Experimental Investigation on the Effect a Rotational Shaft on the Thermal Behavior of a Circular Tube under Constant Heat Flux

Document Type : Original Article

Authors

Mechanical Engineering Department, Technical Education Faculty, Urmia University, Urmia, West Azerbaijan, Iran

Abstract

Active and passive methods are two main mechanisms of heat transfer improvement. The active methods use external forces to improve heat transfer. This investigation evaluates the thermal and frictional behavior of a circular tube containing a rotational shaft. Constant heat flux was exerted to the circular tube. The fluid inlet and outlet temperature as well as wall temperature of tubes were measured to calculate the hat transfer coefficient. The Re (Reynolds) number was between 800-2000. Also, the dimensionless rotational speed (Rs) had the values of 1,1.5, 2, 2.5 and 3. Results revealed that the rotational shaft could increase the Nu number. Up to %18. Also, the results showed that the rotational shaft could significantly increase the pressure drop and friction factor. The maximum increment of %78 was achieved for friction factor. It was revealed that the use of rotational shaft could be more efficient at low Re numbers and low dimensionless rotational speeds. Also, it was found that by the increment of Reynolds number and being in the transient regime the efficiency of the system would improve.

Keywords


1.     Kumar, B., Srivastava, G.P., Kumar, M. and Patil, A.K., "A review of heat transfer and fluid flow mechanism in heat exchanger tube with inserts", Chemical Engineering and Processing-Process Intensification,  Vol. 123, (2018), 126-137. https://doi.org/10.1016/j.cep.2017.11.007
2.     Kareem, Z.S., Jaafar, M.M., Lazim, T.M., Abdullah, S. and Abdulwahid, A.F., "Passive heat transfer enhancement review in corrugation", Experimental Thermal and Fluid Science,  Vol. 68, (2015), 22-38. https://doi.org/10.1016/j.expthermflusci.2015.04.012
3.     Gupta, N.K., Tiwari, A.K. and Ghosh, S.K., "Heat transfer mechanisms in heat pipes using nanofluids–a review", Experimental Thermal and Fluid Science,  Vol. 90, (2018), 84-100. https://doi.org/10.1016/j.matpr.2017.01.119
4.     Gugulothu, R., Somanchi, N.S., Reddy, K.V.K. and Akkiraju, K., "A review on enhancement of heat transfer in heat exchanger with different inserts", Materials Today: Proceedings,  Vol. 4, No. 2, (2017), 1045-1050. https://doi.org/10.1016/j.matpr.2017.01.118
5.     White, A., "Flow of a fluid in an axially rotating pipe", Journal of Mechanical Engineering Science,  Vol. 6, No. 1, (1964), 47-52. https://doi.org/10.1243/JMES_JOUR_1964_006_010_02
6.     Suppiah Singaram, S., Lodha, H. and Jachuck, R.J., "Experimental investigation of continuous single‐phase rimming flow in a horizontal rotating cylinder", AIChE Journal,  Vol. 60, No. 11, (2014), 3939-3950. DOI:10.1002/aic.14569
7.     Chatterjee, S., Sugilal, G. and Prabhu, S., "Flow transitions in a partially filled rotating inclined pipe with continuous flow", Experimental Thermal and Fluid Science,  Vol. 83, (2017), 47-56. https://doi.org/10.1016/j.expthermflusci.2016.12.007
8.     Krivosheev, B., Kukharskii, M. and Portnov, V., "Heat transfer in the evaporator section of a rotating heat pipe at low rotational speeds", Inzhenerno Fizicheskii Zhurnal,  Vol. 37, (1979), 27-34. https://doi.org/10.1016/j.ijheatmasstransfer.2007.07.020
9.     Chatterjee, S., Sugilal, G. and Prabhu, S., "Heat transfer in a partially filled rotating pipe with single phase flow", International Journal of Thermal Sciences,  Vol. 125, (2018), 132-141. DOI:10.1016/J.IJTHERMALSCI.2017.11.024
10.   Hussain, S.H. and Hussein, A.K., "Mixed convection heat transfer in a differentially heated square enclosure with a conductive
 
