Abstract
The purpose of this study is to investigate the effect of spiral springs with the square cross-section area on heat transfer and pressure drop in heat exchangers. The springs were fitted inside a circular cross-section copper tube. The diameter and length of the copper tube were 25.4 mm and 1820 mm, respectively. The experiments were performed with 9 spiral springs of 12 and 15 mm diameter in four pitches of 2, 5,10,20 mm and 21 mm diameter in three pitches 10, 20 and 30. The fluid used in all experiments was water and the Reynolds number for the hot water flow into the copper tube was in the range of 22,462 to 36,456. Cold water was used to cool around the copper tube and rate of cold water flow was also 0.1547 kg / s. The heat transfer coefficient increased by 45% after the springs were placed inside the copper tube in comparison to the no-spring condition. However, the pressure drop in the worst case increased by 77%. It can also be seen that the heat transfer coefficient increased to 20% by increasing the diameter of the springs by 75%. Meanwhile, the springs with a diameter of 21 mm and 12 mm has the most and the least effect on increasing the heat transfer coefficient, respectively.
Similar content being viewed by others
Abbreviations
- Ai :
-
Area of the heat transfer surface (mm)
- Cp:
-
Specific heat of fluid [J /kg K]
- D:
-
Diameter of the copper tube (mm)
- Dh :
-
Hydraulic diameter (mm)
- Do :
-
Inner diameter of the outer tube (plastic tube) (mm)
- d:
-
Diameter of the spiral spring (mm)
- f:
-
Friction factor
- fp :
-
Friction factor of plain tube
- fs :
-
Friction factor for the tube with the spiral spring
- h:
-
Heat transfer coefficient [W/m2 .K]
- k:
-
Fluid thermal conductivity [W/m.K]
- L:
-
Test tube length (mm)
- \( \dot{\mathrm{m}} \) :
-
Mass flow rate [Kg/ s]
- Nu:
-
Nusselt number
- Nup :
-
Nusselt number for the plain tube
- Nus :
-
Nusselt number for the tube with the spiral spring
- ∆P:
-
Pressure drop of copper tube [pa]
- P:
-
Pitches of the spiral spring (mm)
- Pr:
-
Prandtl number
- Qave :
-
Average heat transfer rate (W)
- Q:
-
Heat transfer (W)
- Rec :
-
Reynolds number of cold water
- Re:
-
Reynolds number of hot water
- ∆Tlm :
-
Logarithmic temperature difference
- Tin.c :
-
Cold water temperature at the entrance of the copper tube [°C]
- Tout.c :
-
Cold water temperature at copper tube outlet [°C]
- Tin.h :
-
Hot water temperature at the entrance of the copper tube [°C]
- Tout.h :
-
Hot water temperature at copper tube outlet [°C]
- U:
-
Overall heat transfer coefficient [W/m2. K]
- η:
-
Thermal performance factor
- μ:
-
Fluid dynamic viscosity of hot water [kg /m s]
- μc :
-
Fluid dynamic viscosity of cold water [kg /m s]
- ρ:
-
Fluid density of hot water [kg/ m3]
- ave.:
-
Average
- c:
-
cold water
- h:
-
hot water
- i:
-
inner
- in:
-
inlet
- lm:
-
Logarithmic temperature
- o:
-
outer
- out:
-
outlet
- p:
-
plain tube
- s:
-
spiral spring
References
Alam T, Kim M-H (2018) A comprehensive review on single phase heat transfer enhancement techniques in heat exchanger applications. Renewable Sustainable Energy Rev 81(1):813–839. https://doi.org/10.1016/j.rser.2017.08.060
Kumar B (2018) Gaurav Prakash Srivastava, Manoj Kumar, Anil Kumar Patil, “a review of heat transfer and fluid flow mechanism in heat exchanger tube with inserts”. Chem Eng Process 123:126–137. https://doi.org/10.1016/j.cep.2017.11.007
Akhavan-Behabadi MA, Kumar R, Salimpour MR, Azimi R (2010) Pressure drop and heat transfer augmentation due to coiled wire inserts during laminar flow of oil inside a horizontal tube. Int J Therm Sci 49(2):373–379. https://doi.org/10.1016/j.ijthermalsci.2009.06.004
Saha SK (2010) Thermal and friction characteristics of laminar flow through rectangular and square ducts with transverse ribs and wire coil inserts. Exp Therm Fluid Sci 34(1):63–72. https://doi.org/10.1016/j.expthermflusci.2009.09.003
Eiamsa-ard S, Nivesrangsan P, Chokphoemphun S, Promvonge P (2010) Influence of combined non-uniform wire coil and twisted tape inserts on thermal performance characteristics. Int Commun Heat Mass Transfer 37(7):850–856. https://doi.org/10.1016/j.icheatmasstransfer.2010.05.012
Gunes S, Ozceyhan V, Buyukalaca O (2010) Heat transfer enhancement in a tube with equilateral triangle cross sectioned coiled wire inserts. Exp Therm Fluid Sci 34(6):684–691. https://doi.org/10.1016/j.expthermflusci.2009.12.010
