Applying a variable geometry ejector in a solar ejector refrigeration system

• Tipo: Artigo em Revista Científica Internacional
• Data: 2020

Autores

Vu Van Nguyen (Autor) Outra; Szabolcs Varga (Autor) Outra; João Soares (Autor) Outra; Vaclav Dvorak (Autor) Outra; Armando C. Oliveira (Autor) FEUP

Revista

Título: International Journal of Refrigeration

Vol. 113

Páginas: 187-195

ISSN: 0140-7007

Editora: Elsevier

Indexação

ISI Web of Knowledge - 0 Citações

ISI Web of Science

Scopus - 8 Citações

Outras Informações

ID Authenticus: P-00R-KH9

DOI: 10.1016/j.ijrefrig.2020.01.018

Abstract (EN): This paper presents an experimental study of the influence of a variable geometry ejector (VGE) design on the performance of a small-scale, 1.5 kW nominal capacity solar heat driven ejector air-conditioning system under real-life working conditions. Under variable operating conditions (e.g. solar radiation, ambient temperature) fixed geometry ejector performs poorly, therefore the objective of the present work was to prove the benefit of the VGE concept. In the experimentally tested VGE the area ratio through a movable spindle (SP) and the nozzle exit position (NXP) can be adjusted in order to respond to the operating conditions. The results showed very stable operation of the cooling cycle during the experiments. Both NXP, SP had considerable influences on the cooling cycle performance. An optimal NXP was identified, which did not change with various operating conditions. Similarly, SP also showed an optimum; however, the optimum point depended strongly on the operating conditions. The results clearly indicated the benefit of using the VGE design over the fixed geometry. COP improvement was as high as 24% with a maximum of 0.29 corresponding to a cooling capacity of 1.6 kW when compared to a fixed geometry ejector. The study also confirmed the importance of using a variable-speed pump in the ejector cycle. (C) 2020 The Authors. Published by Elsevier Ltd.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 9