A small space heater is constructed of 1/2-in., 18-gauge brass tubes, 2 ft long. The tubes are arranged in equilateral, staggered triangles on 1 1/2-in. centers, four rows of 15 tubes each. A fan blows 2000 cfm of atmospheric pressure air at 70?F uniformly over the tubes (see sketch). Estimate:(a) Heat transfer rate(b) Exit temperature of the air(c) Rate of steam condensation, assuming that saturated steam at 2 psig inside the tubes as the heat source. State your assumptions. Work parts a, b, and c of this problem by two methods. First use the LMTD, which requires a trial-and-error or graphical solution then use the effectiveness methods.GIVENA small heater made of 4 rows of 15 tubes each as shown aboveTubes: 1/2 in., 18 gauge brassTube length (L) = 2 ft.Distance between tube centers (2 ST) = 1.5 in = 0.125 ftAir flow rate (V) = 2000 ft3/min = 120,000 ft3/hAir inlet temperature (Ta,in) = 70?FSaturated steam inside the tubes at pressure (ps) = 2 psig = 16.7 psiaDuct width (w) = 2ft

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3 Air 1.5" 24" Duct Wall 2.