Question

**A plate of length 30 mm in the direction of the flow, a
width of 45 mm and thickness of 1mm, has a surface temperature of
78 ^{o}C is placed in a stream of air at a temperature of
30^{o}C and velocity of 3.5m/s . Calculate:**

**The heat loss from the top and bottom of the plate****The heat loss from a cylinder 5cm long and has the same volume as the plate and placed across the flow.**

**for air:** **ν****=
18.4****×****10 ^{-6}
m^{2}/s, Pr = 0.704, k = 0.0282
W/m**

Answer #1

there is a plate with 2ft width, 4ft length and 130°F
of the surface temperature. awater with 50°F of temperature flows
on this plate with 9ft/s velocity. Calculate the average heat
transfer coefficient and the convective heat loss in this plate.
For the calculation please use the following constant
properties.
heat conductivity(k)=0.36 Btu/(hr ft °F)
viscosity=5.14×10^(-4) lbm/(ft s)
density=62.11 lbm/(ft^(3))
Pr=5.12
Nu=0.036×Pr^(1/3)×Re^(2/3):laminar flow
Nu=0.036×Pr^(1/3)×(Re^(0.8)-23200):turbulent flow

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Question 3
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