Velocity and Pressure Analysis in a Divergent Area Fitted with Dimpled Hub


  • Ehan Sabah Shukri Askari
  • Wirachman Wisnoe
  • . .





annular diffuser, dimpled hub, velocity distribution, CFD.


A diffuser fitted with turbulators is able to enhance the distribution of both velocity and pressure. This research presents a numerical analysis for an annular diffuser type with dimpled hub. The diffuser is used to increase the static pressure by consuming kinetic energy. Three different hub models which are straight dimpled hub (SDH), divergent dimpled hub (DDH) and cone dimpled hub (CDH) are simulated to study their effects on the velocity and pressure profile for an annular diffuser. Results indicate that the insertion of the three dimpled hub models enhances velocity and pressure distribution through the diffuser. Numerical results recorded that the velocity disturbance enhanced up to 10%, 20% and 4% for the SDH, DDH, and CDH, respectively compared with the diffuser without dimples. Furthermore, the results show that the velocity distribution is the best with SDH model and the static pressure with CDH is the largest.




[1] H. A. Abdalla, M. M. El-Mayit, A. A. Abd El-Hamid, and A. M. El-Shazly, “Study of swirling turbulent flow and heat transfer characteristics in conical diffusers,†Proceedings of ICFDP 8: Eighth International Congress of Fluid Dynamics & Propulsion. Egypt ICFDP8-EG-114N, 2006.

[2] S. Bhattacharyya, T. Roy, N. Ghosh, Bandyopadhyay, and P. P. Sarkar, “Convective heat transfer enhancement in low Reynold number of a circular pipe with full length,†International Journal of Mechanical and Production Engineering, vol. 2, no. 9, pp. 6–10, 2014.

[3] P. S. Rao, and K. K. Kumar, “Numerical and experimental investigation of heat transfer augmentation in double pipe heat exchanger with helical and twisted tape inserts,†International Journal of Emerging Technology and Advanced Engineering., vol. 4, no. 9, pp. 180–192, 2014.

[4] R. Prakash, “Experimental investigations of flow through annular diffuser with and without struts,†European Journal of Scientific Research, vol. 52, no. 3, pp. 366–384, 2011.

[5] S. Selvam, P. Thiyagarajan, and S. Suresh, “Experimental studies on effect of bonding the twisted tape with pins to the inner surface of the circular tube,†Thermal Science, vol. 18, no. 4, pp. 1273–1283, 2014.

[6] A. R. Anvari, K. Javaherdeh, M. Emami-Meibodi, and A. M. Rashidi, “Numerical and experimental investigation of heat transfer behavior in a round tube with the special conical ring inserts,†Energy Conversion and Management, vol. 88, pp. 214–217, 2014.

[7] Zheng, P. Liu, F. Shan, Z. Liu, and W. Liu, “Numerical investigations of the thermal-hydraulic performance in a rib-grooved heat exchanger tube based on entropy generation analysis,†Applied Thermal Engineering, vol. 99, pp. 1071–1085, 2016.

[8] F. Sun, Y. Yao, X. Li, G. Li, and Z. Sun, “A numerical model for predicting distributions of pressure and temperature of superheated steam in multi-point injection horizontal wells,†International Journal of Heat and Mass Transfer, vol. 121, pp. 282-289, 2018.

[9] Jerson R.P. Vaz, and David H. Wood, “Effect of the diffuser efficiency on wind turbine performance,†Renewable Energy, vol. 126, pp. 969-977, 2018.

[10] A. Bosioc, C. Tanasa, S. Muntean, and R. F. Susan-Resiga, “Pressure recovery improvement in a conical diffuser with swirling flow using water jet injection,†The Publication House Proceeding of The Romanian Academy, Series A, vol. 11, pp. 245–252, 2010.

[11] Anupriya, and S. Jayanti, “Experimental and modeling studies of gas-liquid vertical annular flow through a diverging section,†International Journal of Multiphase Flow, vol. 67, pp. 180–190, 2014.

[12] L. Zheng, Y. Xie, and D. Zhang, “Numerical investigation on heat transfer performance and flow characteristics in circular tubes with dimpled twisted tapes using Al2O3-water nanofluid,†International Journal of Heat and Mass Transfer, vol. 111, pp. 962-981, 2017.

[13] N. Chimres, C. Wang, and S. Wongwises, “Optimal design of the semi-dimple vortex generator in the fin and tube heat exchanger,†International Journal of Heat and Mass Transfer, vol. 120, pp. 1173-1186, 2018.

[14] S. Wanga, W. Dua, L. Luo, D. Qiu, X. Zhang, and S. Li, “Flow structure and heat transfer characteristics of a dimpled wedge channel with a bleed hole in dimple at different orientations and locations,†International Journal of Heat and Mass Transfer, vol. 117, pp. 1216-1230, 2018.

[15] S. Xie, Z. Liang, L. Zhang, Y. Wang, H. Ding, and J. Zhang, “Numerical investigation on heat transfer performance and flow characteristics in enhanced tube with dimples and protrusions,†International Journal of Heat and Mass Transfer, vol. 122, pp. 602-613, 2018.

[16] P. Promvonge, S. Suwannapan, M. Pimsarn and C. Thianpong, “Experimental study on heat transfer in square duct with combined twisted-tape and winglet vortex generators,†International Communications in Heat and Mass Transfer, vol. 59, pp. 158–165, 2014.

[17] D. Erdemir, S. Gunes, V. Ozceyhan, and N. Altuntop, “Numerical investigation of heat transfer enhancement and pressure drop in heat exchanger tube fitted with dual twisted tape elementsâ€, Recent Researches in Mechanical Engineering, no. ISBN: 978–1–61804–153–1, pp. 167–172, 2013.

[18] D. Flórez-Orrego, W. Arias, D. López, and H. Velásquez, “Experimental and CFD study of a single phase cone-shaped helical coiled heat exchanger: an empirical correlationâ€, Proceedings of The 25th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, pp. 375–394, 2012.

View Full Article:

How to Cite

Sabah Shukri Askari, E., Wisnoe, W., & ., . (2018). Velocity and Pressure Analysis in a Divergent Area Fitted with Dimpled Hub. International Journal of Engineering & Technology, 7(4.25), 185–189.
Received 2018-11-30
Accepted 2018-11-30
Published 2018-11-30