HEAT TRANSFER ENHANCEMENT USING CIRCUMFERENTIAL FINNED TWISTED TAPE HEAT EXCHANGER

Authors

  • Sudha Brahma Naidu P. Department of Mechanical Engineering, College of Engineering (A) Andhra University, Visakhapatnam, Andhra Pradesh, India
  • P. S. Kishore Department of Mechanical Engineering, College of Engineering (A) Andhra University, Visakhapatnam, Andhra Pradesh, India

DOI:

https://doi.org/10.29121/granthaalayah.v5.i9.2017.2225

Keywords:

Augmentation, Reynolds Number, Nusselt Number, Shear Stress, Friction Factor, Thermal Performance Factor

Abstract [English]

The most desirable feature in any thermal equipment is the enhancement of heat transfer. Heat transfer is basically a slow process and is enhanced by adopting passive or active methods of enhancement. In passive enhancement methods, heat transfer is increased without demanding any external power source; while in active method, enhancement in heat transfer demand external power. In this work, a passive enhancement method is proposed and tested to check the extent of heat transfer enhancement noticed. A tube in shell heat exchanger is designed with circumferential fins attached along the length of tube and a spiral insert running inside the tube. One fluid is made to flow inside the tube under the influence of twisted tape and the shell side fluid is running around the tube continuously provoked by fins. Therefore, the hot and cold fluids were estimated to exchange more heat because of thorough mixing initiated in their flow paths. In this work, analysis was made in CFD package by creating a model that simulates experimentations observed in the literature. The results of experiments and results of CFD analysis were compared. Noticing the agreement between the results, the CFD model is given enhancements like circumferential fins and twisted tape to check the enhancement in heat transfer. The velocity and temperature contours were observed at various flow conditions (Reynolds numbers). Based on results of analysis, thermal performance factor is also estimated to check the increment in heat transfer with reference to hydraulic (or flow) parameters.

Downloads

Download data is not yet available.

References

Saha, S. K. and Dutta, A. (2001), Thermo-hydraulic study of laminar swirl flow through a circular tube fitted with twisted tapes. Trans. ASME, J. Heat Transfer, Vol.123, pp. 417–421. DOI: https://doi.org/10.1115/1.1370500

Saha, S. K. and Bhunia, K. (2000), Heat transfer and pressure drop characteristics of varying pitch twisted-tape-generated laminar smooth swirl flow. In Proceedings of 4th ISHMT– ASME Heat and Mass Transfer Conference, India, pp. 423–428.

Ray, S. and Date, A. W.(2003), Friction and heat transfer characteristics of flow through square duct with twisted tape insert, Int. J. Heat and Mass Transfer, Vol. 46, pp.889–902. DOI: https://doi.org/10.1016/S0017-9310(02)00355-1

Loknath, M. S. and Misal, R. D. (2002), An experimental study on the performance of plate heat exchanger and an augmented shell and tube heat exchanger for different types of fluids for marine applications. In Proceedings of 5th ISHMT– ASME Heat and Mass Transfer Conference, India, pp. 863–868

Sarma, P.K., Subramanyam, T., Kishore, P.S., Dharma Rao, V., Sadic Kakac., (2003) Laminar convective heat transfer with twisted tape inserts in a tube., International Journal of Thermal Sciences, Vol. 42, pp. 821-828. DOI: https://doi.org/10.1016/S1290-0729(03)00055-3

Saha, S. K. Dutta, A. and Dhal, S. K. (2001), Friction and heat transfer characteristics of laminar swirl flow through a circular tube fitted with regularly spaced twisted-tape elements. Int. J. Heat and Mass Transfer, Vol. 44, pp. 4211–4223. DOI: https://doi.org/10.1016/S0017-9310(01)00077-1

Al-Fahed, S. Chamra, L. M. Chakroun, W. (1999), Pressure drop and heat transfer comparison for both micro-fin tube and twisted-tape inserts in laminar flow. Exp. Thermal and Fluid Sci., Vol.18, pp.323–333.

Liao, Q. and Xin, M. D. (2000), Augmentation of convective heat transfer inside tubes with three-dimensional internal extended surfaces and twisted tape inserts. Chem. Eng. J.Vol.78, pp. 95–105. DOI: https://doi.org/10.1016/S1385-8947(00)00134-0

Sarma, P.K., Chada, K., Rao, V.D., Kishore, P.S., Subrahmanyam, T., Bergles, A.E., Evaluation of momentum and thermal eddy diffusivities for turbulent flow in tubes. International Journal of Heat and Mass Transfer 53 (5), 1237-1242 DOI: https://doi.org/10.1016/j.ijheatmasstransfer.2009.11.023

Al-Fahed, S. and Chakroun, W. (1996), Effect of tube tape clearance on heat transfer for fully developed turbulent flow in a horizontal isothermal tube. Int. J. Heat and Fluid Flow, Vol.17, pp. 173–178. DOI: https://doi.org/10.1016/0142-727X(95)00096-9

Wang, L. and Sunden, B. (2002), Performance comparison of some tube inserts. Int. Commun. Heat Transfer, Vol. 29, pp.45–56. DOI: https://doi.org/10.1016/S0735-1933(01)00323-2

Saha, S. K. and Chakraborty, D. (1997), Heat transfer and pressure drop characteristics of laminar flow through a circular tube fitted with regularly spaced twisted tape elements with multiple twists. In Proceedings of 3rd ISHMT–ASME Heat and Mass Transfer Conference, India, pp. 313–318.

BrahmaNaidu, P.S., (2017) Performance evaluation of circumferential finned twisted tape heat exchanger. M. Tech Thesis, Andhra University., Visakhapatnam.

Downloads

Published

2017-09-30

How to Cite

Naidu P., S. B., & Kishore, P. S. (2017). HEAT TRANSFER ENHANCEMENT USING CIRCUMFERENTIAL FINNED TWISTED TAPE HEAT EXCHANGER. International Journal of Research -GRANTHAALAYAH, 5(9), 152–163. https://doi.org/10.29121/granthaalayah.v5.i9.2017.2225