A steam is flowing through a 5.7 m long of steel tube that has inner and outer radii of r, = 0.015 and r, 0,024 m, and a thermal conductivity of 0.14 W/m.K. The steam and the outer surface of the tube is maintained at constant temperature of 150 °C and the air = 25 °C, h = 0.35 W/m2.k) is surrounding the tube. To prevent the outer surface of the steel from the environmental conditions, a material that has a thermal conductivity of 0.014 W/m.k is wrapped over the outer surface of the steel. What is the maximum heat transfer from the steam to the air (W)? NOTE: Enter your answer. Answer Air Th Steam Steel Tr 111 To

Heat Transfer Lesson The temperature will be increased from 10 (Degree Celsius oC) to 90 (Degree Celsius oC) while the water flows through a 1.5 cm inner diameter and 7 meter long straight pipe. Equipped with electric heater on the entire surface of the pipe. Even heating throughout. The outer surface of the heater is well insulated and therefore all heat generated in the heater in continuous operation is transferred to the water in the pipe. If the system provides a hot water flow rate of 6 liters / minute. (Thermophysical properties of water at 50 oC:ρ = 988 m3/kg, k= 0.6305 W/m oC, cp=4181 J/kg oC, Pr=3.628, μ= 0.0005471 kg/m.s ) a)Find the power of the resistance heater [W]. b)Calculate the inner surface temperature [oC] of the pipe at the outlet. c)Find the pressure drop [Pa]. d)Find the pump power [W] required to overcome this pressure drop.

A 30-cm-radius metallic sphere is having thermal conductivity of k = 100. overall density of W 7 mk p = 1500- kg m² and heat capacity of C₂ = 3000 The sphere is initially at a uniform temperature of kgk CO T₁ = 20°C and is dropped into boiling water at T = 90°C. The convective heat transfer coefficient is assumed to be only h = 50; W m²K Using lump model, compute the temperature of the sphere after t = 1200 seconds. In solving this problem, please use and show the following steps (do not use EES) 1. Compute the volume and surface area 2. Compute the characteristic length Lc = k p Cp h Lc 4. Compute the Biot number Bi k 5. Calculate the Fourier number Fo= (at)/Lc² 6. Calculate the excess temperature using 0 = exp(-Bi * Fo) T-Too 7. Compute the target temperature T using 0 = Ti-Too 3. Compute the diffusivity a = = the sphere Vol Vol As == 3 r³ and А¸ = 4πr²

What is the product of overall heat transfer coefficient and area (UA) for a heat transfer equipment with the geometry as shown in the diagram? The inner tube (the shaded area in the figure) is made of a material with thermal conductivity of 1.2 W/m.K. The convection coefficient of the hot fluid (in the inner tube) is 25 W/m².K and that of the cold fluid is 12 W/m².K. The dimensions shown in the figure are r₁ 0.1 m, r₂ = 0.15 m, and r3 = 0.3 m. The length is 1 m. 4.86 W/ Cold Fluid Hot Fluid TI =