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Computational Fluid Dynamic Simulation of Flow Pattern and Heat Transfer in a Pilot Plant Spray Dryer with Cooling Air Jacket | ||
| تحقیقات مهندسی سازه های آبیاری و زهکشی | ||
| Article 7, Volume 14, Issue 1, January 0, Pages 89-106 PDF (626.49 K) | ||
| Document Type: Original Article | ||
| DOI: 10.22092/aridse.2013.102070 | ||
| Abstract | ||
| In this study, a numerical simulation was developed for flow in a pilot plant spray dryer with a cooling air jacket using the CFD method. A k-ɛ standard model was used to simulate turbulence. Air flow patterns and temperature variation in the chamber and cooling air jacket were estimated and suitable insulation calculated for the ceiling of the chamber. To verify the numerical results, velocity in the dryer was measured using a portable hot wire anemometer. Temperature variation was measured using transmitters installed at varying heights in the chamber. The numerical results showed that flow pattern consisted of a high velocity core extending toward the end of dryer. A circular flow around the circumference of the flow created vortices and caused particles to turn back toward the top of the dryer. The maximum temperature was at the core of the air flow and temperature decreased from the core toward the dryer wall. The flow path line in the cooling air jacket showed that the air layers were in smooth and harmonic motion around one another that produced little variation in axial velocity in this zone; however, at the junction of the cylindrical and conical parts of dryer jacket, some flow deviation occurred toward the wall. Adequate insulation for the ceiling was chosen according to the ratio of heat conductivity to the thickness of the insulator (K/L). | ||
| Keywords | ||
| Air Flow Pattern; Computational Fluid Dynamic; Cooling Air Jacket; Insulation; Pilot Plant Spray Dryer; Temperature Variation | ||
| References | ||
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