# Midterm_II_2002_w_Answers_ - MEAM 203 FALL 2002 THERMO...

This preview shows pages 1–2. Sign up to view the full content.

MEAM 203 FALL 2002 THERMO - MIDTERM II Closed books. Answer all three questions. Write clearly! Explain all steps. Answers without clear explanation will be discounted. GOOD LUCK . (30%) 1. In a counter flow heat exchanger air is used to heat up water. Air enters the heat exchanger at 2 kg/s, 125 kPa, and 1000 K and leaves at 100kPa and 400 K. Water enters at 0.5 kg/s, 200kPa, 20C, and it leaves as liquid vapor mixture at 200kPa. (15 %) (A) What is the quality of the exiting steam? ( 5%) (B) What is the rate of change in the air entropy? (10%) (C) What is the total rate of entropy generation? Assume that the air is an ideal gas with temperature-independent specific heat Cp=1kJ/kg-K and R=0.287kJ/kg-K. The properties of the water are given below: Water: T=20C; p=200kPa; u=84kJ/kg; h=84kJ/kg; v=0.001m 3 /kg; s=0.3kJ/kg-K Saturated water at p=200kPa; u v =2530kJ/kg; h v =2707kJ/kg; s v =7.13kJ/kg-K; u l = 505kJ/kg; h l = 505kJ/kg; s l =1.53kJ/kg-K; (30%) 2. An adiabatic tank of volume V is initially evacuated. The tank is connected through a valve to a line that carries an ideal gas at pressure p L and temperature T

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

## This test prep was uploaded on 04/10/2008 for the course MEAM 203 taught by Professor Bau during the Spring '08 term at UPenn.

### Page1 / 3

Midterm_II_2002_w_Answers_ - MEAM 203 FALL 2002 THERMO...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online