CFD analysis of helical nozzles effects on the energy separation in a vortex tube

Pourmahmoud, Nader; Zadeh, Hassan Amir; Moutaby, Omid; Bramo, Abdolreza

doi:10.2298/tsci110531085p

Cited by 41 publications

(16 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All of mentioned investigations reported that the shape of inlet nozzles should be designed such that the flow enters tangentially into the vortex chamber. Pourmahmoud et al [19,20] numerically investigated the effect of helical nozzles on the performance and the cooling capacity of a vortex tube. They also introduced a new parameter named GPL (nozzle inlet gap per length of nozzle) to design this kind of nozzles.…”

Section: Figure 1 Schematic Drawing Of a Vortex Tubementioning

confidence: 99%

Numerical Simulation of Effect of Shell Heat Transfer on the Vortex Tube Performance

Pourmahmoud¹,

Abbaszadeh²,

Rashidzadeh³

2016

IJHT

Self Cite

View full text Add to dashboard Cite

Since, cooling is the main use of vortex tube, the exited heat from the hot outlet of vortex tube can be assumed as the wasted energy when it is used as a cooling device. So, this paper tries to reduce the hot and cold temperatures at exhausts in order to increase the vortex tube cooling power. In this paper, a new method is studied which uses the shell heat transfer mechanism to affect the flow pattern inside the vortex tube. This research tries to clarify the flow pattern inside the vortex tube applying a fixed negative heat flux on the wall of the vortex tube. The results indicate that a part of main tube (around 23%) can be introduced as the effective cooling length.

show abstract

Section: Figure 1 Schematic Drawing Of a Vortex Tubementioning

confidence: 99%

Numerical Simulation of Effect of Shell Heat Transfer on the Vortex Tube Performance

Pourmahmoud¹,

Abbaszadeh²,

Rashidzadeh³

2016

IJHT

Self Cite

View full text Add to dashboard Cite

show abstract

“…Bramo & Pourmahmoud 15 numerically examined the effect of length-to-diameter ratio (L/D) and stagnation point position on the temperature separation. Pourmahmoud et al 16,17 analyzed the effect of number and shape of nozzles on the vortex tube behavior. They found that applying the helical nozzles leads to higher swirl velocity and temperature difference, as compared to the straight nozzles.…”

Section: Open Accessmentioning

confidence: 99%

CFD Analysis of Temperature Separation in a Convergent Vortex Tube

Rashidzadeh¹

2016

IPCSE

View full text Add to dashboard Cite

The purpose of this paper is to investigate the effect of using a convergent hot tube on the vortex tube refrigeration capacity. The computational fluid dynamics (CFD) model used is a three-dimensional steady compressible model that utilizes the k-ɛ turbulence model. In this numerical research, different convergence angles of the hot tube (β=0°, 0.5°, 0.88°, 1°, 1.5°, and 2°) have been considered to analyze the vortex tube performance. The results showed that as the angle converges from the cylindrical model (β=0°), the cold temperature separation improves at the cold mass fractions greater than about 0.3, but increasing the angle more than 2° impairs the cold temperature separations compared to the cylindrical model, because of the secondary circulation development inside the vortex tube. Also, a successful validation has been carried out between some available experimental results and the present numerical model (for cylindrical vortex tube) IntroductionThe vortex tube is a simple device, without any moving parts, that separates a pressurized flow of air (or any inlet gas) into hot and cold streams. Compressed air enters tangentially into the vortex chamber, where it splits into two lower pressure streams, the peripheral and the inner vortexes. The hot stream rotates near the outer radiuses (near the wall) while the cold stream flows at the center of the tube. The hot outer layers of the compressed gas escape through the conical valve side at the end of the tube. The remaining gas returns in an inner vortex and leaves through the cold exit orifice located at the other end of the tube near the inlets. This behavior is schematically illustrated in Figure 1. There are various explanations for this behavior happened in the vortex tubes. One explanation is that, owing to centrifugal force, the outer air is under higher pressure than the inner air. So, the temperature of the outer layers is higher than that of the inner layers. Another explanation is that as both vortices have the same angular velocity and direction, the inner vortex loses angular momentum.

show abstract

“…Nader POURMAHMOUD et al [6] investigated the effect of helical nozzles on temperature separation of RHVT. They used 3-D steady-state axisymmetric computational domain along with periodic boundary conditions for analysis, utilizing both straight and helical nozzles.…”

Section: Numerical Studies On Rhvtmentioning

confidence: 99%

A Review of Computational Studies of Temperature Separation Mechanism in Vortex Tube

Thakare¹,

Patil²,

Parekh³

2013

BIJIEMS

View full text Add to dashboard Cite

show abstract

CFD analysis of helical nozzles effects on the energy separation in a vortex tube

Cited by 41 publications

References 16 publications

Numerical Simulation of Effect of Shell Heat Transfer on the Vortex Tube Performance

Numerical Simulation of Effect of Shell Heat Transfer on the Vortex Tube Performance

CFD Analysis of Temperature Separation in a Convergent Vortex Tube

A Review of Computational Studies of Temperature Separation Mechanism in Vortex Tube

Contact Info

Product

Resources

About