Oil entrainment in vertical refrigerant piping

Kesim S., Albayrak K., Ileri A.

INTERNATIONAL JOURNAL OF REFRIGERATION-REVUE INTERNATIONALE DU FROID, cilt.23, sa.8, ss.626-631, 2000 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 23 Sayı: 8
  • Basım Tarihi: 2000
  • Doi Numarası: 10.1016/s0140-7007(99)00085-7
  • Dergi Adı: INTERNATIONAL JOURNAL OF REFRIGERATION-REVUE INTERNATIONALE DU FROID
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.626-631
  • Anahtar Kelimeler: refrigerating circuit, piping, vertical tube, oil return, refrigerant, vapour, speed, calculation
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

The aim of this study is to investigate the required refrigerant speed, hence minimum refrigeration load, for carrying the lubricating oil up in vertical sections of refrigerant lines. It is assumed that the downward flow of the thin oil layer over the inner surface of the riser due to gravity is to be balanced with the upward flow of the oil film due to the shear force created by the upward flow of the refrigerant vapor. Velocities are converted to refrigeration capacities by considering a saturated cycle between specified condenser and evaporator pressures. General relationships thus developed are enumerated for R134a by preparing minimum capacity tables for copper suction and discharge risers. (C) 2000 Elsevier Science Ltd and IIR. All rights reserved.