Air at a mean temperature of 50 F flows over a thin-wall 1-in. O.D. tube, 10 feet in length, which has condensing water vapor flowing inside at a pressure of 14.7 psia. Compute the heat transfer rate if the average heat transfer coefficient between the air and tube surface is
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- Only answer if you are 100% sure otherwise i will downvote... An ASTM B75 copper tube sheathes a heating element that is used to boil water at 1254 kPa. The copper tube is immersed horizontally in the water, and its surface is polished. The tube diameter and length are 5 mm and 9.5 cm, respectively. The maximum use temperature for ASTM B75 copper tube is 204°C. Determine the highest evaporation rate of water that can be achieved by the heater without heating the tube surface above the maximum use temperature. Use the property tables to calculate the properties of water at saturation temperature. The surface tension 0 at 190°C is 0.03995 N/m. Also, Csf 0.0130 and 10 for the boiling water on a polished copper surface. The highest evaporation rate of water is g/s?arrow_forwardWater going into a pipe with a tempeture of T1 and going out T2 . ambient tempeture is T0. Develop an expression for T2 ( based on heat transfer) Length of the pipe Lh0 - convective heat transfer coefficient of the airhW -convective heat transfer coefficient of the waterk- pipe thermal conductivity (W/m·K)d – pipe diameter Use any other varilable that you need and can be found online easily .arrow_forwardA thick-walled cylinder tubing of hard rubber having an inside radius of 20mm is being used as temporary cooling coil in a bath. Ice water is flowing rapidly through inside tube and the inside wall temperature is 274.9K. The outside surface temperature is 297.1K. A total of 14.65W must be removed from the bath by cooling coil. How many m of tubing are required?arrow_forward
- Q2:A) Define the bulk temperature (Tn), and prove that : T₁, - 2 ur dr B) Ethylene glycol flows at 0.01 kg/s through a 3 mm diameter, thin walled_tube. The tube is coiled and submerged in a well-stirred water bath maintained at 25 °C. If the fluid enters the tube at 85 °C, what heat rate and tube length are required for the fluid to leave at 35 °C ? At 60 °C, μ = 0.00522 kg/m.s, k = 0.26 W/m.K, C, 2562 J/kg.K. -arrow_forward48. Water is flowing in a smooth pipe of diameter D. A section of this pipe hav- ing a length of L is heated. Water at the inlet to the heated section has a tempera- ture of Tŋ. Water temperature at the exit of the heated section is Tp. The heated section of the pipe wall is maintained at a constant heat flux so that a constant temperature difference of AT, = T, – T, exists between the wall and the bulk wa- ter temperature. Show that for turbulent flow in the pipe and a specified heated length and pipe diameter, water temperature at the exit of the heated section is given by: 402 0.6 Pr T52 =Tf +0.0876 L AT DO.8 0.2 marrow_forwardCurrent Attempt in Progress Consider pressurized water, engine oil (unused), and Nak (22 %/78%) flowing in a 20-mm-diameter tube. (a) Determine the mean velocity, in m/s, the hydrodynamic entry length, in m, and the thermal entry length, in m, for each of the fluids when the fluid temperature is 366 K and the flow rate is 0.014 kg/s. (b) Determine the mass flow rate, in kg/s, the hydrodynamic entry length, in m, and the thermal entry length, in m, for water and engine oil at 300 and 400 K and a mean velocity of 0.018 m/s. Part A Your answer is incorrect. Determine the mean velocity, in m/s, the hydrodynamic entry length, in m, and the thermal entry length, in m, for each of the fluids when the fluid temperature is 366 K and the flow rate is 0.014 kg/s. Liquid water engine oil Nak (m/s) ! i XALA(M) xer (m) Attempts: unlimited Submit Answerarrow_forward
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