Les paramètres géométriques optima d'un éjecto-compresseur frigorifique

Nahdi, E.; Champoussin, J. C.; Hostache, Gérard; Cheron, J.

doi:10.1016/0140-7007(93)90023-2

Cited by 40 publications

(7 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It was shown successively by Nahdi et al [63] and Eames et al [64], and by later research [47,86,87] that for fixed ejector compression and expansion ratios P b /P s and P p /P s respectively, an optimal value of ϕ exists for which the entrainment ratio ω is maximised.…”

Section: The Mixing Chamber Shape Effectsmentioning

confidence: 98%

“…Typically P p /P b , P p /P s and P b /P s are, respectively, motive, expansion and compression ratios. They are frequently used in ejector design diagrams and correlations [60,[63][64][65].…”

Section: Effect Of Inlet Pressuresmentioning

confidence: 99%

“…The NXP parameter indicates the positioning of the primary nozzle with respect to the mixing chamber. It is generally defined as the distance from the exit plane of the primary nozzle to the entry plane of the converging entrance zone of the mixing chamber [63] (Figure 3b). Others in some cases [70] consider the positioning of the primary nozzle relative to the inlet of the mixing chamber throat, especially in the case of constant area ejectors (Figure 3a).…”

Section: The Nozzle Exit Position (Nxp)mentioning

confidence: 99%

“…It is, however, still current in research for its flexibility and familiarity of use. It was common to model both fluids and other refrigerants as perfect gases or determine their properties by means of equations of state from the literature [63,192,193] and many others. Databases such as EES (Engineering Equation Solver) or NIST-REFPROP later became available to this purpose [41,265,266].…”

Section: Working Fluidsmentioning

confidence: 99%

See 3 more Smart Citations

Current Advances in Ejector Modeling, Experimentation and Applications for Refrigeration and Heat Pumps. Part 1: Single-Phase Ejectors

et al. 2019

View full text Add to dashboard Cite

Ejectors used in refrigeration systems as entrainment and compression components or expanders, alone or in combination with other equipment devices, have gained renewed interest from the scientific community as a means of low temperature heat recovery and more efficient energy use. This paper summarizes the main findings and trends, in the area of heat-driven ejectors and ejector-based machines, using low boiling point working fluids, which were reported in the literature for a number of promising applications. An overall view of such systems is provided by discussing the ejector physics principles, as well as a review of the main developments in ejectors over the last few years. Recent achievements on thermally activated ejectors for single-phase compressible fluids are the main focus in this part of the review. Aspects related to their design, operation, theoretical and experimental approaches employed, analysis of the complex interacting phenomena taking place within the device, and performance are highlighted. Conventional and improved ejector refrigeration cycles are discussed. Some cycles of interest employing ejectors alone or boosted combinations are presented and their potential applications are indicated.

show abstract

Section: The Mixing Chamber Shape Effectsmentioning

confidence: 98%

Section: Effect Of Inlet Pressuresmentioning

confidence: 99%

Section: The Nozzle Exit Position (Nxp)mentioning

confidence: 99%

Section: Working Fluidsmentioning

confidence: 99%

See 2 more Smart Citations

Current Advances in Ejector Modeling, Experimentation and Applications for Refrigeration and Heat Pumps. Part 1: Single-Phase Ejectors

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The ejector's performance is influenced by geometrical and thermodynamic parameters. According to various studies, the transition regime provides the best ejector performances [57,58,59]. Table 2 defines the various geometrical and thermodynamic parameters of the ejector.…”

Section: Ejector Modelingmentioning

confidence: 99%

Multi-Objective Optimization of a Solar Combined Power Generation and Multi-Cooling System Using CO2 as a Refrigerant

et al. 2023

View full text Add to dashboard Cite

This paper proposes a new combined multi-cooling and power generation system (CMCP) driven by solar energy. Carbon dioxide is used as a refrigerant. A parabolic trough collector (PTC) is employed to collect solar radiation and convert it into thermal energy. The system includes a supercritical CO2 power system for power production and an ejector refrigeration system with two ejectors to provide cooling at two different evaporating temperatures. The CMCP system is simulated hourly with weather conditions for Tunisia. The PTC mathematical model is used to calculate the heat transfer fluid outlet temperature and the performance of the CMCP system on a specific day of the year. A 1D model of an ejector with a constant area is adopted to evaluate the ejector performance. The system’s performance is evaluated by an energetic and exergetic analysis. The importance of the system’s components is determined by an exergoeconomic analysis. The system is modeled using MATLAB software. A genetic algorithm is used for multi-objective optimization to determine the best values and solutions for the system’s design parameters. The optimal energy and exergy efficiencies were found to be 13.7 percent and 37.55 percent, respectively, and the total product unit cost was 31.15 USD/GJ.

show abstract

Performance analysis of the vapour compression cycle using ejector as an expander

Nehdi

Kairouani

Bouzaina

2007

Int. J. Energy Res.

View full text Add to dashboard Cite

SUMMARYThe purpose of incorporating an ejector into vapour compression cycle is to improve the COP by reducing the throttling loss associated with the expansion device. A computer simulation of the improved cycle is carried out using a one-dimensional model based on mass, momentum and energy balances. Refrigerant characteristics were evaluated using NIST subroutines for equations of state solutions.According to the results of simulation of the improved cycle, it has been shown that the geometric parameters of the ejector design have considerable effects on the system's performance. The maximum COP is obtained for F opt whose value is around 10.Several refrigerants are considered; it has been observed, at F opt and for given operating conditions, that the best performances are obtained with R141b. Compared with the standard cycle the COP of the improved cycle shows an increase of about 22%.

show abstract

Les paramètres géométriques optima d'un éjecto-compresseur frigorifique

Cited by 40 publications

References 1 publication

Current Advances in Ejector Modeling, Experimentation and Applications for Refrigeration and Heat Pumps. Part 1: Single-Phase Ejectors

Current Advances in Ejector Modeling, Experimentation and Applications for Refrigeration and Heat Pumps. Part 1: Single-Phase Ejectors

Multi-Objective Optimization of a Solar Combined Power Generation and Multi-Cooling System Using CO2 as a Refrigerant

Performance analysis of the vapour compression cycle using ejector as an expander

Contact Info

Product

Resources

About