噴霧乾燥製程之熱流模擬

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姓名

兒德娜(Tsedendolgor Bat-Erdene) 查詢紙本館藏

畢業系所

機械工程學系

論文名稱

噴霧乾燥製程之熱流模擬
(THERMAL FLOW SIMULATION OF A SPRAY DRYING CHAMBER)

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摘要(中)

摘要

工業製程特別是食物加工業，普遍採用噴霧乾燥方式來保存牛奶以及蔬菜水果。噴霧乾燥以壓力噴嘴將待乾燥物噴入乾燥機，以高溫順流(co-current)空氣將待乾燥物水分蒸發而達到乾燥效果。預測空氣流速、溫度以及濕度分布對於設計噴霧乾燥機有重大的助益。本文採用計算流體力學(Computational Fluid Dynamics, CFD)商用軟體Fluent 14.5為噴霧乾燥製程建立熱流模擬模型。模型將空氣流視為連續體(Continuum) 以歐拉法 (Eulerian approach) 模擬其熱流行為，液滴群則視為離散的顆粒以拉格朗日法 (Lagrangian approach) 來模擬個別顆粒的移動軌跡與水分蒸發行為，二種方法耦合一併求解。我們先建立二維模型測試上述二相流模型的可行性，再延伸至實際的三維計算，並嘗試以水滴蒸發來近似牛奶的乾燥模式。奶粉製程要求乾燥機出口的空氣相對濕度需介於4-6%，而入口空氣溫度上限則為200℃，本文以此標準設定模擬條件，探討入口空氣溫度與液滴流量對於出口濕度的影響。三維模擬結果顯示本文模型可有效模擬空氣流速、濕度及溫度，亦可模擬液滴的飛行軌跡與顆粒尺寸因蒸發產生的變化與粒徑分布，結果將可以提供奶粉噴霧乾燥製程作為參考。

摘要(英)

ABSTRACT

Spray drying is one of the significant processes of various manufacturing sectors, especially for food processing industries which commonly use the process for drying milk, fruit juice, and vegetable juice. Prediction of the air flow, temperature, and humidity patterns in the co-current spray drying chamber with a pressure nozzle fitted at top of the drying chamber can help the design of the spray drying process.
This thesis presents thermal fluid simulations of a spray drying chamber. The demonstrations were performed with two-dimensional and three-dimensional models using a Computational Fluid Dynamics package (CFD) ‘Fluent 14.5’. The gas phase was exhibited as a continuum using the Euler approach and the droplet phase was exhibited by the Lagrange approaches. We investigated the drying process considering the effects of air flow interacted with atomizing water droplets. The two-dimensional simulation generally predicted the fast downward flowing core and slow recirculation zones around it which successfully verify the simulation model. After that we performed the three-dimensional simulations, considering the application to the milk drying process.
Most of the previous investigations have shown that the moisture content of the milk-air mixture is better to be around 4-6% (entering hot air up to 200℃) when the milk powders leave the chamber. This criterion was adopted to test our simulation parameters. The three-dimensional simulations correctly predicted the patterns of air flow, humidity, and temperature as well as particle tracks and distributions. The CFD simulation predicted the relationships between the inlet and outlet properties of the drying chamber. Variations of the inlet air temperature and water flow rate affect the outlet humidity of the exhaust air as well as the droplet sizes.

關鍵字(中)

★ 含水量
★ 牛奶乾燥
★ 熱流模擬
★ 噴霧乾燥
★ 相對溼度
★ 計算流體力學

關鍵字(英)

★ moisture content
★ milk drying
★ airflow simulation
★ spray drying process
★ relative humidity
★ CFD

論文目次

TABLE OF CONTENTS

ABSTRACT V
ACKNOWLEDGMENTS V I
LIST OF TABLES XII
LIST OF FIGURES XI
NOMENCLATURE XII

CHAPTERS
1 INTRODUCTION
1.1 1Statement of problem 1
1.2 Spray drying methods involved in the food engineering 3
1.3 Spray drying processes 4
1.3.1 The spray drying operations 8
1.3.2 Main types of flow directions in the drying chamber 9
1.3.3 Airflow simulation 10
1.3.4 Atomization process 11

2 CFD SIMULATION
2.1 Geometry of the spray dryer 13
2.2 Modeling approach 14
2.3 Mesh generation 20

3 RESULTS AND DISCUSSIONS
3.1 Mesh independent test 22
3.2 Thermal fluid behaviors of two-dimensional simulation 23
3.3 Thermal fluid behaviors of three-dimensional simulation 25
3.4 Suitable drying conditions 30
3.5 Particle size distribution 37
3.6 Influences of inlet air temperature and water flow rate 38

