Experimental and numerical investigation of transient phenomena in vacuum ejectors

Jafarian, Ali; Azizi, Masoumeh; Forghani, Pezhman

doi:10.1016/j.energy.2016.02.101

Cited by 19 publications

(4 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In supersonic ejectors, the main task is to achieve the maximum vacuum level and increase the suction speed. Induced flow or secondary flow is air that passes through the second nozzle [9]. Analysis shows that the use of multistage vacuum ejectors is more preferable in comparison with single-stage and allows you to create a higher vacuum in a low-pressure nozzle [10].…”

Section: Introductionmentioning

confidence: 99%

Aerodynamic study of an ejector in a modernized device for thermal vacuum extrusion of food products

Frolov

Kurochkin

2022

IOP Conf. Ser.: Earth Environ. Sci.

View full text Add to dashboard Cite

The present study is aimed at the modernization of a device for processing food wet materials using vacuum extrusion. It is proposed to modernize the device by adding an ejector, a chamber for preliminary and final dehydration. Steam is removed from the final dewatering chamber using a vacuum pump. An ejector installed after the vacuum pump allows steam to be removed from the pre-dehydration chamber. The Solidworks FlowSimulation package was used to build and simulate the ejector. The air flows inside the ejector were investigated to obtain data on the required performance of the vacuum pump and to display the distribution of air flows and pressures. The images of the pressure distribution inside the ejector and the pressure at the inlet to the low-pressure nozzle were obtained. A model of an ejector with an initial volumetric flow rate of 4 m3/h and 8 m3/h for an incoming high-pressure flow is considered. The results show that it is sufficient to use a vacuum pump with a capacity of 4m3/h to remove the generated steam. The modernization of the device increases the energy efficiency of the technology for processing plant raw materials and simplifies technological adjustments.

show abstract

Section: Introductionmentioning

confidence: 99%

Aerodynamic study of an ejector in a modernized device for thermal vacuum extrusion of food products

Frolov

Kurochkin

2022

IOP Conf. Ser.: Earth Environ. Sci.

View full text Add to dashboard Cite

show abstract

“…Within this type, there are two categories: the constant-area mixing ejector [2,3] and the constant-pressure mixing ejector. A great amount of literature has been published on the latter category, for example [4,5].…”

Section: Introductionmentioning

confidence: 99%

Multi-Factor Design for a Vacuum Ejector Improvement by In-Depth Analysis of Construction Parameters

Macia¹,

Castilla²,

Gamez-Montero³

et al. 2022

Sustainability

View full text Add to dashboard Cite

A vacuum supersonic ejector is an indispensable pneumatic device placed in nearly all industrial production lines. This device, also called a zero-secondary flow ejector, is characterized by the maximum entrained flow and the minimum secondary pressure. Numerical simulations were carried out by means of the CFD toolbox OpenFOAM v8 and its solver HiSA, which uses the AUSM+up upwind scheme. A single-factor analysis of eight parameters was performed to find how the ejector’s performance was enhanced or decreased, while other parameters were fixed. Four parameters were subject to further analysis to find the geometry that improves the standalone performance of the ejector. The mixing chamber length is the parameter that most improves its performance; alone it leads to a 10% improvement. A multi-factor analysis, based on a fractional factorial design, is carried out with the four relevant parameters. Results indicate that the multi-factor analysis enhances the performance of the ejector by 10.4% and the mixing chamber length is the factor that most influences the improvement. Although a multi-factor design improves the performance, no significant relevance has been detected with respect to the mixing chamber length improvement alone. The improved performance of this device leads to a reduction in operating time and, as a consequence, results in significant energy savings.

show abstract

“…Due to its simple structure, a jet pump is used to transport the majority of working media, and it is especially suitable for dredged soil transport [4][5][6]. Its working principle is transferring mass and heat through turbulent diffusion between the primary and secondary flows [7]. The advantages of reliable operation, low cost and easy maintenance [8] make it widely used in many industrial fields, such as the refrigeration industry [9], water conservancy engineering [10], aerospace engineering [11], chemical industry [12] and fish farming [13].…”

Section: Introductionmentioning

confidence: 99%

Numerical Investigation of the Flow Field and Mass Transfer Characteristics in a Jet Slurry Pump

et al. 2021

View full text Add to dashboard Cite

A jet pump is used to transport a variety of working media and is especially suitable for dredged soil transporting. In this study, a three-dimensional numerical study of a jet pump that is used for slurry delivery was carried out. The characteristics of the internal flow field of the mixing chamber with different working parameters were comprehensively analyzed. The results indicate that the pressure of the axial line decreases with increasing flow ratio (ratio of suction flux and inlet flux) while the pressure of the injected slurry shows a downward trend. With the increase in the flow ratio, the pressure ratio (difference between inlet pressure and suction pressure divided by the difference between exit pressure and suction pressure) falls off while the efficiency presents a parabolic distribution. The pressure ratio can be promoted by properly increasing the length of the mixing chamber so that the available efficiency is broadened. When the mixing chamber length is L = 2.5Dn~4.0Dn (Dn is nozzle outlet diameter), the highly efficient area is wide; in particular, when L = 3.5Dn, the jet slurry pump with the highest efficiency of 27.6% has the best performance.

show abstract

Experimental and numerical investigation of transient phenomena in vacuum ejectors

Cited by 19 publications

References 31 publications

Aerodynamic study of an ejector in a modernized device for thermal vacuum extrusion of food products

Aerodynamic study of an ejector in a modernized device for thermal vacuum extrusion of food products

Multi-Factor Design for a Vacuum Ejector Improvement by In-Depth Analysis of Construction Parameters

Numerical Investigation of the Flow Field and Mass Transfer Characteristics in a Jet Slurry Pump

Contact Info

Product

Resources

About