Share

IIR document

Analysis on expansion and phase change process of CO2 expander.

Author(s) : AN Q., MA Y., LI M., et al.

Summary

Since the expansion process is the key problem to influencing CO2 expander performance, in the present work, the effect of pressure, temperature and depressurization rate on expanding process was investigated. Furthermore, according to test P-V diagram of CO2 expander and visualization experiment of CO2 bubble nucleation, three distinct stages of expansion and phase change for CO2 expanding process were defined. These three stages are termed as initially prepared, free and limited expansion, and that are controlled by the bubble nucleation rate. The first stage mainly includes the transfer of energy fluctuation due to pressure wave transmission, the pressure and specific volume remains basically constant. Bubble nucleation is assumed to occur in the free expansion stage due to the pressure difference, but volume changes very little. The third stage is termed the limited expansion stage, most of bubble volume and expanding work takes place in the third stage due to chemical potential difference, yet the pressure changes become small. The results of theoretical analysis and visualization experiment observation revealed that the size of bubble decreases and their nucleation population increases with pressure increase, or decrease of temperature, and increase of the depressurization rate. Expanding work recovery is correlated by combining nucleation and bubbles growth in supersaturated CO2.

Available documents

Format PDF

Pages: 2008-2

Available

  • Public price

    20 €

  • Member price*

    Free

* Best rate depending on membership category (see the detailed benefits of individual and corporate memberships).

Details

  • Original title: Analysis on expansion and phase change process of CO2 expander.
  • Record ID : 2010-1371
  • Languages: English
  • Source: 8th IIR-Gustav Lorentzen Conference on Natural Working Fluids (GL2008)
  • Publication date: 2008/09/07

Links


See other articles from the proceedings (132)
See the conference proceedings

Indexing