الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Compressed air applications have a share about 10% of the global industrial electric energy consumption and this share may reach 20% if commercial and residential needs are included. In order to accomplish global energetic commitment, energy saving is considered nowadays as an important action needed. The rotary compressors have advantages related to power consumption which is lower than that of rotodynamic compressors. Sliding-vane rotary compressors have considerable advantages in comparison with other positive displacement compressors in terms of volumetric efficiency, and continuity of flow without pulsations. However, sliding-vane rotary compressors have relatively low-pressure ratio. The current study presents a novel design of a two-stage sliding vane rotary compressor in an attempt to elevate the pressure ratio of that type of compressors. The proposed design for dual stage vane compressor is an extension to the patent published by Ahmed Shouman in 1999. The basic design features of this novel design are illustrated along with the adopted design geometry after examining the effects of several geometrical factors and their practicality. In addition, the study summarizes the design challenges encountered during its manufacturing in addition to the challenges to reduce inter-stage leakage and the applied solutions. After several trials, the first prototype of the two-stage sliding-vane rotary compressor has been manufactured and tested experimentally to evaluate its performance. The preliminary results of the flow rate, pressure rise and power consumption at different rotating speeds are reported in this study. The obtained results show that, the volumetric efficiency is lower in case of two-stage than single stage due to internal leakage and the mismatch between first stage discharge air flow rate and second stage suction cell volume. The performance of two-stage operation at discharge pressure 4 bar absolute shows lower inlet flow rate than that of single stage, this reduction is decreased from 40.3% to 33.4% as rotational speed increases. Mechanical power saving is increased from 1.6 % to 3.7% as rotational speed increases. While the performance of two-stage operation at discharge pressure 5 bar absolute shows lower inlet flow rate than that of single stage, this reduction decreases from 41.5 % to 33.9 % as rotational speed increases and mechanical power saving increases from 0.3 % to 2 % as rotational speed increases. Despite the several weak points observed in the performance of the first prototype of two-stage sliding vane compressor, the present results can be considered a good proof of concept of two stage sliding vane compressor design.