To main content

Development and performance mapping of a multi-ejector expansion work recovery pack for R744 vapour compression units

Abstract

A multi-ejector expansion pack, intended as a substitute for a standard high-pressure electronic expansion valve (HPV), was designed, manufactured and experimentally investigated. Four different ejector cartridges were sized to enable a discrete opening characteristic with a binary profile for a parallel-compression R744 system. The system is rated for 70 kW at a 35 °C gas cooler outlet temperature and a -3 °C evaporation temperature. High values of ejector efficiency, exceeding 0.3 over a broad operation range, were recorded for all four of the cartridges tested under vapour compression conditions. The applicability of the multi-ejector pack as a main flashing device was verified experimentally. Similar profiles of the discharge pressure control error were recorded for both alternative options: expansion purely in the HPV vs. HPV-assisted expansion in the multi-ejector pack.

Category

Academic article

Client

  • Research Council of Norway (RCN) / 244009

Language

English

Author(s)

  • Krzysztof Banasiak
  • Armin Hafner
  • Ekaterini E. Kriezi
  • Kenneth B. Madsen
  • Michael Birkelund
  • Kristian Fredslund
  • Rickard Olsson

Affiliation

  • SINTEF Energy Research / Termisk energi
  • Denmark

Year

2015

Published in

International journal of refrigeration

ISSN

0140-7007

Publisher

Elsevier

Volume

57

Page(s)

265 - 276

View this publication at Cristin