Heat transfer and pressure loss in swirl tubes with one and multiple tangential jets pertinent to gas turbine internal cooling

Rao, Yu; Biegger, Christoph; Weigand, Bernhard

doi:10.1016/j.ijheatmasstransfer.2016.10.119

Cited by 51 publications

(9 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The average Nusselt numbers for the four turbulence models are presented in difference. This latter figure is close to the results of [35], where the difference between SST predicted values and measured values of average Nusselt numbers ranged between 8% and 13%. The RNG kε model was adopted for all the following calculations, not only because of its ability to predict the heat transfer and velocity profiles more accurately, but also its low computational cost.…”

Section: Validationsupporting

confidence: 89%

Numerical investigation on heat transfer performance and flow characteristics in a roughened vortex chamber

Alhajeri

Almutairi

Alenezi

et al. 2019

Applied Thermal Engineering

View full text Add to dashboard Cite

In this study, an investigation of a vortex chamber was carried out to gain a full understanding of the nature of the vortex flow and the cooling capability inside the chamber. The paper discusses the effects on flow and heat transfer rates when the inside surface of the vortex chamber was roughened by adding flow turbulators to its wall. The turbulators took the shape of a rib with a square cross-section, the dimension of which varied between 0.25 mm and 2.00 mm. The paper also presents the results of a comparative investigation of jet impingement and vortex cooling on a concave wall using different parameters, such as the total pressure loss coefficient, Nusselt number and thermal performance factor, to evaluate the cooling effectiveness and flow dynamics. Furthermore, the entropy generation in swirl flow with the roughened wall was assessed over a wide range of Reynolds numbers.The results show that surface roughness considerably influences the velocity distribution, heat transfer patterns and pressure drop in the vortex chamber. The highest thermal performance factor takes place at rib heights of 0.25 mm and 0.50 mm with a low Re number. Further increase in rib height has an adverse impact on thermal performance. At a Reynolds number lower than 50000, it is highly recommended to use roughened vortex cooling to obtain the best thermal performance.

show abstract

Section: Validationsupporting

confidence: 89%

Numerical investigation on heat transfer performance and flow characteristics in a roughened vortex chamber

Alhajeri

Almutairi

Alenezi

et al. 2019

Applied Thermal Engineering

View full text Add to dashboard Cite

show abstract

“…And they also explained the flow and heat transfer characteristics of swirl tubes with single tangential jets are significantly different from those with multi-tangential jets. The swirl heat transfer tube with multiple tangential jets shows more practical performance and can achieve stronger and more uniform heat transfer distribution [25]. In addition, Liu et al [26], Biegger et al [24], and Bruschewski et al [27] have conducted numerical simulations of swirling flow in a tube using RANS (Reynolds averaged numerical simulation), DES (detached eddy simulation), and LES (large eddy simulation) and obtained flow field results that matched the experimental heat transfer results.…”

Section: Introductionmentioning

confidence: 86%

“…Figure 2 provides a schematic of the computational geometry of anti-icing inner fluid, where the circular tube has a length of 1000 mm and a diameter of 50 mm, conforming precisely to the specifications outlined in Ref. [25]. The hot air is extracted from engine compressor and passes through five holes to reach the inner anti-icing surface, and the five holes are of three types, which are the impingement jets, offset jets, and swirl jets.…”

Section: Numerical Setupsmentioning

confidence: 99%

Investigations on Hot Air Anti-Icing Characteristics with Internal Jet-Induced Swirling Flow

Liu,

2024

Aerospace

View full text Add to dashboard Cite

The tangential jet-induced swirling flow is a highly efficient technology for enhancing heat transfer. This paper explores the application of swirling flow of an airfoil/aero-engine in a hot air anti-icing chamber, aiming to improve the anti-icing performance and achieve a more uniform temperature on the surface. A series of numerical computations adopting the SST k − ω turbulent model was carried out to obtain the internal flow and heat transfer characteristics, as well as the surface temperature distributions, considering water evaporation and solid heat conduction. Three jet arrangements, including impingement jets, offset jets, and swirl jets, were studied and compared, which evidently showed that the swirling effect was helpful to elevate the internal heat transfer. Compared to the impingement jets at the Reynolds number of 40,000, the Nusselt number with the offset jets is increased by 19.5%, while the corresponding Nusselt number of the swirl jets is augmented by 44.3%. The swirling flow significantly elevates the swirl number within the internal chamber, intensifying the vortex strength near the wall and increasing the circumferential velocity, which also results in an augmentation of internal pressure loss. By adopting the swirling internal flow, the temperature distribution on the anti-icing surface is more uniform and is increased by up to about 4.1 K in the leading edge when the internal-to-external temperature difference is 80 K. Simultaneously, the heat absorption of water evaporation and the matches between the internal heat transfer and external icing load are of particular importance to determine the anti-icing performance, and this has been discussed in this paper.

show abstract

“…Experimental work on the behavior of a shell‐tube exchanger was performed by Ghorbani et al 19 It was shown that flow rate was the main factor in temperature behavior along the system. Rao et al 20 investigated experimentally the effect of single and double tangential jets relevant to gas turbine internal cooling and pressure loss. Findings showed that two different inlet jet modes possess different heat transfer patterns.…”

Section: Introductionmentioning

confidence: 99%

Experimental study on heat transfer augmentation in a double pipe heat exchanger utilizing jet vortex flow

2022

View full text Add to dashboard Cite

This paper examines experimentally the effect of jet vortex technology on enhancing the heat transfer rate within a double pipe heat exchanger by supplying the heat exchanger with water at different vortex strengths. A vortex generator with special inclined holes with different inlet angles was designed, manufactured, and integrated within the heat exchanger. In this study, four levels of Reynolds number for hot water in the annulus (Reh) were used, namely, 10,000; 14,500; 18,030; and 19,600. Similarly, four levels of Reynolds number for cold water in the inner tube (Rec) were used, namely, 12,000; 17,500; 22,500; and 29,000. As for the inlet flow angle (θ), four different levels were selected, namely, 0°, 30°, 45°, and 60°. The temperature along the heat exchanger was measured utilizing 34 thermocouples installed along the heat exchanger. It was found that increasing the inlet flow angle (θ) and/or the Reynolds number results in an increase in the local Nusselt number, the overall heat transfer coefficient, and the ratio of friction factor. It is revealed that the percentage increase in the average Nusselt number due to swirl flow compared to axial flow was 10%, 40%, and 82% for an inlet flow angle of 30°, 45°, and 60°, respectively.

show abstract

Heat transfer and pressure loss in swirl tubes with one and multiple tangential jets pertinent to gas turbine internal cooling

Cited by 51 publications

References 18 publications

Numerical investigation on heat transfer performance and flow characteristics in a roughened vortex chamber

Numerical investigation on heat transfer performance and flow characteristics in a roughened vortex chamber

Investigations on Hot Air Anti-Icing Characteristics with Internal Jet-Induced Swirling Flow

Experimental study on heat transfer augmentation in a double pipe heat exchanger utilizing jet vortex flow

Contact Info

Product

Resources

About