 
 
 
rotating circular cylinder at different vertical locations", International Communications in Heat and Mass Transfer,  Vol. 38, No. 2, (2011), 263-274. https://doi.org/10.1016/j.icheatmasstransfer.2010.12.006
11.   Park, Y.G., Yoon, H.S. and Ha, M.Y., "Natural convection in square enclosure with hot and cold cylinders at different vertical locations", International Journal of Heat and Mass Transfer,  Vol. 55, No. 25-26, (2012), 7911-7925. https://doi.org/10.1016/j.ijheatmasstransfer.2012.08.012
12.   Yoon, H.S., Park, Y.G. and Jung, J.H., "Natural convection in a square enclosure with differentially heated two horizontal cylinders", Numerical Heat Transfer, Part A: Applications,  Vol. 65, No. 4, (2014), 302-326. https://doi.org/10.1080/10407782.2013.831679
13.   Kareem, A.K. and Gao, S., "Mixed convection heat transfer of turbulent flow in a three-dimensional lid-driven cavity with a rotating cylinder", International Journal of Heat and Mass Transfer,  Vol. 112, (2017), 185-200. https://doi.org/10.1016/j.ijheatmasstransfer.2017.04.118
14.   Selimefendigil, F. and Öztop, H.F., "Numerical study and identification of cooling of heated blocks in pulsating channel flow with a rotating cylinder", International Journal of Thermal Sciences,  Vol. 79, (2014), 132-145. DOI:10.1016/j.ijthermalsci.2014.01.010
15.   Alawadhi, E.M., "Numerical simulation of fluid flow past an oscillating triangular cylinder in a channel", Journal of Fluids Engineering,  Vol. 135, No. 4, (2013). https://doi.org/10.1115/1.4023654
16.   Sutherland, B. and Linden, P., "Internal wave excitation by a vertically oscillating elliptical cylinder", Physics of Fluids,  Vol. 14, No. 2, (2002), 721-731. https://doi.org/10.1063/1.1430438
17.   Pourgholam, M., Izadpanah, E., Motamedi, R. and Habibi, S.E., "Convective heat transfer enhancement in a parallel plate channel by means of rotating or oscillating blade in the angular direction", Applied Thermal Engineering,  Vol. 78, (2015), 248-257. https://doi.org/10.1016/j.applthermaleng.2014.12.057
18.   Moffat, R.J., "Describing the uncertainties in experimental results", Experimental Thermal and Fluid Science,  Vol. 1, No. 1, (1988), 3-17.
19.   Rezaei, R.A., Jafarmadar, S. and Khorasani, S., "Presentation of frictional behavior of micro helical tubes with various geometries and related empirical correlation; an experimental study", International Journal of Thermal Sciences,  Vol. 140, (2019), 377-387. https://doi.org/10.1016/j.ijthermalsci.2019.03.011
20.   Khorasani, S., Jafarmadar, S., Pourhedayat, S., Abdollahi, M.A.A. and Heydarpour, A., "Experimental investigations on the effect of geometrical properties of helical wire turbulators on thermal performance of a helically coiled tube", Applied Thermal Engineering,  Vol. 147, (2019), 983-990. https://doi.org/10.1016/j.applthermaleng.2018.09.092
21.   Sun, M. and Zeng, M., "Investigation on turbulent flow and heat transfer characteristics and technical economy of corrugated tube", Applied Thermal Engineering,  Vol. 129, (2018), 1-11. https://doi.org/https://doi.org/10.1016/j.applthermaleng.2017.09.136
22.   Promvonge, P., "Thermal augmentation in circular tube with twisted tape and wire coil turbulators", Energy Conversion and Management,  Vol. 49, No. 11, (2008), 2949-2955. DOI: 10.1016/j.enconman.2008.06.022