Heat Transfer and Pressure Drop in a Circular Tube Fitted with Twisted Tape Insert Having Continuous Cut Edges

Sarviya, R. M.; Fuskele, Veeresh

doi:10.1016/j.est.2018.07.001

Cited by 51 publications

(11 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…. This figure shows that applying twisted tape enhances the friction coefficient ratio due to the added surface area and flow blockage [52]. Furthermore, higher values for the friction coefficient ratio are observed in lower pitch values due to the creation of the more intense secondary flow shown in Figure 5; however, when the twisted tape pitch is equal to L, its enhancement is insignificant due to the creation of very weak secondary flow in the tube.…”

Section: Effect Of Twisted Tape Pitchmentioning

confidence: 83%

“…It is visible that as the flow enters the twisted tape at the tube inlet, the thermal boundary layer is disturbed and, due to the creation of secondary flow, the local increases; however, as the flow passes the twisted tape, the thermal boundary layer starts to develop normally, and as a result, it tends to develop towards the local Figure 11 shows the variations of the friction coefficient ratio with respect to PT for different pitch values and Re. This figure shows that applying twisted tape enhances the friction coefficient ratio due to the added surface area and flow blockage [52]. Furthermore, higher values for the friction coefficient ratio are observed in lower pitch values due to the creation of the more intense secondary flow shown in Figure 5; however, when the twisted tape pitch is equal to L, its enhancement is insignificant due to the creation of very weak secondary flow in the tube.…”

Section: Effect Of Truncated Twisted Tape Position and Percentagementioning

confidence: 83%

See 1 more Smart Citation

Thermo-Hydraulic Performance Analysis on the Effects of Truncated Twisted Tape Inserts in a Tube Heat Exchanger

Ghalambaz

Mashayekhi²,

Arasteh

et al. 2020

Symmetry

View full text Add to dashboard Cite

This paper investigates the convective heat transfer in a heat exchanger equipped with twisted tape elements to examine effects of the twisted tape truncation percentage, pitch value, position and Reynolds number using 3D numerical simulation. A symmetric heat flux is applied around the tube as the studied heat exchanger. Based on the influences in both heat transfer enhancement and pressure drop, the performance evaluation criterion (PEC) is utilized. Inserting twisted tape elements and reducing the pitch value significantly augment the Nusselt number, friction coefficient and PEC number compared to the plain tube. For the best case with a Reynolds number of 1000, the average Nusselt number increases by almost 151%, which is the case of fully fitted twisted tape at a pitch value of L/4. Moreover, increasing the twisted tape truncation percentage reduces both heat transfer and pressure drop. Furthermore, the highest heat transfer rate is achieved when the truncated twisted tape is located at the entrance of the tube. Finally, it is concluded that for P = L, L/2, L/3 and L/4, the optimum cases from the viewpoint of energy conservation are twisted tapes with truncation percentages of 75, 50, 50 and 0%, in which the related PEC numbers at a Reynolds number of 1000 are almost equal to 1.08, 1.24, 1.4 and 1.76, respectively.

show abstract

Section: Effect Of Twisted Tape Pitchmentioning

confidence: 83%

Section: Effect Of Truncated Twisted Tape Position and Percentagementioning

confidence: 83%

Thermo-Hydraulic Performance Analysis on the Effects of Truncated Twisted Tape Inserts in a Tube Heat Exchanger

Ghalambaz

Mashayekhi²,

Arasteh

et al. 2020

Symmetry

View full text Add to dashboard Cite

show abstract

“…The trends in the graphical representation for the values of Nu and f are in the acceptable range as per the co-relations given by Petukhov, Dittus-Boelter, Blasius and Gnielinsiki respectively [19]. The correlation given by Gnielinsiki and Dittus Boelter is given as; Dittus Boelter: = 0.023 × 0.8 × 0.4 (11) Gnielinsiki:…”

