Jet impingement is commonly used to attain high local heat exchange coefficients in several industrial frameworks. Both cooling and heating air jets can be used, where precise and rapid thermal control is required. This paper focuses on the air impingement cooling of cylindrical foods, the use of which has been devised and analyzed numerically during the initial stage of cooling/chilling operations. Results include the temperature distributions within the food and at its surface, as well as the associated flow field due to the jet–food interaction. Results have also been compared with available literature data and with classical heat transfer solutions. The local, time-dependent Nusselt number distribution in jet impingement cooling has been shown to be strongly dependent upon the conjugate effect, i.e. the heat transfer rate is altered by the conduction in the food, which is neglected in the associated studies available so far. Slowest Cooling Zones (SCZs) have also been found to lie off-center, depending upon the given thermal boundary conditions. The knowledge of transient temperature distributions within the processed food and related local heat transfer is important in cold treatment of foods, in order to achieve the desired system performance in the most efficient manner.

Analysis of food cooling by jet impingement, including inherent conduction

DE BONIS, MARIA VALERIA;RUOCCO, Gianpaolo
2007-01-01

Abstract

Jet impingement is commonly used to attain high local heat exchange coefficients in several industrial frameworks. Both cooling and heating air jets can be used, where precise and rapid thermal control is required. This paper focuses on the air impingement cooling of cylindrical foods, the use of which has been devised and analyzed numerically during the initial stage of cooling/chilling operations. Results include the temperature distributions within the food and at its surface, as well as the associated flow field due to the jet–food interaction. Results have also been compared with available literature data and with classical heat transfer solutions. The local, time-dependent Nusselt number distribution in jet impingement cooling has been shown to be strongly dependent upon the conjugate effect, i.e. the heat transfer rate is altered by the conduction in the food, which is neglected in the associated studies available so far. Slowest Cooling Zones (SCZs) have also been found to lie off-center, depending upon the given thermal boundary conditions. The knowledge of transient temperature distributions within the processed food and related local heat transfer is important in cold treatment of foods, in order to achieve the desired system performance in the most efficient manner.
2007
File in questo prodotto:
File Dimensione Formato  
JFOE2_07.pdf

non disponibili

Tipologia: Documento in Post-print
Licenza: DRM non definito
Dimensione 1.03 MB
Formato Adobe PDF
1.03 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11563/4663
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 31
  • ???jsp.display-item.citation.isi??? 23
social impact