Question

Water (specific heat = 4 k J/kg K) enters a cross flow exchanger (both fluids unmixed) at 15 degree Celsius and flows at the rate of 7.5 kg/s. It cools air (C P = 1 k J/kg K) flowing at the rate of 10 kg/s from an inlet temperature of 120 degree Celsius. For an overall heat transfer coefficient of 780 k J/m2 hr degree and the surface area is 240 m2, determine the NTU a) 1.2 b) 8.2 c) 6.2 d) 5.2

Name: water specific heat 4 k jkg k enters a cross flow exchanger both fluids unmixed at 15 degree celsius and flows at the rate of 75 kgs it cools air c p 1 k jkg k flowing at the rate of 10 kgs from an in
Uploaded: 2022-02-28T08:46:08-08:00
Duration: 3 min 31 s
Channel: Kajal Raghubanshi
Description: water specific heat 4 k jkg k enters a cross flow exchanger both fluids unmixed at 15 degree celsius and flows at the rate of 75 kgs it cools air c p 1 k jkg k flowing at the rate of 10 kgs from an in

          Water (specific heat = 4 k J/kg K) enters a cross flow exchanger (both fluids unmixed) at 15 degree Celsius and flows at the rate of 7.5 kg/s. It cools air (C P = 1 k J/kg K) flowing at the rate of 10 kg/s from an inlet temperature of 120 degree Celsius. For an overall heat transfer coefficient of 780 k J/m2 hr degree and the surface area is 240 m2, determine the NTU
a) 1.2
b) 8.2
c) 6.2
d) 5.2

Added by John K.

University Physics with Modern Physics

Hugh D. Young 14th Edition

Instant Answer

Solved by Expert Kajal Raghubanshi

02/28/2022

Step 1

• Water: mass flow rate = 7.5 kg/s, specific heat = 4 kJ/kg·K, so its heat capacity (Cwater) = 7.5 × 4 = 30 kJ/s·K. • Air: mass flow rate = 10 kg/s, specific heat = 1 kJ/kg·K, so its heat capacity (Cair) = 10 × 1 = 10 kJ/s·K. Show more…

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Water (specific heat = 4 k J/kg K) enters a cross flow exchanger (both fluids unmixed) at 15 degree Celsius and flows at the rate of 7.5 kg/s. It cools air (C P = 1 k J/kg K) flowing at the rate of 10 kg/s from an inlet temperature of 120 degree Celsius. For an overall heat transfer coefficient of 780 k J/m2 hr degree and the surface area is 240 m2, determine the NTU a) 1.2 b) 8.2 c) 6.2 d) 5.2