Flow in a Forward-Feed Plate Evaporator Using Computational Fluid Dynamics | ||
| تحقیقات مهندسی صنایع غذایی | ||
| Article 7, Volume 14, Issue 4, January 0, Pages 87-104 PDF (1008.93 K) | ||
| Document Type: Research Paper | ||
| DOI: 10.22092/jaer.2014.100251 | ||
| Abstract | ||
| Concentration decreases the amount of waterin liquid food and increases shelf life. Several types of evaporators are used for concentration, thus, it is necessary to simulate the process before design to control efficiency. The flow of pomegranate juice was simulated in a forward-feed flat plate evaporator at concentrations of 18 to 50 Brix in a two-phase mixture model using computational fluid dynamics. The results show that a vacuum developed in the evaporator column causing a slight drop in pressure at the inlet. Temperature increased at high intensities at the flow entrance zone. The magnitude of the velocity of the vapor increased as the flow increased from the inlet toward the outlet of the evaporator. Radial velocity was at a maximum in the middle of the flow medium and decreased gradually toward the boundary layer. The volume fraction of the pomegranate juice decreased and the volume fraction of the steam increased gradually from the inlet toward the outlet of the evaporator. This model can be applied for other liquids, but it is first necessary to define the thermo-physical properties of the liquid at different concentrations. | ||
| Keywords | ||
| Computational fluid dynamics; Evaporator; Mixture model; Volume fraction | ||
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