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mm, electrical resistance per unit length An electrical transmission line (diameter: D=5 r=0.002 Ω/m) carries an electric current (1-100 A), dissipating an electrical power per unit length inr. On a windy day, the line is subjected to air flow (air temperature: T. -10C, air velocity V 50 km/hr) T, 10°C V 50 km/hr T, =? 1 -100 A air elec electrical line We would like to determine the surface temperature of the wire, T, under such conditions. Since T, is unknown but is needed to estimate the air properties, an terative procedure must be implemented. a) (4 pts) By considering an energy balance on the electrical line, develop an expression for the temperature T, in terms of r, 1,D,T,h, where h is the average convection coefficient over the cylinder. Show that T, =10+ 1273.24
b) (2.5 pts) Assuming an initial guess T, 70°C and using the table conductivity k, kinematic viscosity u and Prandtl number Pr thermal using the table below, determine the viscosity and Pr of the air at an appropriate Kinematic Number Dynamic Viscosity Diffusivity k, W/m-H 0.02364 0.02401 0.02439 0.7362 1.338 x 10 1.382 × 10。 1.426x10 1.470 × 1.516× 10-s 0.7350 0.7336 1 818 × 10 1.880 × 10-5 1.944 x 10-5 1.729 x 10- 1.754 × 10-5 1.778 × 10-s 1.802 × 10-s 1.825× 10-s o-5 1.246 1.225 10 0.7323 0.7309 1007 2.009 10 s 2.074 × 10-s 2.141x 10-5 1849 x 10 1007 1007 1007 1007 1.562 x 10- 0.02551 0.02588 0.02625 О.7282 2.277 × 10 s 1.895 × 10 ° 1.655 x 10 ° 0.7268 2.346 x 10- 1.918 x 10 1.702 x 10 0.7255 1.608 x10s 1.145 2.208 x 105 1.872 x 105 2.416 x 10 1.941 10 1.750 x 10 0.7241 0.7228 0.02735 0.02808 2.487 × 10 2.632 × 10-s 1.963 x 1 1.798 x 10 2.008 x 10-5 1007 1.896 × 10 Eilim temperature:o2loo Air properties: (2 pts) The convection correlation for cylinder in cross flow is given by the Churchill and Bernstein correlation: c) 0.3+0.62 Rel? pr/a I+(0(282,000 which is valid when Rep Prz0.2. Is this correlation valid in the present situation?
d) (2 pts) Determine the surface temperature T o) (7.5 pts) Perform one more teration: answer questions in parts b), @) and d) by considering the new temperature T, obtained above. Does the process seem to converge? Updated film temperature Prandt Number Thermal Dynamie Viscosity Specific Temp Densty Heat Conductivity Diffusivity Viscosity Pr 0 02364 İ818 x 10-s 1.729xio-s 1.338 x 10., 0.7362 0.02401 1880 x 10- 1.754 10 1.382 x 10-s 0.7350 0.02439 1.944×10-s 1.778×10-5 1.426×10-4 0.7336 0.02476 2.009 x 10-1802x10s1470 x 100.7323 0.02514 2.074 × 10.5 1X5 × 10 s 1.516 x 10 s 0.7309 1.292 1006 10 15 20 1.246 1.225 1.204 1007 1007 Updated air properties (no need to interpolate, take the closest temperature value in the table): Convergence conclusion
Please show claer solve for ( a,c,d,e ) of this qustion.
engineering   Mechanical-Engineering   
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a) The mte ated the electrical is 8-R As 40℃ LA Properties 415 Re 40g 0-1 61 518 ガ :05+062(408006755-7255T(箱 hこ33:35×0.02662 0.006 rmg correlation is vold in the Yetsert situation

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Please show claer solve for ( a,c,d,e ) of this qustion. mm, electrical resistance per unit...
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