• Vol 6, No 3 (2015)
  • Mechanical Engineering

Experimental and Simulation Study on the Performance of Counter Flow Closed Cooling Tower Systems

Budihardjo , Nasruddin , Mohammad Hafil Nugraha

Corresponding email: budihardjo@eng.ui.ac.id


Published at : 29 Jul 2015
IJtech : IJtech Vol 6, No 3 (2015)
DOI : https://doi.org/10.14716/ijtech.v6i3.986

Cite this article as:

Budihardjo, Nasruddin, Nugraha, M.H., 2015. Experimental and Simulation Study on the Performance of Counter Flow Closed Cooling Tower Systems. International Journal of Technology. Volume 6(3), pp. 365-379

283
Downloads
Budihardjo Department of Mechanical Engineering, Faculty of Engineering, Universitas Indonesia Kampus Baru UI Depok, Depok 16424, Indonesia
Nasruddin Department of Mechanical Engineering, Faculty of Engineering, Universitas Indonesia Kampus Baru UI Depok, Depok 16424, Indonesia
Mohammad Hafil Nugraha Department of Mechanical Engineering, Faculty of Engineering, Universitas Indonesia Kampus Baru UI Depok, Depok 16424, Indonesia
Email to Corresponding Author

Abstract
image

Cooling towers are required in building HVAC systems that use water as the cooling condenser fluid. Cooling towers used in this study are of the forced draft, counter flow, indirect/closed evaporative type. This study sought to demonstrate the performance characteristics of a closed system cooling tower by its effectiveness value, Number of Transfer Units (NTU), cooling capacity, and overall heat transfer and mass coefficient of the cooling tower. Experiments were performed on a heat exchanger coil intercrossed with ? inch diameter intersections on parallel lines. Results of the experiment were then compared with the heat and mass transfer correlations taken from previous studies, and also combined with Computational Fluid Dynamics (CFD) simulations to examine the physical processes that occur in the cooling towers. All the experimental results, theoretical calculations and CFD simulations used variations of warm water mass, cold air, and water spray to present a clear description of the performance characteristics of a closed system cooling tower. The results of this study have shown that an increase in the amount of water spray mass flow causes an increase in the effectiveness value, heat transfer and overall mass transfer, as well as the cooling capacity of the cooling tower. The waste heat typically utilizes up to 80% of latent evaporation heat, and 20% of sensible air heat; however, waste heat in the closed system cooling tower utilizes 100% of latent evaporation heat. The mass transfer coefficient rate tends to be stable for a small mass of water spray.

CFD, Cooling tower, Evaporative cooling, NTU, Spray water

References

Duan, Z., Zhan, C., Zhang, X., 2012. Indirect Evaporative Cooling: Past, Present and Future Potentials. Renewable and Sustainable Energi Reviews, Volume 16, pp. 6823–6850

Facão, J., Oliveira, A., 2004. Heat and Mass Transfer Correlations for the Design of Small Indirect Contact Cooling Towers. Applied Thermal Engineering, Volume 24, pp. 1969–1978

Gan, G., Riffat, S.B., Shao, L., Doherty, P., 2001. Application of CFD to Closed-wet Cooling Towers. Applied Thermal Engineering, Volume 21, pp. 79–92

Hasan, A., 2005. Performance Analysis of Heat Transfer Processes from Wet and Dry Surfaces: Cooling Towers and Heat Exchangers. Ph.D. Dissertation, Helsinki University of Technology

Hasan, A., Siren, K., 2002. Theoretical and Computational Analysis of Closed Wet Cooling Towers and its Applications in Cooling Buildings. Energy and Buildings, Volume 34, pp. 477-486

Heyns, J.A., Kröger, D.G., 2010. Experimental Investigation into the Thermal-flow Performance Characteristics of an Evaporative Cooler. Applied Thermal Engineering, Volume 30, pp. 492–498

Jiang, J-J., Liu, X-H., Jiang, Y., 2013. Experimental and Numerical Analysis of a Cross-flow Closed Wet Cooling Tower. Applied Thermal Engineering, Volume 61, pp. 678–689

Kaiser, A.S., Lucas, M., Viedma, A., Zamora, B., 2005. Numerical Model of Evaporative Cooling Processes in a New Type of Cooling Tower. International Journal of Heat and Mass Transfer, Volume 48, pp. 986–999

Khan, J.U.R., Yaqub, M., Zubair, S.M., 2003. Performance Characteristics of Counter Flow Wet Cooling Towers. Energy Convers Manage, Volume 44, pp. 2073–2091

Kloppers, J.C., Kröger, D.G., 2005. Cooling Tower Performance Evaluation: Merkel Poppe and e-NTU Methods of Analysis. ASME J Eng Gas Turbin Power, Volume 127, pp. 1–7

Merkel, F., 1925. Verdunstungskühlung. VDI-Zeitchrift, Volume 70, pp. 123–128

Mizushina, T., Ito, R., Miyashita, H., 1967. Experimental Study of an Evaporative Cooler. International Chemical Engineering, Volume 7(4), pp. 727–732

Mizushina, T., Ito, R., Miyashita, H., 1968. Characteristics and Methods of Thermal Design of Evaporative Cooler. International Chemical Engineering, Volume 8(3), pp. 532–538

Papaefthimiou, V.D., Rogdakis, E.D., Koronaki, I.P., Zannis, T.C., 2012. Thermodynamic Study of the Effects of Ambient Air Conditions on the Thermal Performance Characteristics of a Closed Wet Cooling Tower. Applied Thermal Engineering, Volume 33–34, pp. 199–207

Poppe, M., Rögener, H., 1991. Berechnung von Rückkühlwerken. VDI-Wärmeatlas, Mi1-Mi, p. 15

Riffat, S.B., Oliveira, A., Facão, J., Gan, G., Doherty, P., 2000. Thermal Performance of a Closed Wet Cooling Tower for Chilled Ceilings: Measurement and CFD Simulation. Int. J. Energy Res, Volume 24, pp. 1171-1179

Sarker, M.M.A., Kim, E., Moon, C.G., Yoon, J.I., 2008. Performance Characteristics of the Hybrid Closed Circuit Cooling Tower. Energy and Buildings, Volume 40, pp. 1529–1535

Shim, G.J., Baek, S.M., Moon, C.G., Lee, H.S., 2008. Performance Characteristics of a Closed Circuit Cooling Tower with Multi Path. Heat Transfer Engineering, Volume 31, pp. 992–997

Stabat, P., Marchio, D., 2003. Simplified Model for Indirect-contact Evaporative Cooling-tower Behaviour. Applied Energy, Volume 78, pp. 433–451

Xia, Z.Z., Chen, C.J., Wang, R.Z., 2011. Numerical Simulation of a Closed Wet Cooling Tower with Novel Design. International Journal of Heat and Mass Transfer, Volume 54, pp. 2367–2374

Zheng, W-Y., Zhu, D-S., Song, J., Zeng, L-D., Zhou, H-j., 2012. Experimental and Computational Analysis of Thermal Performa

Table of Contents