Thermodynamics HW Solutions 630

# Thermodynamics HW Solutions 630 - Chapter 7 External Forced...

This preview shows page 1. Sign up to view the full content.

This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Chapter 7 External Forced Convection 7-100 Steam is flowing in a stainless steel pipe while air is flowing across the pipe. The rate of heat loss from the steam per unit length of the pipe is to be determined. Assumptions 1 Steady operating conditions exist. 2 Air is an ideal gas with constant properties. 3 The pressure of air is 1 atm. Properties Assuming a film temperature of 10 ° C, the properties of air are (Table A-15) 7336 . Pr and /s, m 10 426 . 1 C, W/m. 02439 . 2-5 = × = υ ° = k Analysis The outer diameter of insulated pipe is D o = 4.6+2 × 3.5=11.6 cm = 0.116 m. The Reynolds number is 4 2 5 10 254 . 3 /s m 10 426 . 1 m) m/s)(0.116 (4 Re × = × = υ = − ∞ o D V The Nusselt number for flow across a cylinder is determined from ( ) [ ] ( ) [ ] . 107 000 , 282 10 254 . 3 1 7336 . / 4 . 1 ) 7336 . ( ) 10 254 . 3 ( 62 . 3 . 000 , 282 Re 1 Pr / 4 . 1 Pr Re 62 . 3 . 5 / 4 8 / 5 4 4 / 1 3 / 2 3 / 1 5 . 4 5 / 4 8 / 5 4 / 1 3 / 2 3 / 1 5 ....
View Full Document

## This note was uploaded on 01/22/2012 for the course PHY 4803 taught by Professor Dr.danielarenas during the Fall '10 term at UNF.

Ask a homework question - tutors are online