Saeedinia M, Akhavan-Behabadi MA, Nasr M (2012) Experimental study on heat transfer and pressure drop of nanofluid flow in a horizontal coiled wire inserted tube under constant heat flux. Exp Therm Fluid Sci 36:158–168. https://doi.org/10.1016/j.expthermflusci.2011.09.009
San J-Y, Huang W-C, Chen C-A (2015) Experimental investigation on heat transfer and fluid friction correlations for circular tubes with coiled-wire inserts. Int Commun Heat Mass Transfer 65:8–14. https://doi.org/10.1016/j.icheatmasstransfer.2015.04.008
Chang SW, Gao JY, Shih HL (2015) Thermal performances of turbulent tubular flows enhanced by ribbed and grooved wire coils. Int J Heat Mass Transfer 90:1109–1124. https://doi.org/10.1016/j.ijheatmasstransfer.2015.07.070
Akhavan-Behabadi MA, Shahidi M, Aligoodarz MR (2015) An experimental study on heat transfer and pressure drop of MWCNT–water nano-fluid inside horizontal coiled wire inserted tube. Int Commun Heat Mass Transfer 63:62–72. https://doi.org/10.1016/j.icheatmasstransfer.2015.02.013
Mirzaei M, Azimi A (2016) Heat transfer and pressure drop characteristics of Graphene oxide/water Nanofluid in a circular tube fitted with wire coil insert. Exp Heat Transfer 26(2):173–187. https://doi.org/10.1080/08916152.2014.973975
Syam Sundar L, Bhramara P, Ravi Kumar NT, Singh MK, Sousa ACM (2017) Experimental heat transfer, friction factor and effectiveness analysis of Fe3O4 nanofluid flow in a horizontal plain tube with return bend and wire coil inserts. Int J Heat Mass Transfer 106:440–453. https://doi.org/10.1016/j.ijheatmasstransfer.2017.02.022
Sharafeldeen MA, Berbish NS, Moawed MA, Ali RK (2017) Experimental investigation of heat transfer and pressure drop of turbulent flow inside tube with inserted helical coils. Heat Mass Transfer 53(4):1265–1276. https://doi.org/10.1007/s00231-016-1897-z
Keklikcioglu O, Ozceyhan V (2018) Experimental investigation on heat transfer enhancement in a circular tube with equilateral triangle cross sectioned coiled-wire inserts. Appl Therm Eng 131:686–695. https://doi.org/10.1016/j.applthermaleng.2017.12.051
Salari S, Goudarzi K (2017) Intensification of heat transfer in heater tubes of city gas stations using spiral spring inserts. Therm Sci Eng Progress 3:123–132. https://doi.org/10.1016/j.tsep.2017.07.005
Hong Y, Juan D, Wang S, Huang S-M, Ye W-B (2018) Heat transfer and fluid flow behaviors in a tube with modified wire coils. Int J Heat Mass Transfer 124:1347–1360. https://doi.org/10.1016/j.ijheatmasstransfer.2018.04.017
Omara MA, Abdelatief MA (2018) Experimental study of heat transfer and friction factor inside elliptic tube fixed with helical coils. Appl Therm Eng 134:407–418. https://doi.org/10.1016/j.applthermaleng.2018.02.017
Jalil E, Goudarzi K (2018) Experimental study of heat transfer enhancement in the evaporator of single-effect absorption chiller using new different tube insert. Appl Therm Eng 128:1–9. https://doi.org/10.1016/j.applthermaleng.2017.09.004
Xin F, Liu Z, Wang S, Liu W (2018) Study of heat transfer in oscillatory flow for a Stirling engine heating tube inserted with spiral spring. Appl Therm Eng 143:182–192. https://doi.org/10.1016/j.applthermaleng.2018.07.071
Gnielinski V (1976) New equations for heat and mass transfer in turbulent pipe and channel flow. Int Chem Eng 16(2):359–368
Moffat RJ (1988) Describing uncertainties in experimental results. Exp Therm Fluid Sci 1(1):3–17. https://doi.org/10.1016/0894-1777(88)90043-X
Petukhov BS (1970) Heat transfer and friction in turbulent pipe flow with variable physical properties. Adv Heat Tran 6:503–564. https://doi.org/10.1016/S0065-2717(08)70153-9
Colburn AP (1933) Trans.AIChE 29:174–210
Webb RL (1981) Performance evaluation criteria for use of enhanced heat transfer surfaces in heat exchanger design. Int J Heat Mass Transfer 24(4):715–726. https://doi.org/10.1016/0017-9310(81)90015-6
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher’s note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Ghasemi Jolaghani, A., Mirabdolah Lavasani, A. Improvement of heat transfer in heat exchangers with spiral springs with the square cross-section area. Heat Mass Transfer 56, 2801–2812 (2020). https://doi.org/10.1007/s00231-020-02895-w
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00231-020-02895-w