1 / 13

ES 202 Fluid and Thermal Systems Lecture 15: Properties in Two-Phase Region (1/16/2003)

ES 202 Fluid and Thermal Systems Lecture 15: Properties in Two-Phase Region (1/16/2003). Assignments. Homework: 3-28, 3-29 in Cengel & Turner Reading assignment Tables A-4 to A-14 in Cengel & Turner. Announcements. More on Lab 2 write-up due tomorrow no length limit

lidiam
Download Presentation

ES 202 Fluid and Thermal Systems Lecture 15: Properties in Two-Phase Region (1/16/2003)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. ES 202Fluid and Thermal SystemsLecture 15:Properties in Two-Phase Region(1/16/2003)

  2. Assignments • Homework: • 3-28, 3-29 in Cengel & Turner • Reading assignment • Tables A-4 to A-14 in Cengel & Turner ES 202 Fluid & Thermal Systems

  3. Announcements • More on Lab 2 write-up • due tomorrow • no length limit • Contents: water wall, Torricelli experiment, pipe friction • data interpretation • Problem session today at 7 pm in O167 • show outline • Bring your text book to class next Monday ES 202 Fluid & Thermal Systems

  4. Road Map of Lecture 15 • Review of Lecture 14 • Phase diagram • familiarity with terminology • familiarity with various regions • Focus on two-phase dome • dependency between temperature and pressure • new property: quality • Exercise on properties table ES 202 Fluid & Thermal Systems

  5. Review of Lecture 14 • What is the State Principle? • Identify the regions on the P-v, T-v planes ES 202 Fluid & Thermal Systems

  6. Working with P-v, T-v Diagrams • Compressed liquid • Superheated vapor • The two-phase (vapor) dome • Saturated liquid line • Saturated vapor line • Critical point • Trace a constant pressure curve on the T-v diagram • how it relates to the ideal gas model • in what direction is pressure increasing? • Trace a constant temperature curve on the P-v diagram • how it relates to the ideal gas model • in what direction is temperature increasing? ES 202 Fluid & Thermal Systems

  7. increasing direction of pressure constant pressure line T-v Diagram Critical Point Compressed liquid Superheated vapor Two-phase dome Saturated vapor line Saturated liquid line ES 202 Fluid & Thermal Systems

  8. increasing direction of temperature constant temperature line P-v Diagram Critical Point Superheated vapor Compressed liquid Two-phase dome Saturated liquid line Saturated vapor line ES 202 Fluid & Thermal Systems

  9. vapor liquid Illustration of Two-Phase Mixture • Imagine a heating process in a cylinder with a constant weight as a lid (closed system; control mass) } mixture of liquid and vapor heating ES 202 Fluid & Thermal Systems

  10. The Two-Phase Dome • A mixture of liquid and vapor • Temperature and pressure are NOT independent in the two-phase dome • one specifies the other (reference to P-v diagram, table) • example: boiling point of water at different altitudes • need another independent property to completely specify the state: • concept of quality ES 202 Fluid & Thermal Systems

  11. g f d D Introducing Quality • Definition: mass fraction of vapor in the mixture • Geometric interpretation: • Serves as another independent thermodynamic variable in the “Two-phase dome” ES 202 Fluid & Thermal Systems

  12. Significance of Quality • Define properties in the “Two-Phase dome” • For example: • extensive property: internal energy • using quality, its intensive counterpart can be expressed as a mass-weighted average of the saturated liquid and saturated vapor values • internal energy in the above example can be replaced by any other extensive property, e.g. enthalpy, volume, entropy, etc. ES 202 Fluid & Thermal Systems

  13. Saturated Temperature, Pressure Tables • Show saturated water – temperature table (Table A-4) • indicate dependency between temperature and saturation pressure • indicate saturated liquid and saturated vapor values for various intensive properties • Show saturated water – pressure table (Table A-5) • indicate dependency between pressure and saturation temperature • indicate saturated liquid and saturated vapor values for various intensive properties ES 202 Fluid & Thermal Systems

More Related