نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشکده مهندسی نفت، گاز و پتروشیمی، دانشگاه خلیج فارس
2 گروه مهندسی شیمی، دانشکده مهندسی نفت، گاز و پتروشیمی، دانشگاه خلیج فارس، بوشهر
چکیده
در این تحقیق، تأثیر تغییرات سرعت چرخش پروانه راشتون درون بیورآکتور به منظور پخش مناسب هوا، بررسی نرخ کرنش برشی، شبیه‌سازی و بررسی شد. شبیه‌سازی انجام شده با رویکرد چند فازی، مدل فاز پراکنده صفر معادله، با کمک مدل اغتشاش K-Epsilon Standard، به صورت پایا و سه‌بُعدی توسط مجموعه نرم‌افزاری ANSYS Products ورژن R3 2019 و نرم افزار Ansys CFX انجام گرفت. معادلات حاکم بر سیستم با روش حجم محدود برای کل سیستم محاسبه شد. به منظور تزریق مناسب هوا به درون بیورآکتور، از یک حلقۀ حباب‌ساز که در زیر پروانه قرار گرفته است، استفاده شد. نتایج به دست آمده نشان داد که افزایش سرعت چرخش پروانه می‌تواند به پخش بهتر هوا درون بیورآکتور کمک کند؛ اما از طرفی موجب افزایش نرخ کرنش برشی درون بیورآکتور می‌شود. همچنین، افزایش سرعت چرخش پروانه بیش از ۱۵۰ دور بر دقیقه موجب افزایش اغتشاش در مایع شده و تأثیرات آن روی فاز گاز کاهش می‌یابد. علاوه بر این، با در نظر گرفتن سرعت چرخش پروانه و تأثیر آن بر روی میزان اختلاط فاز گاز و مایع، تنش درون مایع و نرخ متوسط انتقال جرم، می‌توان سرعت ۳۵۰ تا ۴۵۰ دور بر دقیقه را برای سرعت بهینه در نظر گرفت. در نهایت، مشخص شد که با افزایش سرعت چرخش پروانه نمی‌توان به اختلاط بهتر در بیورآکتور رسید و می‌بایست سرعت بهینه را مشخص کرد.
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
Hydrodynamic simulation of stirred gas-liquid bioreactor for the optimization of the rotation speed of Rushton impellers using CFD
نویسندگان [English]
- Pedram Nasehi 1
- A. Azari 2
1 Faculty of Petroleum,, Gas and Petrochemical Engineering, Persian Gulf University
2 Faculty of Petroleum, Gas and Petrochemical Engineering, Persian Gulf University
چکیده [English]
In the present research, the effect of altering the rotational speed of the Rushton impeller inside the bioreactor was simulated and investigated for proper air distribution and changes in the shear stress rate. The simulation was performed using the multiphase approach of the zero-equation scattered phase model, via the K-Epsilon Standard perturbation model, in stable three-dimensional manner using ANSYS Products 2019 R3 and Ansys CFX software packages. The governing equations of the system were solved by the finite volume method for the entire system. To properly inject air into the bioreactor, a sparger ring was used under the impeller. The results revealed that increasing the impeller rotation speed could help better disperse the air inside the bioreactor. However, it also increases the shear stress rate inside the bioreactor. It was also shown that increasing the speed and getting more energy from it creates turbulence in the liquid. Additionally, its effect on the gas phase is reduced for the rotation speeds more than 150 rpm. Considering the rotation speed of the impeller and its effect on the mixing of gas-liquid phase, the intra-liquid stress and the average mass transfer rate, the speed of 350 to 450 rpm may be considered as the optimal speed. Finally, it was found that by increasing the rotation speed of the impeller, better mixing in the bioreactor could not be achieved and the optimal speed had to be determined.
کلیدواژه‌ها [English]
- Computational Fluid Dynamics
- Bioreactor
- Rushton impeller
- Gas-Liquid Bioreactor
- K-Epsilon model
- Garcia-Ochoa, F. and Gomez, E., “Theoretical Prediction of Gas–Liquid Mass Transfer Coefficient, Specific Area and Hold-up in Sparged Stirred Tanks”, Eng. Sci., Vol. 59, No. 12, pp. 2489–2501, 2004.
