part b only please
8.12 Dry, compressed air at Tm,i 75°C, p- 1o atm, with a mass flow rate of a 30-mm-diameter, 5-m-long tube whose surface is at T, 25°C. 0.001 kg/s, enters
(a) Determine the thermal entry length, the mean temperature of the air at the tube outlet, the rate of heat transfer from the air to the tube wall, and the power required to flow the air through the tube. For these conditions the fully developed heat transfer coefficient is h 3.58 W/m2 . K
(b) In an effort to reduce the capital cost of the installation it is proposed to use a smaller, 28-mm- diameter tube. Determine the thermal entry length, the mean temperature of the air at the tube outlet, the heat transfer rate, and the required power for the smaller tube. For laminar flow conditions it is known that the value of the fully developed heat transfer coefficient is inversely proportional to the tube diameter
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8.12 Dry, compressed air at Tm,i 75°C, p- 1o atm, with a mass flow rate of a 30-mm-diameter, 5-m-...
8.12 Dry, compressed air at Tm.i75°C, p-10 atm, with a mass flow rate of 0.001 kg/s,...
8.12 Dry, compressed air at Tm.i75°C, p-10 atm, with a mass flow rate of 0.001 kg/s, enters a 30-mm-diameter, 5-m-long tube whose surface is at Ts - 25°C. (a) Determine the thermal entry length, the mean temperature of the air at the tube outlet, the rate of heat transfer from the air to the tube wall, and the power required to flow the air through the tube. For these conditions the fully developed heat transfer coefficient is h- 3.58 W/m2...
Air at a temperature Tm, i = 20°C and p = 1 atm enters a 25-mm...
Air at a temperature Tm, i = 20°C and p = 1 atm enters a 25-mm diameter, 1.75 m tube with a mass flow rate of 6 x 10-4 kg/s. A constant heat flux warms the air so that its exit mean temperature is Tm, 0 = 50°C. Find the required heat flux and wall surface temperature at the outlet. Assume fully developed flow. Step 1 What is the heat rate transfer to the air from the tube, in W?...
heat and mass transfer (20 points) Air at 25°C cools a 2170 cylindrical battery (with a diameter of 21 mm and a length of 70 mm) with a cross flow velocity of 6 m/s. a) Determine the average conv...
heat and mass transfer
(20 points) Air at 25°C cools a 2170 cylindrical battery (with a diameter of 21 mm and a length of 70 mm) with a cross flow velocity of 6 m/s. a) Determine the average convective heat transfer coefficient. (b) If the battery's internal heat generation is 5W and its thermal conductivity is 0.6 w/m-k, the determine the battery surface temperature and the maximum temperature in battery
(20 points) Air at 25°C cools a 2170 cylindrical battery...
(40 points) Engine oil flows at a rate of 1 kg/s through a 5-mm diameter smooth straight tube. Th...
(40 points) Engine oil flows at a rate of 1 kg/s through a 5-mm diameter smooth straight tube. The oil has an inlet temperature of 47°C and it is desired to heat the oil to a mean temperature of 87°C at the exit of the tube. The surface of the tube is maintained at 150°C. Assuming the flow is fully developed both hydrodynamically and thermally, determine the required length of the tube. Note: by calculating Reynolds number at the entrance...
View Policies Current Attempt in Progress - 125 Air at a temperature Tmi -20°C and p...
View Policies Current Attempt in Progress - 125 Air at a temperature Tmi -20°C and p - 1 atm enters a 25-mm diameter, 1.25 m tube with a mass flow rate of 6 x 10"W.A constant heat flux warms the air so that its exit mean temperature is Tm.o -50°C. Find the required heat flux and wall surface temperature at the outlet. Assume fully developed flow.
Problem 3: (35pts) Atmospheric air enters the heated section of a circular tube at a flow...
Problem 3: (35pts) Atmospheric air enters the heated section of a circular tube at a flow rate of 0.005 kg/s and a temperature of 30°C. The tube is of diameter D =60mm, and fully developed conditions with h = 30W/m2K exist over the entire length of L-4m. Take cp-1015 /kg.K 2 (a) (10pts) For the case of uniform surface heat flux at q"-1000W/m, determine the total heat transfer rate q and the mean temperature of the air leaving the tube...
An oil preheater consists of a single tube of 30-mm diameter and 7-m length, with its...
An oil preheater consists of a single tube of 30-mm diameter and 7-m length, with its surface maintained at 200°C by swirling combustion gasses. The engine oil enters at 90°C and comes out at 144°C. Assume the flow is laminar and both hydraulically and thermally fully developed. Answer the following questions: (a) What flow rate must be supplied to maintain the oil outlet temperature of 144°C? (b) What is the corresponding heat transfer rate? (c) Discuss how you may refine...
Problem 3 (20 points) A cross-flow heat exchanger consists of a bundle of 32 tubes in a long duct. Hot water at 150°C and a mean velocity of 0.5 m/s enters the tubes having inner and outer diameters...
