Engineering, 05.12.2019 04:31 sydneyrasmussen
Along aluminum wire of diameter 3 mm is extruded at a temperature of 280°c. the wire is subjected to cross air flow at 20°c at a velocity of 5.50 m/s. determine the rate of heat transfer from the wire to the air per meter length when it is first exposed to the air. the properties of air at 1 atm and the film temperature of (ts + t[infinity])/2 = (280 + 20)/2 = 150°c are k = 0.03443 w/m·°c, ν = 2.860 × 10−5 m2/s, and pr = 0.70275.
Answers: 1
; kinematic viscosity 
; Prandtl number 
, the flow is said to be laminar.![Nu_{cyl}= 0.3 + \frac{0.62Re^{0.5}Pr^{\frac{1}{3}}}{[1+(\frac{0.4}{Pr})^{\frac{2}{3}}]^{\frac{1}{4}}}[1+(\frac{Re}{282000})^{\frac{5}{8}}]^{\frac{4}{5}}](/tpl/images/0404/0147/a8606.png)
![Nu_{cyl}= 0.3 + \frac{0.62(576.92)^{0.5}(0.70275)^{\frac{1}{3}}}{[1+(\frac{0.4}{(0.70275)})^{\frac{2}{3}}]^{\frac{1}{4}}}[1+(\frac{576.92}{282000})^{\frac{5}{8}}]^{\frac{4}{5}}\\\\=12.11](/tpl/images/0404/0147/5c60d.png)
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Along aluminum wire of diameter 3 mm is extruded at a temperature of 280°c. the wire is subjected to...
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