Transient Cooling Of A Cylinder In Cross Flow Bounded By An Adiabatic Wall

Nafaw H. Saeid; Bashir S.  Abusahmin

Nafaw H. Saeid Mechanical Engineering Programme, Universiti Teknologi Brunei, Tungku Link, Gadong, BE 1410, Brunei Darussalam
Bashir S. Abusahmin Mechanical Engineering Programme, Universiti Teknologi Brunei, Tungku Link, Gadong, BE 1410, Brunei Darussalam

Keywords: Computational fluid dynamics, Transient analysis, Conjugate heat transfer, Circular cylindrical, Cross flow, Thermal inertia

Abstract

The present study investigates the parameters controlling the cooling process of a cylindrical food in the storage area for a period of time. Transient analysis of the conduction and convection (conjugate) heat transfer from a cylindrical food, or a cylindrical can filled with food is selected for numerical simulations. The cylinder is bounded by an adiabatic wall and the cold air is flowing normal to the cylinder axis (cross flow). The parameters investigated are: Reynolds number, food thermal properties (density, specific heat and thermal conductivity) and the cooling period. The range of the Reynolds number is selected from 50 to 500 to be in laminar flow conditions. Three different materials were selected according their thermal properties. The results are presented to show the cooling process starting from blowing cold air stream on the cylinder for a period of 4 hours. The results show that the food with low thermal inertia is cooled faster than that of high thermal inertia. The present results show also that the cooling process can be shortened by increasing the air velocity and lower its temperature.

References

1. Ambawa, A., Delele, M.A., Defraeye, T., Ho, Q.T., Opara, L.U., Nicolai, B.M., & Verboven, P. (2013). The use of CFD to characterize and design post-harvest storage facilities: Past, present and future, Computers and Electronics in Agriculture, 93, 184–194.
2. ANSYS FLUENT User's Guide (2011). ANSYSInc.,Southpointe 275, Technology Drive Canonsburg,PA15317,U.S.A.
3. Coutanceau, M., & Defaye, J. (1991). Circular cylinder wake configurations: a flow visualization survey, Applied Mechanics Reviews, 44, 255–305.
4. Dehghannya, J., Ngadi, M., & Vigneault, C. (2010). Mathematical Modeling Procedures for Airflow, Heat and Mass Transfer During Forced Convection Cooling of Produce: A Review, Food Engineering Reviews, 2, 227–243.
5. Fasina, O.O., & Fleming, H.P. (2001). Heat Transfer Characteristics of Cucumber during Blanching, Journal of Food Engineering, 47, 203-210.
6. Haider, M.J., Danish, S.N., Khan, W.A., Mehdi, S. U., & Abbasi, B.A. (2010). Heat Transfer and Fluid Flow over Circular Cylinders in Cross Flow, NUST Journal of Engineering Sciences, 3.
7. Khan, W. A., Culham J., & Yovanovich, M. (2005). Fluid flow around and heat transfer from an infinite circular cylinder, Journal of Heat Transfer, 27, 785-790.
8. Lemus-Mondaca, R.A., Vega-Galvez, A., & Moraga, N.O. (2011). Computational Simulation and Developments Applied to Food Thermal Processing, Food Engineering Reviews, 3, 121–135.
9. Marcotte, M., & Taherian, A. R. (2005). Thermophysical Properties of Processed Meat and Poultry Products, AIChE Annual Meeting Conference Proceedings, Food Engineering, Physical Properties of Food session.
10. Morgan, V. (1975). The overall convective heat transfer from smooth circular cylinders, Advances in Heat Transfer, Vol.11, Academic Press, New York, 199–264.
11. Norberg, C. (2003). Fluctuating lift on a circular cylinder: review and new measurements, J. Fluids Structures, 17: 57 – 96.
12. Norton, T., Sun, D.W. Grant, J. Fallon, R., & Dodd, V. (2007). Applications of computational fluid dynamics (CFD) in the modelling and design of ventilation systems in the agricultural industry: A review, Bioresource Technology, 98, 2386–2414.
13. Patankar, S.V. (1980). Numerical Heat Transfer and Fluid Flow, McGraw-Hill, New York, U.S.A.
14. Suleiman, B.M., Larfeldt, J., Leckner, B., & Gustavsson, M. (1999). Thermal conductivity and diffusivity of wood, Wood Science and Technology, 33, 465- 473.
15. Sumer, B.M., & Fredsoe, J. (1997). Hydrodynamics around Cylindrical Structures, World Scientific, London, UK.
16. Sumnern, D. (2010). Two circular cylinders in cross-flow: A review, Journal of Fluids and Structures, 26, 849–899.
17. Wang, J., Bras, R.L., Sivandran, G., & Knox, R.G. (2010), A simple method for the estimation of thermal inertia, Geophysical Research Letters, 37.
18. Wang, L., & Sun, D. (2003). Recent developments in numerical modelling of heating and cooling processes in the food industry - a review, Trends in Food Science & Technology, Volume 14, 408– 423.
19. Williamson, C.H.K., (1996). Vortex dynamics in the cylinder wake, Annual Review of Fluid Mechanics, 28, 477–539.
20. Zdravkovich, M. M. (1997). Flow around Circular Cylinders: Fundamentals, vol. 1, Oxford University Press, New York, U.S.A.
21. Zdravkovich, M. M. (2003). Flow Around Circular Cylinders: Fundamentals, vol. 2, Oxford University Press, New York, U.S.A.
22. Zukauskas, A. (1972). Advances in heat transfer, 93-160, Academic Press New York, U.S.A.