Question

Q3- A tube is painted on the inside with naphthalene and has an inside diameter of 30 mm and a length of 1.10 m. Air at 31t k and an average pressure of 101.3XPa flows through this pipe at a velocity of 0.80 m/s. Assuming that the absolute pressure remains essentially constant, calculate the concentration of naphthalene 5.16 10 m/s at in the exit air. The P 75 Pa and DAn of naphthalene in air is 298 k and 101.3 kPa

Answer 1

Solution;

Given that;

Solution :- given That :- diameter 'Di = 30mm length :1.10m. Temperatuur Te 30k - Pai = 75 Pa DAB Napinalen in air is = 5.16*10 m2s. at temperature 98k. pressure p= 101.3 kpa Now. P= CRT ? Tn2 = - Donostian — by fick's law we are o calculating . also Jaz = - DAB I dy / RT dz (Or) Jaz = DAB ( Par- PA2) RT (Z₂-21) | where R is universal gas Constant R=.8314.35/ kg

we have all values substitute TAz = 5.16 x 16°x (101.3460° - 75) Jos = 8314.3 x 298 x 110 5.16xcomo (101.3x103-75 ) 831413 x 298 x 110 JA2 = 1.916 x 107 Jaz = - DAB. dca 1.916x1o * -5.16x160x60-C) 1.10 1.10X1.916 710 7 =( 5.16 x 100 1 , 0 - 40 ml) The required concentration of new the line in the exit air is 0.040 m/h Thank you