This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: 650:351 Thermodynamics Doyle Knight Department of Mechanical and Aerospace Engineering Rutgers  The State University of New Jersey New Brunswick, NJ USA Tel: 732 445 4464 · Email: [email protected] Office hours: Tuesday and Friday, 9:00 am to 11:30 am and by appointment Midterm Examination Problem No. 1 A cylinder is filled with 1 kg of R12 at 1.5 MPa and 100 ◦ C. The refrigerant is cooled to 25 ◦ C. Find the heat transfer 1 Q 2 and work done 1 W 2 . Solution The work done is 1 W 2 = integraldisplay 2 1 pdV At p = 1 . 5 MPa, the temperature for saturated vapor is 59.2 ◦ C. Since T 1 = 100 ◦ C, State 1 is superheated vapor. At T = 25 ◦ C, the pressure for saturated vapor is p 2 sat = 651 . 6 kPa. It is therefore evident that p 2 < 1 . 5 MPa (consider p − v diagram). Therefore, the piston must hit the stops, and State 2 is saturated liquidvapor or a compressed liquid. 650:351 Thermodynamics Page 1 Midterm Examination The pressure in the R12 remains constant and equal to 1.5 MPa as the piston descends. As theThe pressure in the R12 remains constant and equal to 1....
View
Full
Document
This note was uploaded on 04/07/2008 for the course MECH 201 taught by Professor Morgan during the Spring '08 term at Rutgers.
 Spring '08
 Morgan

Click to edit the document details