Evaluation of Improvements to Brayton Cycle Performance.

Abstract

This study addresses the problem of finding an energy conversion method to take advantage of the high maximum cycle temperatures achieved with solar central receivers. Most current practice is to use steam-based heat engines with solar receivers but these Rankine cycles cannot operate at the higher possible temperatures. Derivatives of gas-based Brayton cycles are considered to take advantage of the expected increased cycle performance of higher temperatures. Computer modelling was done to examine the effect of maximum temperature on efficiency of two Brayton cycle derivatives and a simple Brayton cycle (GT). The modified Brayton cycles include a combination of intercooling, regeneration, and reheat (IGT) and a Brayton cycle with steam injection (STIG). The turbine inlet temperature, the steam-to-air injection mass ratio (for the STIG), and the compression pressure ratios were treated as parameters in the analysis. Both First Law and Second Law efficiencies were examined. Efficiencies were highest for the IGT followed by the STIG and GT, respectively. Considerable improvements in specific work output were demonstrated by the STIG over both the IGT and GT systems. First and Second law analyses show a gradual increase of efficiency with turbine inlet temperature with diminishing returns at higher temperatures. Keywords: Solar power. (Theses)

Open PDF

Document Details

Document Type
Technical Report
Publication Date
May 29, 1986
Accession Number
ADA169018

Entities

People

  • Michael A. Spasyk

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Masses
  • Combustion
  • Compression Ratio
  • Computers
  • Cycles
  • Energy
  • Engines
  • Exhaust Gases
  • Gas Turbines
  • Heat Energy
  • Heat Engines
  • Heat Recovery
  • Heat Transfer
  • Materials
  • Solar Energy
  • Thermodynamics
  • Turbine Blades

Readers

  • Calculus or Mathematical Analysis
  • Electrical Engineering
  • Thermal Physics or Thermal Science.