A sausage with physical properties = 980 kg / m3; cp = 3.9 kJ / kg. ° C and k = 0.76 W / m. ° C is 20 cm long and can be thought of as a 3 cm diameter cylinder. This sausage with an initial temperature of 6 ° C It is thrown into boiling water at 100 ° C. The heat transfer coefficient on the surface of the sausage is 750 W / m2. ° C is estimated to be. Considering that the sausage is cooked when the center temperature reaches 60 ° C, Calculate how long the sausage will be cooked in water.

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

Calculate the tons of refrigeration required to freeze in 4 hrs 3 mm of 10 deg C water on askating rink 61 m x 30 m if the ground temperature is 10 deg C and the air temperatureabove the rink is 16 deg C .The heat transfer coefficient from the air to O deg C is 6.8 W/m2.Cand the heat transfer from the ground to ice is 0.3402 W/m2.C

Hi, can you help me with the following problem? A thermally insulated tank of water 2 m x 2 m, depth 1 m is stirred with a paddle for threehours. If the paddle is driven by a motor whose shaft power is 8 kW determine the rate ofchange of temperature in degrees C per hr and the increase in temperature of the water.The specific heat of water is 4200 J/kgC. Identify a system and start your analysis from anappropriate form of the Fist Law of Thermodynamics

P34.9 Two parallel metal plates separated by 1 cm are held at 300, and 298 K, respectively. The space between the plates is filled with N2 (or = 0.430 nm² and Cv, m = 5/2 R). Cv.m Determine the heat flux between the two plates in units of W cm².

1. Water (C, = 4180 J/kg-K) enters a 4-cm-diameter tube at 15°C at a rate of 0.06 kg/s. The tube is subjected to a uniform heat flux of 2500 W/m: on the surfaces. Compute for the length of the tube required in order to heat the water to 45°C.

A hot steel ball of 5 mm in diameter initially at 100 oC is left to cool down in air at 20 oC.  Assume a constant convective heat transfer coefficient h = 15 W/m2K through the course of the cooling process. Cp, steel = 0.49 kJ / kg K , k,steel = 45.0 W / m K , rho, steel = 7800 kg/m^3 Cp,air = 1.00 kJ/kg K ; k_air = 0.025 W / m K; rho,air = 1.2 kg/m^3  a) Calculate the rate of convective heat transfer when the steel ball is uniformly at 100 oC.   b) Assuming the steel as a lumped system, find the temperature of the steel ball after 0.5 s.

a) A turbine blade 6 cm long and having a cross sectional area 4.65 cm and perimeter 12 cm is made of stainless steel (k=23.3 Wim K). The temperature at the root is 500 C. The blade is exposed to a hot gas at 870 °C. The heat transfer coefficient between the blade surface and gas is 442 W/im K. Determine the temperature distribution and rate of beat flow at the root of the blade, Assume the tip of the blade to be insulated. b) The hot combustion gases of a fumace are separated from the ambient air and its surounding, which are at 20°C, by a brick wall 0.5 m thick. The brick has a themal conductivity of 5 W/mk and a surface emissivity of 0.6. Under steady-state conditions an Page no.1 of 1 outer surface temperature of 120°C is measured Free convection heat transter to the air adjoining the surface is characterized by a convection coefficient of 15 Wim K What is the brick inner surface temperature

A copper bar (2.00 cm by 2.00 cm and 10.0 cm long) is welded end to end to a brass bar of the same dimensions. The free end of the copper bar is placed in a steam bath and the free end of the brass bar is placed in an ice bath. If the system is at steady state condition and that both bars are properly insulated. (Given the thermal conductivity of copper is 390 W m-1 °C-1 and he thermal conductivity for brass is 110 W 1°C1) a.) What is the temperature T at the interface of the copper-brass bar? b.) How much thermal energy flows through the bar per minute?

3.4 Estimate the rate of heat loss due to radiation from a covered pot of water at 95 ° C. How does this compare with the 60 W that is lost due only to convection and conduction losses? What amount of energy input would be needed to maintain the water at its boiling point for 30 minutes? The polished stainless steel pot is cylindrical, 20 cm in diameter and 14 cm high, with a tight-fitting flat cover. The air temperature in the kitchen is about 25 ° C. State any assumptions you make in deriving your estimates