Consider Problem 4.5 for the case where the plate is of square cross section,
(a)Derive an expression for the shape factor,
(b)Derive an expression for the shape factor,
(c)Evaluate the shape factors that can be used to determine the maximum and average temperatures along
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Fundamentals of Heat and Mass Transfer
- c) A steel pipe of 100 mm bore, and 10 mm bore thickness, carrying dry saturated steam at 28 bars, is insulated with a 40 mm layer of moulded insulation. This insulation in turn is insulated with a 60 mm layer of felt. The atmospheric temperature is 15 °C. Calculate: (i) the rate of heat loss by the steam per metre pipe length. (ii) the temperature of the outside Dimensions in mm surface.zzzzzzz h₂-15 W/m²K Steel k₁=50 W/mK AVALEHT Ø100 1₂ " Steam 28 bar h-550 W/m²K, Inner heat transfer coefficient = 550 W/m² K Outer heat transfer coefficient = 15 W/m² K Thermal conductivity of steel = 50 W/m K Thermal conductivity of felt = 0.07 W/m K Moulded insulation Felt Moulded insulation K₂=0.09 W/mK Thermal conductivity of moulded insulation = 0.09 W/m 40 10. A 60 15°C Felt K₁=0.07 W/mK zzzzzzzzarrow_forwardA 2.54-cm. steel bolt is used to clamp two aluminum (2014-T6, HT aged) plates together as shown by Fig. Problem 5. The aluminum plates have a total thickness of 5.08 cm. and an equivalent diameter of 5.08 cm. The bolt is heated to a temperature of 93.33 °C, the inserted in the aluminum plates, which are at 26.7 °C, and tightened so as to have a tensile tightening stress of 207 MPa in the unthreaded shank while steel at 93.33 °C. What is the tensile stress in the bolt after assembly has cooled to 26.7 °C? The deformations are elastic. Fe Aluminum Ports 2D- -D- Grip 2" B Steel- Fearrow_forwardAnswer correctly and quickly as possible please. Please help me with my last three questions, I do not have any ask an expert left. Please.arrow_forward
- The Diamond Ring Solution. The processing chip on the computer that controls the navigation equipment on your spacecraft is overheating. Unless you fix the problem, the chip will be damaged and the navigation system will shut down. You open the panel and find that the small copper disk that was supposed to bridge the gap between the smooth top of the chip and the cooling plate is missing, leaving a 2.2 mm gap between them. In this configuration, the heat cannot escape the chip at the required rate. You notice by the thin smudge of thermal grease (a highly thermally conductive material used to promote good thermal contact between surfaces) that the missing copper disk was 2.2 mm thick and had a diameter of 1.3 cm. You know that the chip is designed to run below 75 °C, and the copper cooling plate is held at a constant 5.0 °C. (a) What was the rate of heat flow from the chip to the copper plate when the original copper disk was in place and the chip was at its maximum operating…arrow_forwardPlease help me get the correct answer quickly, please. :((arrow_forward3.8 Determine (i) the pressure drop, and (ii) the convective heat transfer coefficient from hot air ( Tin = 500 K, Pin = 101.3 kPa, m sphere = 3.8 cm, o = 0.45, T init = 300 K, c sphere = 0.8 kJ/kgK, k sphere = 1.05 W/mK). = 3.5 kg/s) to a cold-packed bed of spheres (L vessel = 6.0 m, D vessel = 1.50 m, D Answer. (a) Ap = 9.46 kPa ; (b) h = 115arrow_forward
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