- Mendez, A. S. L., De Carli, G., and Garcia, C. V., “Evaluation of Powder Mixing Operation During Batch Production: Application to Operational Qualification Procedure in the Pharmaceutical Industry”, Powder Technol., Vol. 198, No. 2, pp. 310–313, 2010.
- Campolo, M., Sbrizzai, F., and Soldati, A., “Time-Dependent Flow Structures and Lagrangian Mixing in Rushton-Impeller Baffled-Tank Reactor”, Eng. Sci., Vol. 58, No. 8, pp. 1615–1629, 2003.
- Laakkonen, M., Moilanen, P., Alopaeus, V., and Aittamaa, J., “Modelling Local Bubble Size Distributions in Agitated Vessels”, Eng. Sci., Vol. 62, No. 3, pp. 721–740, 2007.
- Niño, L., Gelves, R., H. Ali, Solsvik, J., and Jakobsen, H., “Applicability of A Modified Breakage and Coalescence Model Based on The Complete Turbulence Spectrum Concept for CFD Simulation of Gas-Liquid Mass Transfer in a Stirred Tank Reactor”, Eng. Sci., Vol. 211, pp. 115272, 2020.
- Kuschel, M., and Takors, R., “Simulated Oxygen and Glucose Gradients as A Prerequisite for Predicting Industrial Scale Performance A Priori”, Bioeng., Vol. 117, No. 9, pp. 2760–2770, 2020.
- Gogate, P. R. and Pandit, A. B., “Survey of Measurement Techniques for Gas–Liquid Mass Transfer Coefficient in Bioreactors”, Eng. J., Vol. 4, No. 1, pp. 7–15, 1999.
- Doukhan, P., “Mixing: Properties and Examples”, Vol. 85. Springer Science & Business Media, 2012.
- Salehi, S., Heydarinasab, A., Shariati, F. P., Nakhjiri, A. T., and Abdollahi, K., “Parametric Numerical Study and Optimization of Mass Transfer and Bubble Size Distribution in a Gas-Liquid Stirred Tank Bioreactor Equipped with Rushton Turbine Using Computational Fluid Dynamics”, J. Chem. React. Eng., 2021.
- Qiu, N., Wang, P., Si, Q., Pettang, W. E. K., and Yuan, S., “Scale Process Effect on The Power Consumption Characteristics of A Novel Curved Rushton Turbine Within A Reactor Vessel”, Eng. Res. Des., Vol. 166, pp. 109–120, 2021.
- Agarwal, A., Singh, G., and Prakash, A., “Numerical Investigation of Flow Behavior in Double-Rushton Turbine Stirred Tank Bioreactor”, Today Proc., Vol. 43, pp. 51–57, 2021.
- Botlagunta, M., Rewaria, V., and P. Mathi, “Oxygen Mass Transfer Coefficient and Power Consumption in A Conventional Stirred-Tank Bioreactor Using Different Impeller in A Non-Newtonian Fluid: An Experimental Approach”, J. Chem. Chem. Eng., 2020.
- Nasehi, P., Moghaddam, M. S., Kandomal, M., Layghizadeh, A., and Moghaddam, A. M., “Process Simulation of Dodecyl Benzene Production Along with Energy Optimization in The Distillation Tower”.
- Gimbun, J., Rielly, C. D., and Nagy, Z. K., “Modelling of Mass Transfer in Gas–Liquid Stirred Tanks Agitated by Rushton Turbine and CD-6 Impeller: A Scale-up Study”, Eng. Res. Des., Vol. 87, No. 4, pp. 437–451, 2009.
- Shen, R., Jiao, Z., Parker, T., Sun, Y., and Wang, Q., “Recent Application of Computational Fluid Dynamics (CFD) in Process Safety and Loss Prevention: A Review”, Loss Prev. Process Ind., pp. 104252, 2020.
- Golshan, S., Sotudeh-Gharebagh, R., Zarghami, R., Mostoufi, N., Blais, B., and Kuipers, J. A. M., “Review and Implementation of CFD-DEM Applied to Chemical Process Systems”, Eng. Sci., Vol. 221, pp. 115646, 2020.
