Steam enters a counterflow heat exchanger operating at steady state at 0.06 MPa with a quality of 0.9 and exits at the same pressure as saturated liquid. The steam mass flow rate is 1.3 kg/min. A separate stream of air with a mass flow rate of 100 kg/min enters at 30oC and exits at 60oC. The ideal gas model with cp = 1.005 kJ/kg·K can be assumed for air. Kinetic and potential energy effects are negligible. Determine the temperature of the entering steam, in oC. For the overall heat exchanger as the control volume, what is the rate of heat transfer, in kW.

Explanation:

a) Term of entering steam will be Tsaturated of corresponding pressure

b)

the equation above shows how temperature f, measured in degrees fahrenheit, relates to a temperature c, measured in degrees celsius. based on the equation, which of the following must be true?

a temperature increase of 1 degree fahrenheit is equivalent to a temperature increase of

5

9

degree celsius.

a temperature increase of 1 degree celsius is equivalent to a temperature increase of 1.8 degrees fahrenheit.

a temperature increase of

5

9

degree fahrenheit is equivalent to a temperature increase of 1 degree celsius.

a) i only

b) ii only

c) iii only

d) i and ii only

answer:

explanation: