The strength and stability of tires may be enhanced by heating both sides of the rubber
(a) If steam flow over the tire surfaces maintains a convection coefficient of
(b) To accelerate the heating process, it is recommended that the steam flow be made sufficiently vigorous to maintain the tire surfaces at 200°C throughout the process. Compute and plot the midplane and surface temperatures for this case, as well as for the conditions of part (a).
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Introduction to Heat Transfer
- Please quicklyarrow_forwardAn ice chest is constructed of Styrofoam [k = 0.033 W/m.°C] with inside dimensions of 25 by 40 by 100 cm. The wall thickness is 5.0 cm The outside of the chest is exposed to air at 25°C with N=10 W/m2°C. If the chest is completely filled with ice, calculate the time for the ice to completely melt. State your assumptions. The enthalpy of fusion for water is 330 kJ/kgarrow_forward2 (a) A short bronze cylinder of diameter 6 cm and length 12 cm is initially at 40°C and then plunged into a fluid at 200°C. The temperature at the centre of the cylinder is measured by a thermocouple to be 150°C after 5 minutes. What is the convective heat transfer coefficient between the cylinder and the fluid? The following properties of the bronze cylinder may be used: Thermal conductivity k = 26 W/m-K, density p = 8800 kg/m², and specific heat c = 420 J/kg-K. State and justify all assumptions made.arrow_forward
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- Classify whether the properties given is for subcooled liquid (SC), saturated liquid (SL), wet mixture (WM), saturated vapor (SsV), superheated vapor (SP) or saturated (S) (can be liquid or vapor) kJ Tsat = 160°C, u = 1000- kg m3 Tsat = 200°C, v = 0.01234 kg Tsat = 200°C, P = 1.5549 MPa 1. Psat = 0.14 MPa,T = 0°C 2. Psat = 1.0 MPa, T = 100°C 7. Peat = 1.4 MPa,T = 150°C kJ Pzat = 0.14 MPa, h = 2000- kg k] Psat = 1.5 MPa, s = 7- kg – K 3. %3D 8. Tsat = 191°C, v = 0.00114291- m3 kg m3 Tsat = 193°C, v = 0.14685 kg 9. 5. 10. sc SL WM sv SP 1 2 3 4 7 8 9 10 6.arrow_forwardA dead body was found within a closed room of a house where the temperature was a constant 66 °F. At the time of discovery, the core temperature of the body wasdetermined to be 88 ° F. One hour later a second measurement showed that the core temperature of the body was 75 ° F. Assume that the time of death corresponds to t = 0 and that the core temperature at that time was 98.6 ° F. Determine how many hours elapsed before the body was found. Type your answer in hours in the space provided below. Round your answer to one decimal place.arrow_forwardSample Problem • Four metric tons of pork are to be stored at a temperature of -12°C in 8 hours. The product enters the chiller at a temperature of 21°C and the specific heats above and below freezing are 0.86 kCal/kg-°C and 0.51 kcal/kg-°C, respectively, and its latent heat of fusion is 48 kCal/kg. If the freezing temperature of the product is -5°C, determine the product load in kCal/hr. TCLarrow_forward
- Problem #2: A mass of ice at -4°C is needed to cool 115 kg of vegetables in a bunker for 24 hours. The initial temperature of the vegetables is assumed to be 29°C. It is also assumed that, within the 24-hr period, the average temperature inside the bunker is 7°C. If the heat gained per hour in the bunker is 30% of the heat removed to cool the vegetables from 29°C to 7°C, what would be the required mass of ice in kg? Use: Specific heat of water 4.2292 kJ/kg-°C • Specific heat of ice 1.9387 kJ/kg-°C Specific heat of vegetables 3.35 kJ/kg-°Carrow_forwardQ1: (5pt) In a cylindrical fuel element for a gas-cooled nuclear reactor, the generation rate of thermal energy within the fuel element due to fission can be approximated by the relation q(1) W/m³ %3D where a is the radius of the fuel element and is constant.The boundary surface at r = a is maintained at a uniform temperature Tɔ. (a) Assuming one-dimensional, steady-state heat flow, develop a relation for the temperature drop from the centreline to the surface of the fuel element. (b) For a radius of a = 30 mm, the thermal conductivity k = 10 W/(m °C) and qo = 2 x 107 W/m³, calculate the temperature drop from the centreline to the surface. 02: (5pt)arrow_forwardQUESTION FIVE (a) At a certain location, wind is blowing steadily at 10 m/s. Determine the mechanical energy of air per unit mass and the power generation potential of a wind turbine with 60-m-diameter blades at that location. Take the air density to be 1.25 kg/m3. (b) Consider an alcohol and a mercury thermometer that read exactly 0°C at the ice point and 100°C at the steam point. The distance between the two points is divided into 100 equal parts in both thermometers. Do you think these thermometers will give exactly the same reading at a temperature of, say, 60°C? Explain.(c) Determine the work required to deflect a linear spring with a spring constant of 70 kN/m by 20 cm from its rest position.arrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning