Refrigerant 134a flows in a 5-m long square duct that is located in a warehouse. One side of the square duct is 4 cm and surface temperature is -10 0C. Emissivity of the duct surface is 0.85. Air (ρ=1.2 kg/m3, cp=1 kJ/kgK, k=0.03 W/mK, ν=2x10-5 m2/s, Pr=0.7) at 30 0C is blown over the duct. Temperature of the warehouse walls is 60 0C. What is the required air velocity to transfer 1 kW of heat to the duct?a.6 m/sb.4 m/sc.2 m/sd.5 m/se.3 m/s Refrigerant 134a flows in a 5-m long square duct that is located in a warehouse. One side of the square duct is 4 cm and surface temperature is -10°C. Emissivity of the duct surface is 0.85. Air (p=1.2 kg/m³, c,=1 kJ/kgK, k=0.03 W/mK, v=2x10-5 m2/s, Pr=0.7) at 30 °C is blown over the duct. Temperatureof the warehouse walls is 60 °C. What is the required air velocity to transfer 1 kW of heat to the duct?O a. 6 m/sO b. 4 m/sO c. 2 m/sO d. 5 m/sО е. 3 m/s

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Refrigerant 134a flows in a 5-m long square duct that is located in a warehouse. One side of the square duct is 4 cm and surface temperature is -10 0C. Emissivity of the duct surface is 0.85. Air (ρ=1.2 kg/m3, cp=1 kJ/kgK, k=0.03 W/mK, ν=2x10-5 m2/s, Pr=0.7) at 30 0C is blown over the duct. Temperature of the warehouse walls is 60 0C. What is the required air velocity to transfer 1 kW of heat to the duct? a.

Refrigerant 134a flows in a 5-m long square duct that is located in a warehouse. One side of the square duct is 4 cm and surface temperature is -10 0C. Emissivity of the duct surface is 0.85. Air (ρ=1.2 kg/m3, cp=1 kJ/kgK, k=0.03 W/mK, ν=2x10-5 m2/s, Pr=0.7) at 30 0C is blown over the duct. Temperature of the warehouse walls is 60 0C. What is the required air velocity to transfer 1 kW of heat to the duct? a.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.38P

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