Water at 20°C enters a 1.91 cm ID, 57 cm long tube at a flow rater of 3 gm/s. The tube wall is maintained at 30°C. Determine the water outlet temperature. What error in the water temperature results if natural convection effects are neglected? 

GIVEN

• Water flowing through a tube
• Entering water temperature (T_b,in) = 20°C
• Tube inside diameter (D) = 1.91 cm = 0.0191 m
• Tube length (L) = 57 cm = 0.57 m
• Mass flow rate (m) = 3 gm/s = 0.003 kg/s
• Tube wall surface temperature (T_s) = 30°C

ASSUMPTIONS

• Steady state
• Tube temperature is uniform and constant
• The tube is horizontal

Transcribed Image Text:

T= 30°C D-1.91 cm Water Taout =? Tbn = 20°C m- 39 m/s L- 57 cm