Problem 3 (20 points) A cross-flow heat exchanger consists of a bundle of 32 tubes in a long duct. Hot water at 150°C and a mean velocity of 0.5 m/s enters the tubes having inner and outer diameters of 10.2mm and 12.5mm and has to be cooled to 136°C. The tubes are made of steel of thermal conductivity k-40 W/m.K. Air at 10°c enters the exchanger (unfinned) with a volumetric flow rate of 1.0 m3/s. The convective heat transfer coefficient...
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the examinatiU to Heat Transfer" by Frank P. Incropera and Bavid F. Air entering a circular...
the examinatiU to Heat Transfer" by Frank P. Incropera and Bavid F. Air entering a circular stainless steel tube D 50 mm outside diameter by d 45 mm inside diameter by L 5 m long atTa 20 C is heated by saturated steam at T100 c through which the tube passes. The thermal conductivity of the stainless steel tube kss .. 16.3 w/m° ? and the heat transfer coefficient at the interface between the tube and the steam h. 5000...
8.12 Dry, compressed air at Tm.i75°C, p-10 atm, with a mass flow rate of 0.001 kg/s, enters a 30-mm-diameter, 5-m-long tube whose surface is at Ts - 25°C. (a) Determine the thermal entry length, the mean temperature of the air at the tube outlet, the rate of heat transfer from the air to the tube wall, and the power required to flow the air through the tube. For these conditions the fully developed heat transfer coefficient is h- 3.58 W/m2...
Air at a temperature Tm, i = 20°C and p = 1 atm enters a 25-mm diameter, 1.75 m tube with a mass flow rate of 6 x 10-4 kg/s. A constant heat flux warms the air so that its exit mean temperature is Tm, 0 = 50°C. Find the required heat flux and wall surface temperature at the outlet. Assume fully developed flow. Step 1 What is the heat rate transfer to the air from the tube, in W?...
heat and mass transfer
(20 points) Air at 25°C cools a 2170 cylindrical battery (with a diameter of 21 mm and a length of 70 mm) with a cross flow velocity of 6 m/s. a) Determine the average convective heat transfer coefficient. (b) If the battery's internal heat generation is 5W and its thermal conductivity is 0.6 w/m-k, the determine the battery surface temperature and the maximum temperature in battery
(20 points) Air at 25°C cools a 2170 cylindrical battery...
(40 points) Engine oil flows at a rate of 1 kg/s through a 5-mm diameter smooth straight tube. The oil has an inlet temperature of 47°C and it is desired to heat the oil to a mean temperature of 87°C at the exit of the tube. The surface of the tube is maintained at 150°C. Assuming the flow is fully developed both hydrodynamically and thermally, determine the required length of the tube. Note: by calculating Reynolds number at the entrance...
View Policies Current Attempt in Progress - 125 Air at a temperature Tmi -20°C and p - 1 atm enters a 25-mm diameter, 1.25 m tube with a mass flow rate of 6 x 10"W.A constant heat flux warms the air so that its exit mean temperature is Tm.o -50°C. Find the required heat flux and wall surface temperature at the outlet. Assume fully developed flow.
Problem 3: (35pts) Atmospheric air enters the heated section of a circular tube at a flow rate of 0.005 kg/s and a temperature of 30°C. The tube is of diameter D =60mm, and fully developed conditions with h = 30W/m2K exist over the entire length of L-4m. Take cp-1015 /kg.K 2 (a) (10pts) For the case of uniform surface heat flux at q"-1000W/m, determine the total heat transfer rate q and the mean temperature of the air leaving the tube...
An oil preheater consists of a single tube of 30-mm diameter and 7-m length, with its surface maintained at 200°C by swirling combustion gasses. The engine oil enters at 90°C and comes out at 144°C. Assume the flow is laminar and both hydraulically and thermally fully developed. Answer the following questions: (a) What flow rate must be supplied to maintain the oil outlet temperature of 144°C? (b) What is the corresponding heat transfer rate? (c) Discuss how you may refine...
Problem 3 (20 points) A cross-flow heat exchanger consists of a bundle of 32 tubes in a long duct. Hot water at 150°C and a mean velocity of 0.5 m/s enters the tubes having inner and outer diameters of 10.2mm and 12.5mm and has to be cooled to 136°C. The tubes are made of steel of thermal conductivity k-40 W/m.K. Air at 10°c enters the exchanger (unfinned) with a volumetric flow rate of 1.0 m3/s. The convective heat transfer coefficient...
the examinatiU to Heat Transfer" by Frank P. Incropera and Bavid F. Air entering a circular stainless steel tube D 50 mm outside diameter by d 45 mm inside diameter by L 5 m long atTa 20 C is heated by saturated steam at T100 c through which the tube passes. The thermal conductivity of the stainless steel tube kss .. 16.3 w/m° ? and the heat transfer coefficient at the interface between the tube and the steam h. 5000...
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