An insulated steam pipe is used to transport high-temperature steam from one building to another. The pipe has a diamete

[answerhappygod]

An Insulated Steam Pipe Is Used To Transport High Temperature Steam From One Building To Another The Pipe Has A Diamete 1 (83.68 KiB) Viewed 47 times

An insulated steam pipe is used to transport high-temperature steam from one building to another. The pipe has a diameter of 500 mm, a surface temperature of 164 °C and is exposed to ambient air at -10 °C. The pipe is subjected to an external forced convection as the air moves in a cross-flow over the pipe at a speed of 5 m/s (see figure below). a. What are the main assumptions? b. What is the heat loss per unit length of pipe without insulation? c. What is the heat loss per unit length of pipe if the insulation thickness is 10 mm? Air V=5 m/s T. -10°C 78; = 150 °C Insulation k, = 0.026 W/m-K D = 500 mm -Tso Steam 056s 50 mm 14.10 - 10% Q.10 PY Thermophysical Properties of Air at Atmospheric Pressure T P k. 10 (K) (kg/m) (kJ/kg-K) (Ns/m) (mºls) (W/ mK) (m/s) 100 3.5562 1.032 71.1 200 9.34 254 150 2.3364 1.012 103.4 4.426 13.8 5.84 200 1.7458 1.007 132.5 7590 18.1 10.3 250 1.3947 1.006 159.6 11.44 22.3 15.9 300 1.1614 1.007 184.6 15.89 26.3 22.5 350 0.9950 1.009 208.2 20.92 30.0 299 400 0.8711 1.014 230.1 26.41 33.8 38.3 450 0.7740 1.021 250.7 3239 373 472 500 0.0964 1.030 270.1 38.79 40.7 56.7 SSO 0.6329 1.040 288.4 45 57 43.9 66.7 For gases at atmospheric pressure, the ideal gas model applies, and p-p/RT 0.786 0.758 0.737 0.720 0.707 0.700 0.690 0.686 0.684 0.683 Convection Heat Transfer Correlations for External Flow Correlation Range of Applicability Flow hD 0.62 Rebp/1/3 S/2 4/5 Cylinder Nud 0.3+ Red 282.000) Rep Pr > 0.2 1/4 | [1+(01/a)" ME k 2019