Section: Influence Of Angle Of Attackmentioning

confidence: 89%

“…The friction factor varies from 2.21 to 11.27 with enhancement in overall heat transfer performance from 1.17 to 6.15. Sarviya, et al [11] reported the experimental values for the twisted tape to insert with continuous rectangular cut edges with twist ratio 5 and 3 for Reynolds number 4000 to 20000. They observed the improvement in heat transfer rate by 2.21 and 2.23 times that of the smooth tube and 1.63 to 1.42 times of conventional twisted tape.…”

mentioning

confidence: 99%

Numerical and Experimental Investigations on Performance Evaluation of a Conical Offset Vortex Generator Inserts to Improve Convective Heat Transfer Coefficient

Mundhe

Bindu

2020

Journal of Thermal Engineering

View full text Add to dashboard Cite

The passive augmentation technique is widely used by researchers from thermal engineering field and it has shown excellent results for convective heat transfer rate. This paper shows the numerical and experimental findings for convective heat transfer characteristics and friction coefficient. Tests were conducted for turbulent flow, using air as medium through a uniformly heated steel pipe containing a novel kind of insert named as Conical offset Vortex Generator (COVG). The simulation tests were performed for turbulent flow with varying Reynolds number in the range 4000 to 50000. The parameters were analyzed during tests are pitch to smooth tube diameter ratio (p/d) and angle of attack (α). Various simulation tests were carried out with the help of ANSYS Fluent software to optimize the geometry. The simulation tests were carried out for different angle of attack (α = 15°, 30°, 60°). COVG with angle of attack (α = 60°) shows more enhancement in heat transfer rate, hence it was used for the experimentation purpose. The experimentation is conducted for various pitch to diameter (p/d = 1.18, 1.97, 3.94). The numerical and experimental results show improvement in heat transfer rate as there is decrease in pitch to smooth tube diameter ratio (p/d) and it also increases the value of friction factor. The reason behind the improvement in heat transfer rate is that, the braking of thermal boundary layer near the wall surface. Experimental results show the enhancement of Nusselt number from 3.46-6.7.

show abstract

“…Sarviya et al. 32 used continuous cut edges twisted tape and found significant heat transfer augmentation. Sharifi et al.…”

Section: Introductionmentioning

confidence: 99%

Experimental analysis on thermal and friction factor characteristics of fluid flow in tube with novel double strip helical screw tape

Chaurasia

Sarviya

2019

Proceedings of the Institution of Mechanical Engineers, Part A:

View full text Add to dashboard Cite

An experimental analysis has been carried out to investigate the thermal and friction factor characteristics of fluid flow in a tube with double strip helical screw tape (DS-HST) inserts with different values of twist ratio and compared with single strip helical screw tape inserts and plain tube. Water is used as a working fluid at different flow rates with constant heat flux conditions. CFD analysis is also carried out to visualize thermal and fluid flow characteristics of fluid flow in tube with inserts. Experimental results have showed that Nusselt number and friction factor have attained excellent enhancement with double strip helical screw tape inserts in the range of flow rates than single strip helical screw tape inserts at the value of twist ratio 1.5. Correlation is also developed for Nusselt number with a range of Reynolds number, twist ratio and number of strips. Moreover, the performance ratio has attained maximum value at twist ratio of 2.5 with high values of flow rate. It is concluded that DS-HST is able to attain enhancement in the efficiency of heat exchanger, causing a reduction in size for thermal applications.

show abstract

Heat Transfer and Pressure Drop in a Circular Tube Fitted with Twisted Tape Insert Having Continuous Cut Edges

Cited by 51 publications

References 13 publications

Thermo-Hydraulic Performance Analysis on the Effects of Truncated Twisted Tape Inserts in a Tube Heat Exchanger

Thermo-Hydraulic Performance Analysis on the Effects of Truncated Twisted Tape Inserts in a Tube Heat Exchanger

Numerical and Experimental Investigations on Performance Evaluation of a Conical Offset Vortex Generator Inserts to Improve Convective Heat Transfer Coefficient

Experimental analysis on thermal and friction factor characteristics of fluid flow in tube with novel double strip helical screw tape

Contact Info

Product

Resources

About