A proton exchange membrane fuel cell (PEMFC) system requires an adequate hydrogen supply and circulation to achieve its expected performance operating life. An ejector-based can reduce the maintenance costs, noise, parasitic power consumption by eliminating recirculation pump. However, ejector’s entrainment capability, restricted geometric parameters flow control variability, only operate prope...

In recent times, there has been a rise in popularity of comfort cooling systems, mainly based on electrically driven heat pumps. The accompanying peak loading on electricity grids is proving to be particularly problematic and expensive for electricity utilities, notwithstanding the greenhouse gas emissions associated with the electricity consumption of these het pumps. An alternative is to gene...

Integrating a two-phase ejector in mechanical vapor compression heat pumps is practical and low-cost solution for improving performance reducing energy consumption. Typically, using an to recover part of the important pressure expansion losses CO2 systems may improve operating conditions compressor. One prerequisites success such application proper design ejector. This study mainly dedicated de...

This paper presents a systematic comparison of ejector performance predictions between a thermodynamic model and a Computational Fluid Dynamics (CFD) model for different operating conditions. The thermodynamic model developed by Galanis and Sorin (2016) assumes the primary flow is always choked, and irreversibilities due to viscous dissipation are taken into account through polytropic efficienc...

BACKGROUND Needle cricothyrotomy and subsequent transtracheal jet ventilation (TTJV) is one of the last options to restore oxygenation while managing an airway emergency. However, in cases of complete upper airway obstruction, conventional TTJV is ineffective and dangerous. We transformed a small, industrial ejector into a simple, manual ventilator providing expiratory ventilation assistance (E...

Ever since the renaissance of transcritical R744 systems in the late 1980s, ejectors have been considered to improve energy efficiencies. However, the invention of the ejector dates back far longer. This review paper gives an overview of historical and recent developments regarding air-conditioning and refrigeration systems that use ejectors. More than 150 ejector papers available in the open l...

One of the issues that need to be addressed in order to improve the durability and efficiency of a PEM fuel cell system is the management of the hydrogen feeding procedure. It has been demonstrated these aspects are improved when a hydrogen recirculation systems are used [1]. In this work, an ejector has been designed and manufactured and implemented in an experimental PEM fuel cell Test Statio...

Many systems with liquid ejectors and centrifugal pump are known. Often, jet pumps used to provide a self-priming mode, as well an acceptable pressure level for cavitation-free operation. The main disadvantage of such is the relatively low efficiency associated peculiarities energy transfer in ejector. To increase double surface driving suction flow swirl (with circumferential component velocit...

In the recent times, the use of solar energy for the refrigeration purpose has been increasing day by day. Generally, solar used for cooling purpose has proposed many advantageous features in the refrigeration field. The cooling path is basically depends on the amount of solar radiation. The more amount of solar radiation directly increases the C.O.P. of the system. In this research paper, the ...

The wide-range ejector flowmeter is an active scavenging system applying calibrated gas removal directly to the anaesthetic circuit. The evacuation rate can be adjusted on the flowmeter under visual control using the calibration scale ranging from 200 ml X min-1 to 151 X min-1. The accuracy of the calibration was tested on three ejector flowmeters at 12 different presettings. The percentage dev...