The Port Width and Position Determination for Pressure-Exchange Ejector

Abstract

A pressure-exchange ejector transferring energy by compression and expansion waves has the potential for higher efficiency. The width and position of each port are essential in pressureexchange ejector design. A dimensionless time x expressing both port widths and the positions of port ends was introduced. A prototype was designed and the experimental system was set up. Many sets of experiment with different geometrical arrangements were conducted. The results suggest that the efficiency greatly changes with the geometrical arrangements. The efficiency is about 60% at proper port widths and positions, while at improper geometrical arrangements, the efficiency is much lower and the maximum deviation may reach about 20%. The proper dimensionless port widths and positions at different operating conditions are obtained. Eor a flxed overall pressure ratio, the widths of the high pressure flow iniet and middle pressure flow outlet increase as the outlet pressure increases and the low pressure flow inlet width is reduced with a larger outlet pressure. The middle pressure flow outlet (MO) opening end remains constant at different outlet pressures. The positions of the high pressure flow inlet (HI) closed end and the low pressure flow inlet (LI) open end increase with the elevation of outlet pressure, however, the distance between the HI closing end and the Ll opening end is constant. The port widths and positions have a signiflcant influence on the performance of the pressure-exchange ejector. The dimensionless data obtained are veiy valuable for pressure-exchange ejector design and performance optimization.

Performance experiments with a gas wave ejector equipped with curved channels and an analysis of the influence of channel angles

“…This can help to reduce the overall structure size and the manufacturing and operating costs of this system by nearly 50%. Hu et al [27][28][29] of Dalian University of Technology began to conduct in-depth numerical and experimental research on GWEs based on their extensive experience in the area of gas-wave technology. [24][25][26] They obtained the complete performance curves of GWEs equipped with straight rotor channels 30 and determined the laws governing the effects of parameters such as rotational speed on equipment performance.…”

“…However, since all existing gas ow and gas wave theories related to GWEs are based on equal-section straight rotor channels, the GWE devices investigated by various institutions are all equipped with straight channels. 20,27 According to the relevant studies, there is large ow loss in straight channels during the gas injection process. 31,32 Furthermore, the viscous dissipation of gas and other ow losses can be promoted due to the medium-pressure gas being exhausted along the rotor rotational direction.…”

Numerical Simulation Research on the Effect of the Rotor Passage Cross-Sectional Dimension on the Performance of Gas Wave Ejector

“…In the 2000s, Kharazi et al [6] from the University of Michigan proved that GWE might replace the condenser and the first-stage compressor in the R718 refrigeration cycle, resulting in a 50% reduction in the system investment. In the 2010s, Hu et al [7] of Dalian University of Technology (DUT) started to study on GWE and obtained the influence of several structure and operating parameters on its performance [8].…”

Study on the Performance of Collaborative Production Mode for Gas Wave Ejector

“…As a result, it has been considered for application in a variety of fields, such as the exploitation of natural gas, refrigeration cycles, and so on [16][17][18][19]. Due to the issues of both devices mentioned above, the gas wave ejector (GWE) [10] which combines the benefits of expansion-compressor units and static ejector has received more and more attention. Similar to other wave rotor technologies [11][12][13][14][15], the core components of GWE, as shown in Figure 2, are a wave rotor made up of uniformly distributed channels and the end plates with pressure ports on both sides of the rotor.…”

“…Since 2010, Hu. et al [10,27] from Dalian University of Technology have been conducting further theoretical and experimental research on GWE technology. The group of Hu.…”