Question

Question Completion Status: [CLO-4) Consider the 2-shell pass and 4-tube passes heat exchanger shown in the fure, cold water enters the tube at 10 °C and leaves at 70°C. Hotoletters the shell. The mass flow rate of water is 5 kg/s and of oil is 20 kg/s. if needed, you may take the specific heat Cp of liquid water to be 4.18 kuand of the oil is 20 kk.. Shell-side fluid Out Tube Image 016-new.pdf side fluid le Our The effectiveness of this heat exchanger is???? 779 a b. 809 70% C d. 759 85 e.

Answer 1

Given Temp of cold water at inlet = 10°c = Tc. Temp of cold watch at outlet = 70°C = Tez Temp of hot oil at intet = 90°C Thi lose Temp of hot oil at exit = The = 2. In heat exchanger Heat Heat gain Qoil Qwota -> mala [Thy - The] = Mele [Tea -> 20x 2 x [90-Tn] = 5x 4.18[70-10] - 90 - The 5x4.18 [60 31.35 Teil] 20 x2 Th₂ = 90-31-35 58.65°C mn mass mc- flow rate of oil = 20 kgls mass flow note of watu=s slegls che specific heat of oil = 2 kJ/kg'c specific head of watu Heat copacity note (= mac I low note Cc = 4.18 kJ/legic m mass с 2 heat capacity

Effectiveness of heat exchange Qact amox Tui Qact - Much (Tn, - Tz)= macel Ten Qmon = Emin [In, - Tes Cmin minimum heat capacity note The fluid having capacity rote ondergoes lange temp vaniation Note! min heat Head Hene Tempucture variation by hot all = Thi - The = 90-58.65 - 31.35Ć Temperature voniction by Cold Wote = Tez - Te, a 70-10 60°c variction is for The lange temp cold wota . Cmin = тех се Qmax = AXE Metce [Ini - Te,

Qact= - х = те се сте - те ) mece С 2- те, ) me. CTh, - те ) Тc, - Те, — Th, - Т., — 30 - 1 0 6 о Чо - 10 - о: 15 И = 7s /. Ке The effectiveness heat the given the volue exchange founded і 754 the conect option is d. — and а T