4 CONCLUSION 41

BIBLIOGRAPHY 43

參考文獻

BIBLIOGRAPHY
Anandharamakrishnan, C., Gimbun, J., Stapley, A.G.F., & Rielly, C.D., ‘A Study of Particle Histories During Spray Drying Using Computational Fluid Dynamic Simulations,’ Department of Chemical Engineering, Loughborough University Loughborough, Leicestershire, LE11 3TU, UK, 2010.
Ellen, M., Anthony, B., & Mcmahon, D., ‘Milk and dairy products in human nutrition,’ Food and Agriculture Organization of the United Nations, Rome, 2013.
Giuliano, T., Ferreira, J.M.F., & Fonseca, A.T., ‘Influence of particle size and particle size distribution on drying-shrinkage behavior of alumina slip cast bodies,’ Volume 25, Issue 6, pp 577-580, August 1999.
Hemi, A.A., & Saleh, S.N., ‘Computer Aided Design for Spray Dryers,’ Iraqi J.of Chem. And Petro. Eng., pp 27-34, 2007.
Huang, L., & Mujumdar, A.S., ‘A Parametric Study of the Gas-Flow Patterns and Drying Performance of Co- Current Spray,’ Dryer, Drying Technology, 21, 6, pp 957-978, 2003.
Huang, L., Kumar, K., & Mujumdar, A.S., ‘A Parametric Study of the Gas-Flow Patterns and Drying Performance of Current Spray Dryer,’ Drying Technology, 21, 6, pp 957-978, 2003.
John, R., Abrahamson, G.J., & Winchester, J.A., ‘Airflow patterns in an industrial milk powder spray dryer,’ Fifth International Conference on CFD in the Process Industries, CSIRO, Melbourne, Australia, 15 December 2006.
Kerkhof, P.J.A.M., & Schoeber, W.J.A.H., ‘Theoretical modeling of the drying behavior of droplet in spray dryers,’ Advances in pre-concentrating and dehydration of foods, ed. A. Spicer, Applied science publisher, London, pp 349-397, 1974.
Kieviet, F.G., ‘Modelling Quality in Spray Drying - Ph.D. dissertation,’ Endinhoven University of Technology, Netherland, 1997.
Kota, K., & Langrish, T., ‘Prediction of Deposition Patterns in a Pilot-Scale Spray Dryer Using CFD Simulations,’ Chem. Prod. And Proc. Modeling, 2(3), 26, and 2007.
Kulkarni, S.S., Chapman, C., & Shah, H., ‘Computational Fluid Dynamics (CFD) Mesh Independency Study of A Straight Blade Horizontal Axis Tidal Turbine,’ 2011.
Kuriakose., & Anandharamakrishnan, C., ‘Computational Fluid Dynamics Applications in Spray Drying of Food Products,’ 2010.
Langrish, T.A.G., & Fletcher, D.F., ‘Prospects for the Modelling and Design of Spray Dryers in the 21st Century,’ Drying Technology, 21 (2), pp 197–215, 2003.
Meng-Wai, W., Wanramliwan, D., Mujumdar, A.S., Zhonghua, W., Meor, T., & Sitimasrinda, T., ‘Non-Swirling Steady and Transient Flow Simulations in Short-Form Spray Dryers,’ Chemical Product and Process Modeling: Vol. 4: Iss.1, Article 20. DOI: 10.2202/1934-2659.1351, 2009.
Mezhericher, M., Levy, A., & Borde, I., ‘Modeling of Droplet Drying in Spray Chambers Using 2D and 3D Computational Fluid Dynamics,’ Pearlstone Centre for Aeronautical Engineering Studies, Department of Mechanical Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel, March 2009.

‘Official data of Mongolian Ministry of Food and Agriculture (MMFA),’ 2016.
Pearce, K.N., ‘Milk Powder, Food Science Section,’ New Zealand Dairy Research Institute, 2015.
Reay, D., ‘Modelling continuous convection dryers for particulate solid progress and problems,’ Drying 85, 5, pp.67-74, 1985.
Ricardo, A., Skurtys, O., & Fernando, O., ‘Atomizing Spray Systems for Application of Edible Coatings,’ April 2012.
Saleh, S.N., ‘Prediction of Air Flow, ‘Temperature and Humidity Patterns in a Pilot Plant Spray Dryer,’ Nahrain University, College of Engineering Journal (NUCEJ) Vol.13 No.1, pp 55-65, 2010.
Saleh, S.N., ‘CFD Simulations of a Co-Current Spray Dryer,’ World Academy of Science, Engineering and Technology, International Journal of Chemical, Molecular, Nuclear, Materials and Metallurgical Engineering Vol: 4, No:2, 2010.
Schuck, P., Dolivet, A., Mejean, S., & Jeantet, R., ‘Relative humidity of outlet air: the key parameter to optimize moisture content and water activity of dairy powders,’ Dairy Science & Technology, EDP Springer, pp.45-52, 2008.
Southwell, D.B., & Langrish, T.A.G., ‘Observations of flow patterns in a spray dryer,’ Drying Technology, 18 (3), pp 661–685, 2000.
Supplee, G.C., & Bellis, B., ‘The Solubility of Milk Powder as Affected by Moisture Content,’ Research Laboratory of The Dry Milk Company, Adams, New York, 2005.
Terence, A., ‘Powder sampling and particle size determination,’ (1st ed.). Amsterdam: Elsevier, 22 August 2011.
Westergaard, V., ‘Milk Powder Technology,’ GEA Nero, Copenhagen, February, 2010.
Zenichi, S., ‘Particle Structure in Spray-Dried Whole Milk and in Instant Skim Milk Powder as Related to Lactose Crystallization,’ Food Structure: Vol. 4: No. 2, Article 16. 1985.

指導教授

鍾志昂(Chung, Chih-Ang)

審核日期

2017-7-27

推文