- Wilcox, D. C., “Turbulence Modeling for CFD”, Vol. 2. DCW Industries La Canada, CA, 1998.
- Armenante, P. M. and Chang, G.-M., “Power Consumption in Agitated Vessels Provided with Multiple-Disk Turbines”, Eng. Chem. Res., Vol. 37, No. 1, pp. 284–291, 1998.
- Kaiser, S. C., Werner, S., Jossen, V., Kraume, M., and Eibl, D., “Development of A Method for Reliable Power Input Measurements in Conventional and Single‐Use Stirred Bioreactors at Laboratory Scale”, Life Sci., Vol. 17, No. 5, pp. 500–511, 2017.
- Charoenpong, H., Osathanon, T., Pavasant, P., Limjeerajarus, N., Keawprachum, B., Limjeerajarus, C. N., Cheewinthamrongrod, V., Palaga, V., Lertchirakarn, V., Ritprajak, P., “Mechanical Stress Induced S100A7 Expression in Human Dental Pulp Cells to Augment Osteoclast Differentiation”, Oral Dis., Vol. 25, No. 3, pp. 812–821, 2019.
- Pascal, B., “Mathematician, Physicist and Thinker About God”, New York, NY: St. Martin, 1995.
- Guicciardini, N., “Isaac Newton, Philosophiae Naturalis Principia Mathematica, (1687)”, in Landmark Writings in Western Mathematics 1640-1940, Elsevier, 2005, pp. 59–87.
- Keawprachum, B., Limjeerajarus, N., Limjeerajarus, C. N., and Srisungsitthisunti, P., “Improved Design of A Cone-Shaped Rotating Disk for Shear Force Loading in a Cell Culture Plate”, In IOP Conference Series: Materials Science and Engineering, 2018, Vol. 297, No. 1, pp. 12025.
- ANSYS® Fluent, Release 16.2 ANSYS Workbench Help (ANSYS, Inc., USA).
- Amer, M., Feng, Y., and Ramsey, J. D., “Using CFD Simulations and Statistical Analysis to Correlate Oxygen Mass Transfer Coefficient to Both Geometrical Parameters and Operating Conditions in a Stirred‐Tank Bioreactor”, Prog., Vol. 35, No. 3, pp. e2785, 2019.
- Ochieng, A., Onyango, M. S., Kumar, A., Kiriamiti, K., and Musonge, P., “ Mixing in a Tank Stirred by a Rushton Turbine at a Low Clearance”, Chemical Engineering and Processing: Process Intensification, 47, No. 5 (2008): 842-851.
- Kremer, D. M., and Hancock, B. C., “Process Simulation in the Pharmaceutical Industry: A Review of Some Basic Physical Models”, Journal of Pharmaceutical sciences, 95, No. 3 (2006): 517-529.
- Ochieng, A., and Onyango, M. S., “Homogenization Energy in A Stirred Tank”, Chemical Engineering and Processing: Process Intensification, Vol. 47, pp. 1853-1860, 2008..
- Kopal, Z., “Tables of Supersonic Flow Around Cones”, Depart of Electrical Engineering, Center of Analysis, Massachusetts Institute of Technology, Cambridge, 1947.
- Fay, J. A. and Riddell, F. R., “Theory of Stagnation Point Heat Transfer in Dissociated Air”, Journal of the Aeronautical Sciences, Vol. 25, No. 2, Feb. 1958, pp. 73–85.
- Blottner, F.G., “Chemical Non Equilibrium Boundary Layer”, AIAA Journal, Vol. 2, No. 2, Feb. 1964, pp. 232–239.
- Blottner, F.G., “Non Equilibrium Laminar Boundary-Layer Flow of Ionized Air”, AIAA Journal, Vol. 2, No. 11, Nov. 1964, pp. 1921–1927.
- Hall, H.G., Eschenroeder, A.Q., and Marrone, P.V., “Blunt-Nose Inviscid Airflows with Coupled Non Equilibrium Processes”, Journal of the Aerospace Sciences, Vol. 29, No. 9, Sept. 1962, pp. 1038–1051.
- Chapman, D.R., “Computational Aerodynamics Development and Outlook”, AIAA Journal, Vol. 17, No. 12, Dec. 1979, pp. 1293–1313.
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