Optimal efficiency-power tradeoff for an air motor/compressor with volume varying heat transfer capability

Andrew T. Rice, Perry Y. Li

Research output: Chapter in Book/Report/Conference proceedingConference contribution

13 Scopus citations

Abstract

This paper presents the pressure-volume trajectories that yield the optimal tradeoff between efficiency and power during the compression and expansion of air. These results could benefit applications such as compressed air energy storage where both high efficiency and power density are required. Earlier work established solutions for the simple case in which hA, the product of the heat transfer coefficient and heat transfer surface area, is constant. This paper extends that analysis by allowing hA to vary with air volume. Solutions to the constrained, nonlinear optimization problem are developed utilizing the method of Lagrange multipliers and Karush-Kuhn-Tucker (KKT) conditions. It is found that the optimal trajectory takes the form "fast-slow-fast" where the fast stages are adiabatic and the temperature change during the slow stage is proportional to the inverse root of the hA product. A case study predicts a 60% improvement in power over the constant-hA solution when both trajectories are run at 90% efficiency and hA = hA(V). Compared to linear-and sinusoidal-shaped trajectories, also at 90% efficiency, power gains are expected to be in the range of 500-1500%.

Original languageEnglish (US)
Title of host publicationASME 2011 Dynamic Systems and Control Conference and Bath/ASME Symposium on Fluid Power and Motion Control, DSCC 2011
Pages145-152
Number of pages8
DOIs
StatePublished - 2011
EventASME 2011 Dynamic Systems and Control Conference and Bath/ASME Symposium on Fluid Power and Motion Control, DSCC 2011 - Arlington, VA, United States
Duration: Oct 31 2011Nov 2 2011

Publication series

NameASME 2011 Dynamic Systems and Control Conference and Bath/ASME Symposium on Fluid Power and Motion Control, DSCC 2011
Volume1

Other

OtherASME 2011 Dynamic Systems and Control Conference and Bath/ASME Symposium on Fluid Power and Motion Control, DSCC 2011
Country/TerritoryUnited States
CityArlington, VA
Period10/31/1111/2/11

Fingerprint

Dive into the research topics of 'Optimal efficiency-power tradeoff for an air motor/compressor with volume varying heat transfer capability'. Together they form a unique fingerprint.

Cite this