Question

Question 13 (5 points) We want to increase the air temperature from 14.4°C to 30°C by passing over a bank of brass tubes inside which steam at 100°C is condensing Chci = 5680 tubes (L=0.61 m, D.-1.27 cm, & wall thickness d=0.125 cm) are arranged in-line in a square pattern with a pitch of 1.9 cm inside a rectangular shell (0.61 m wide, 38 cm high). If the total mass flow rate of air is 4 kg/s, calculate the following parameters. w m?' The Brass tubes 38 cm 0.61 m 1.9 cm 1.27 cm Air Steam 100°C SL + V, T. Row 1 Row 2 Row 3 (a) Estimate the maximum Reynolds number of the flow passing over the tube bundle. (choose the closest answer)

Write the solution of the maximum Reynolds number of the flow passing over the tube bundle here.

(b) Estimate the average Nusselt number of the flow passing over the tube bundle. (choose the closest answer)

Write the solution of the average Nusselt number of the flow passing over the tube bundle here

(c) Estimate the number of required transverse rows. (choose the closest answer)

Write the solution of the number of required transverse rows here.

Answer 1

vo - 0,00KV&A 5 + 2.8985x16 1.277ty to XN 5-3 1.27 1.27-2X0.125 5680 2. 1921 X10-4 105 105 3)). 7707 +1 2771N 21.9207 + 1.277IN + 289. 85 U. Ao stem Total heat transfer (2) 105 TX DO XL XNX X 311.7707 +1.277IN 77.54 188716 2184 N 311.7707 +1.27HIN Now, e eap L- (- exp(-o 100 1000 Ts :) Ts To TID. NĪ, To - Ti PVN, ST CP exp TX 1.27 : NX 345 1.1838% 14.577X MX 1.a 1007 -) Bo -0.0417N 2 Ts - 14.4 NG Now, 6 = hoix (100 - Ts) & ITDi XLYN 5680 m (100 - Ts) * lx (1.27 - 2x0.125) *0.61XN 11.027N * (100-Ts) 3 from ① & ② 188716 2184 N 111.027N X1100-Ts) 311.7707 + 1.27HN 1700 = 3454 (311.77+ 1.277N)X1100-Ts)- Suppose NL =10 N/N = 10: from ② Ts 60.15 (NLYN = N) not possible From 4 NL = 2 5 Ts = 97.29°c 97.29°e, No 247.27 : Ng= 49.45720 Neo
Even after 4 hours of hard work , Nt could not be found. Please be considerate before giving thumbs down. Thanks.