and hot reservoirs, in terms of the quantities defined above. Now assume ideal (reversible) operation, and take Te= 10 °C and Tp= 20 °C. What is the coefficient of performance (ČOP) of the heat pump? By what factor would this change if we had Tc = 0 °C instead?
An aluminum cup contains 225 g of water and a 40-g copper stirrer, all at 27°C. A 492-g sample of silver at an initial temperature of 86°C is placed in the water. The stirrer is used to stir the mixture gently until it reaches its final equilibrium temperature of 32°C. Calculate the mass of the aluminum cup. ?g
QUESTION 9 During the video on heat conduction, H through a single pane window was calculated. Now, consider a window that has wo panes with a 6 mm air gap between them. Each pane has an area of 1.9 m. The window separates the inside of a house at 22 °C from the outside at 0°C. Let Kair = 0.03 W/(m-K). Hint: This problem can be simplified by noting that the thermal conductivity of glass is much greater than air, so the effect of the glass on the total conductivity can be ignored. Therefore, the purpose of the two glass panes is to support the layer of air between them. Calculate the heat current H through the double glass pane window in watts. Do not include units in your answer and state your numerical answer in normal form. QUESTION 10 Consider process 3 in the figure below (or in First_Exam_Figures.pdf) shown by the bold solid line with an arrowhead. The pressure of a gas is decreased at constant volume. V. Click Save and Submit to save and submit. Click Save All Ansuers to save all…
A2.9 kg lump of aluminum is heated to 95°C and then dropped into 10.0 kg of water at 5.0°C. Assuming that the lump-water system is thermally isolated, what is the system's equilibrium temperature? Assume the specific heats of water and aluminum are 4186 and 900 J/kg-K, respectively. Number i Units
6
A copper sample (ccu = 387 J/kg•K) of mass mẹ = 75 g and temperature Te = 312ºC is dropped into a glass beaker that contains a mass of water me = 220 g (cw = 4190 J/kg•K). %3D The initial temperature of the water and the beaker is Tw,b = 12.0°C. What is the final temperature of the copper, beaker, and water? * The heat capacity (the specific heat times the mass) of the beaker is Cb' = 190 J/K.
0.4 kg water is at room temperature 23 degrees in an aluminum container. An unknown metal with 0.5 kg mass is placed inside the water raising its temperature to 40 degrees. A)What is the specific heat of the unknown metal. B) Would the equilibrium temperature greater, less or the same if the system was not properly isolated.
2.12 A mass of 5 kg of water is contained in a piston-cylinder device at 125 kPa. Initially, 2 kg of the water is in the liquid phàse and the rest is in the vapor phase. Heat is now transferred to the water, and the piston, which is resting on a set of stops, starts moving when the pressure inside reaches 300 kPa. Heat transfer continues until the total volume increases by 20%. a) Determine the initial and final temperatures. b) Calculate the mass of liquid water when the piston first starts moving. c) Calculate the work done during this process. d) Show the process on a P-V diagram
1 Thermal Expansion A steel rod is 3.000 cm in diameter at 25 °C. A brass ring has an inner diameter of 2.992 cm at 25 °C. At what common temperature – i.e., the same temperature for the rod and ring – will the ring just fit onto the rod? The coefficient of linear expansion of steel is 11 x 10-6/°C. The coefficient of linear expansion of brass is 19 x 10-6/°C.