Consider a liquid metal
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Fundamentals of Heat and Mass Transfer
- Q4/ The cylindrical head of an engine is 1 m long and has an outside diameter of 50 mm. The temperature of outer surface is 150 °C and an ambient temperature 40 °C with a convective coefficient of 80 W/m².'C. The head has been provided with 12 longitudinal straight fine, which are 0.75 mm thick and protrude 25 cm from the cylindrical surface. Calculate the heat dissipation due to addition of fines. Take thermal conductivity is 260 W/m.°C.arrow_forwardIntroduction to heat convection Solved problems HW-10- 1- Determine the velocity distribution in the velocity boundary layer assuming second degree polynomial: u =C, +C,y+C,y? Answer: The boundary conditions are: du .. u = 0 at y = 0; u = u, ; at y = 6; = 0 at y = 8 dy 2 y This gives: يجب حفظ الشروط الحدية اذا كان الامتحان حضوري 2- Determine the velocity distribution in the velocity boundary layer assuming third degree polynomial: u = C, +C,y+C,y' +C,y' Answer: The boundary conditions are: .. u = 0 at y = 0 = 0 dy? at y = 0 du = 0 u = u, at y = 8 at y = 8 dy 3 y 1y This gives: 28 28 يجب حفظ الشروط الحدية اذا كان الامتحان حضوري 3- Determine the velocity distribution in the velocity boundary layer assuming fourth degree polynomial: 2 u = a, +a, y+a,y +a,y' +a,y Answer: The boundary conditions are: . u = 0 = 0 dy? at y = 0 at y = 0 du = 0 dy d'u at y = 6 ; dy? u = u, at y = 6 at y = 6 4. This gives: = 2 يجب حفظ الشروط الحدية اذا كان الامتحان حضوري 4- For flow over a slightly curved…arrow_forwardplz solve it within 30-40 mins I'll give you multiple upvotearrow_forward
- Correct answer pleasearrow_forwardI need the answer as soon as possiblearrow_forwardA Deep-sea Diver is wearing a wetsuit in cold water. (Natural convection, radiative transfer is negligible). The following data are given: Water Temperature Te= 10 Degrees Celsius. Wetsuit thickness is equivalent to a 8mm neoprene rubber (thermal conductivity is 0.19 W/m-K), Skin thickness is 1.45mm, Skin thermal conductivity is 0.21 W/m-k. Body temperature below skin Tb= 37 degrees Celsius. Average Air gap thickness is 1mm, air thermal conductivity = 0.027 w/m-K. a) Draw a complete equivalent thermal circuit and show all parameters. b) Calculate the flux of heat loss from the diver (in W/m^2 of body surface area) c) Calculate the temperature of the skin outer surface (Ts) d) Based on your calculations is the wetsuit adequate to keep the diver warm enough? Why?arrow_forward
- Must answer all the questions.arrow_forwardA thermocouple junction of spherical form is to be used to measure the temperature of a gas stream. h = 400w/m^2 deg C; k(thermocouple junction) = 20 w/m deg C; cp = 400 J/kg deg C; and density = 8500 kg/m^3;Calculate the following:i. Junction diameter needed for the thermocouple to have the thermal time constant of one second.ii. Time required for the thermocouple junction to reach 198 deg C if junction is initially at 25 deg C and is placed in gas stream which is at 200 deg C.arrow_forward(b) In two dimensional boundary layer, shear stress was changed linearly from the solid surface toward y-axis until it reach the value of zero at y = ở. Based on Table 2 and setting given to you; (i) Derive the equation of displacement thickness and momentum thickness using Von Karman Approximation Method ; and (ii) Determine the accuracy of this method in determining the value of displacement thickness and momentum thickness. C5 Table 2: Equation of Velocity Profile Setting Equation wU = 2y/8 - (y/S² 1arrow_forward
- An incompressible Newtonian liquid is confined between two concentric circular cylinders of infinite length— a solid inner cylinder of radius Ri and a hollow, stationary outer cylinder of radius Ro. The inner cylinder be stationary and the outer cylinder rotate at angular velocity ?o. Generate an exact solution for u?(r) using the step-by-step . The flow is steady, laminar, and two-dimensional in the r?-plane. The flow is also rotationally symmetric, meaning that nothing is a function of coordinate ? (u? and P are functions of radius r only). The flow is also circular, meaning that velocity component ur = 0 everywhere. Generate an exact expression for velocity component u? as a function of radius r and the other parameters in the problem. You may ignore gravity.arrow_forwardIn the design of a certain computer application, a heat flow simulation is required. In the simulation, the heat conductor, which is of length 10m, has a perfectly insulated surface. The temperature at both ends of the conductor is kept consistently at zero. The initial temperature at any point of the conductor is uniform at 25°C. The 1-dimensional heat equation is given as follows: for all 0arrow_forward5. Suppose that a vertical column of the atmosphere is initially isothermal from 90 to 50 kPa. The geostrophic wind is 10 ms¹ from the south at 90 kPa, 10 ms -¹ from the west at 70 kPa, and 20 ms-¹ from the west 50 kPa. Calculate the mean horizontal temperature gradients in the two layers 90-70kPa and 70-50kPa. Compute the rate of advective temperature change in each layer. How long would this advection pattern have to persist in order to establish a dry adiabatic lapse rate between 60 and 80 kPa? (Assume that the lapse rate is constant from 90-50kPa and that the 80-60 kPa layer thickness is 2.25 km. You may also assume that f = 10-4s¹ and, if necessary, p = 1kg/m³.) [Holton 3.12]arrow_forwardarrow_back_iosSEE MORE QUESTIONSarrow_forward_ios
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning