A flow of air with a temperature of 45 °C is flowing at a velocity of 3 m/s around a copper wire of 2.5 mm diameter. An
Posted: Tue Apr 26, 2022 4:05 pm
A flow of air with a temperature of 45 °C is flowing at a
velocity of 3 m/s around a copper wire of 2.5 mm diameter. An
electric current is passed through the wire to heat it until its
temperature is uniform Ti= 82 °C. Then the current is suspended and
the wire is observed to cool to 57 °C in 10 seconds.
a) In what regime is the fluid?
b) Calculate the Nusselt number using the Churchill
equation.
c) Calculate the convective coefficient of the air.
d) How much heat does the wire lose per meter of
length?
e) What would be the percentage error in the heat calculation if
the Nusselt number were obtained using the simplified equation?
Include diagram an hyphotesis
velocity of 3 m/s around a copper wire of 2.5 mm diameter. An
electric current is passed through the wire to heat it until its
temperature is uniform Ti= 82 °C. Then the current is suspended and
the wire is observed to cool to 57 °C in 10 seconds.
a) In what regime is the fluid?
b) Calculate the Nusselt number using the Churchill
equation.
c) Calculate the convective coefficient of the air.
d) How much heat does the wire lose per meter of
length?
e) What would be the percentage error in the heat calculation if
the Nusselt number were obtained using the simplified equation?
Include diagram an hyphotesis