8) Air flows over a flat plate at a velocity of 20 m/s and a temperature...
Air flows with a velocity of 20 m/s over a flat plate of length 2 m. The air properties are k = 0.030 W/mK, V = 20.92 x 10-6 m/s, Pr=0.700. a. What type(s) of flow (laminar/turbulent) exist on this plate? b. If the following relations are given for the laminar and turbulent local convection coefficients over the plate, haminar (x) = 20 houwbudemo (x) = .52 where x is the distance from the plate leading edge. Find the average...
4) Air at 101 kPa and 360 K flows at 15 m/s over a flat plate maintained at 300 K Assume that the transition Reynolds number is 5x10 (0.332R 12Pr1/3 Re < 5 x 105 0.029Repr0:43 5 x 105 < Re <3 x 107 Assume that k-0.03 W/( mK), 20x10* m?ls, Pr-0.7.p=1.16 kg/m a) If the plate is 2 m long, sketch the local heat transfer coefficient over the plate. Specify the functional form of h with respect tox b)...
Air at a temperature of 300 K flows over one side of a flat plate of width 1 m at a velocity of 20 m/s. The plate has a constant surface temperature of 350 K. Assume Re(x,c)=5x10^5. a) What is the velocity boundary layer thickness at the end of the plate if L=0.25 m? What if L=1 m? b) Calculate the drag on the plate if L=0.25 m. What is the drag if L=1 m? c) Find the heat transfer...
Air at T=25°C and pressure P=1 bar flows over a square plate with a velocity V=1 m/s. This plate has a length L= 1 m and it is heated over its entire length; the plate temperature is constant Tp=100°C. The following data are given. For air: dynamic viscosity: mu = 1.9*10–5 kg/(m.s); density: rho = 1.05 kg/m3; conductivity k = 0.03 W/(m K); Specific heat Cp = 1.007 kJ/(kg K); Prandtl number Pr = 0.7 For laminar flow over a...
Consider air flows with velocity of U?=U= 10 m/s over a semi-finite smooth flat plate with L=97 cm long. Calculate the followings by assuming ? = 1.568 x 10-5 m2/s and ?=1.177 kg/m3. Figure 1 : Boundary layer over a flat plate Consider air flows with velocity of U?=U=10 m/s over a semi-finite smooth flat plate with L=97 cm long. Calculate the followings by assuming ? = 1.568 x 10-5 m2/s and ?=1.177 kg/m3. b) Under some flow and boundary...
Problem 1: Atmospheric air at 25°C flows over both surfaces of 2 m long flat plate maintained at 125°C. For upper surface, velocity of air is 1 m/s and for lower surface, velocity is 10 m/s. (Rex,c = 5x105) (a) Determine the flow condition for upper and lower surfaces. (Laminar, or turbulent). If the condition is that laminar to turbulent is taking place, calculate the position where transition from the laminar to turbulent happens. (b) Determine the rate of heat...
Exercise 2 Air at 20 °C and 1 atm flows over a flat plate at 50 m/s. The plate is 300 cm long and is maintained at 60C. The width of the plate is 2 m. The critical Rec = 5 x 105 The properties are Conductivity k = 0.0263 W/mK, kinematic viscosity nu = v = 15.89 x 10-6 m²/s, Prandtl number is Pr=0.707 Density rho = p = 1.128 kg/m3 1. Determine the critical length Xc 2. Determine...
2. (25 pts) Engine oil flows with a velocity of 6 m/s over a flat plate having 1m length and 1 m width. The oil has a free stream temperature To= 80 °C and the plate surface temperature is maintained at Ts = 0 °C. a. Determine whether the flow over the plate transitions to turbulent regime. b. Calculate the average friction factor and the average heat transfer coefficient for the plate by using the appropriate correlations. c. Calculate the...
Air at 20 °C and 1 atm. flow over a flat plate with 35 m/s. The size of the plate is 75 cm by 75 cm and is maintained at 60 °C. Calculate: a) The heat transfer rate 40 cm from the leading edge of the plate. b) The heat transfer rate at the end of the plate (at x = L). c) The heat transfer rate from the entire plate. d) The heat transfer rate at the...
Air at atmospheric pressure and a temperature of 25°C is in parallel flow at a velocity of 5 m/s over a 1-m-long flat plate that is heated from below with a uniform heat flux of 1250 W/m2. Assume the flow is fully turbulent over the length of the plate. Evaluate properties at 325 K. (a) Calculate the plate surface temperature, Ts(x), in °C, and the local convection coefficient, hx(x ), in W/m2.K. at x = 0.2 m. (b) Calculate the...