Air at 20°C and a velocity of 8 m/s flows over the 4-m length of a...

Air at 20°C and a velocity of 8 m/s flows over the 4-m length of a 4-m wide single surface of a square plate whose temperature is 80°C. (For properties of air, use k = 0.02735 W/m·K, Pr = 0.7228, ν = 1.798 x 10-5 m2 /s ) Given the above information, do the calculations to answer the two MC questions below. Please clearly show/discuss your solution method and calculations. A. __________The rate of heat transfer, Q̇ , from this surface is most nearly: a) 7380 W b) 8980 W c) 11,200 W d) 14,500 W e) 20,400 W

B. _______The length of the surface for which the flow is likely to remain laminar is most nearly: a) 0.9 m b) 1.1 m c) 1.3 m d) 2.5 m e) 3.7m

Expert Solution

Ally Wells answered 1 year ago

Air flows over a 4 meter long flat plate at a velocity of 8 m/s. Using...

Air flows over a 4 meter long flat plate at a velocity of 8 m/s. Using a spreadsheet, calculate the boundary layer thickness and wall shear stress at 0.1 meter intervals along the plate. Do not plot the wall shear stress at x=0. Use a transition Reynolds number of 5 x 10^5 . (You will need to calculate Rex at each location to determine if the laminar or turbulent correlations should be used.) Generate a spreadsheet table that includes columns...

Air at 25°C flows over a 10-mm-diameter sphere with a velocity of 20 m/s, while the...

Air at 25°C flows over a 10-mm-diameter sphere with a velocity of 20 m/s, while the surface of the sphere is maintained at 75°C. What is the rate of heat transfer from the sphere? q = ___ W ? Please provide correct final answer for guaranteed thumbs up rating !

Air at 20°C and 1 atm flows over a spherical object at 1 m/s. The sphere...

Air at 20°C and 1 atm flows over a spherical object at 1 m/s. The sphere has a diameter of 10mm and its initial temperature is 134°C. If the density, specific heat, and conductivity of the sphere are 7832 kg/m”, 549 J/kg.K, and 49.2 W/m.K, respectively, calculate the temperature at the center of the sphere after 100 seconds.

Air at 20°C (1 atm) is flowing over a 0.025-m diameter sphere with a velocity of...

Air at 20°C (1 atm) is flowing over a 0.025-m diameter sphere with a velocity of 3.5 m/s. If the surface temperature of the sphere is constant at 80°C, determine the Reynolds number corresponding to the sphere, its average drag co-efficient, and the heat transfer rate from the sphere. The properties of air (1 atm) at the free stream temperature T∞ = 20°C, ρ = 1.204 kg/m3, k = 0.02514 W/m∙K, μ = 1.825 × 10−5 kg/m∙s, and Pr = 0.7309. At the surface temperature Ts= 80°C: μs =...

Air at 25°C is flowing over 400°C hot iron ball with a velocity of 10 m/s....

Air at 25°C is flowing over 400°C hot iron ball with a velocity of 10 m/s. The diameter of the iron ball is 10 cm diameter and (p =7874 kg/m3 and cP = 450 J/kg.K). After a while the surface temperature of the ball drops to 300°C. Determine the average rate of heat transfer from the ball. How long will it take to drop from 400°C to 300°C. Calculate the drag force. (The surface of the ball is smooth.)

Air flows through a 0.25-m-diameter duct. At the inlet the velocity is 300 m/s, and the...

Air flows through a 0.25-m-diameter duct. At the inlet the velocity is 300 m/s, and the stagnation temperature is 90°C. If the Mach number at the exit is 0.3, determine the direction and the rate of heat transfer. For the same conditions at the inlet, determine the amount of heat that must be transferred to the system if the flow is to be sonic at the exit of the duct.

Consider atmospheric air at a velocity of V = 20 m/s and a temperature of T=...

Consider atmospheric air at a velocity of V = 20 m/s and a temperature of T= 20C, in cross flow over 10 mm square tube at 45 degrees, maintained at 50C. Sketch Assumptions Calculate the air properties (show the interpolation steps) Re = ? Nu = ? (reference the table number where the equation is obtained) H = ? Calculate the rate of heat transfer per unit length, q.

A stone is thrown vertically upward with an initial velocity of 20 m/s. Air resistance is...

A stone is thrown vertically upward with an initial velocity of 20 m/s. Air resistance is considered negligible. (1) At what time does it reach the peak? (2) What is the maximum height it reaches? (3) What is speed of the stone just before it hits the ground? The velocity of a 1-kg particle moving along the x axis changes from vi = -2m/s to vf = -5m/s in 3s. (1) What are the change in momentum and impulse for...

Air flows in a pipe under fully developed conditions with an average velocity of 1.25 m/s...

Air flows in a pipe under fully developed conditions with an average velocity of 1.25 m/s and a temperature of 16°C. The pipe’s inner diameter is 4 cm, and its length is 4 m. The first half of the pipe is kept at a constant wall temperature of 100°C. The second half of the pipe is subjected to a constant heat flux of 200 W. The properties of air at 80°C are ρ = 0.9994 kg/m3, k = 0.02953 W/m·K,...

Cold air at temperature of 10 C and velocity of 3 m/s is moving parallel to...

Cold air at temperature of 10 C and velocity of 3 m/s is moving parallel to a flat plate with the length of 6 m and surface temperature of 75 C. A) Find the transition location on the plate and the heat loss from the plate. B) Repeat part (A) for water at the same velocity and temperature. The flat plate is made from copper.

Question