Efficiency Measurement of Compressed Air Compressors Using High Availability SoC with 1oo2 Redundancy Architecture

Compressed air systems are essential components in various industrial and everyday applications. The efficiency of these systems is very important due to their role in the energy consumption of industrial plants. To increase efficiency, a new concept for compressed air compressors based on Industry 4.0 is presented. Due to the aggressive environmental conditions in which the compressed air compressors operate, a new design of a SoC with high availability based on 1oo2 redundancy architecture is developed.

Findings from Measurements of the Electric Power Demand of Air Compressors

The compressed air electric ratio (CAER) describes the ratio of the real electric power demand to the nominal mechanical power of an air compressor. The CAER is an important indicator as the electric power demand of air compressors varies throughout its operation dependent on compressor technology, pressure ratio, and free air delivery. The nameplate power of the compressor drive motor is not sufficient for evaluating the electric power demand; therefore, the CAER plays an important role in assessing the electric operating power demand. In this paper, results from measurements of fixed speed and variable speed (VFD) compressors are presented with the analysis of key influencing factors of the CAER. The data show that the pressure ratio of operating pressure to the maximum design outlet pressure has the largest impact on the CAER. For VFD compressors, the CAER is represented as a linear function dependent on the respective load. Fixed and variable speed compressors’ CAERs are always dependent on the load condition. In idle condition, the CAER was measured to be 0.2. In full load condition with a pressure ratio of 0.6, the CAER averages at a value of 0.87, meaning a 90 kW compressor at 0.6 pressure ratio draws 78.3 kW electric power.

METHODOLOGY FOR THE UTILIZATION OF WASTE HEAT BY AIR-COOLED COMPRESSORS

Compressed air is still a valid helper in many applications today, where it is necessary, for example, to move work equipment, pistons or it is used for cooling as a cooling medium. The producer of compressed air are air compressors, which need an external source for its production, usually an electric or internal combustion engine. Almost all the energy that is supplied to the compressor is always converted to heat during compression, regardless of the type of compressor. This carries the risk of overheating and therefore the cooling system must be optimally designed. Thus, during the compression of the air, a large part of the electrical energy supplied to the compressor is converted into heat, and only a small part of the supplied energy is in the compressed air. In the case of oil or water-cooled compressors, the exchangers can be used directly to obtain energy "for free". In the case of air cooling, a slight energy gain can only be achieved by modifying the exhaust hot air ducts. This energy can be used efficiently to heat water or heat buildings, instead of being uselessly ventilated. Modern compressors are already adapted for the use of waste heat, but most current companies still use older types of compressors that have not been directly adapted for the use of waste heat. In case of interest in obtaining waste heat, the reconstruction of the facility or development is inevitable.

Energy, Exergy, and Emission Analysis on Industrial Air Compressors

Air compressors, a key fluid power technology, play an important role not only in industrial plants but also in office buildings, hospitals, and other types of facilities. The efficient use of the air compressor is crucial to control unnecessary inefficiencies that cause high energy consumption. This study aims to provide energy and exergy analysis on air compressors for different industries. Detailed case studies are also analyzed. The case study focuses on the energy and exergy analysis of the compressed air system of foundry industries. The results indicate that applying the six improvement recommendations yield significant amounts of energy and cost savings as well as significant improvements in the overall performance of the system. The payback periods for different recommendations are economically feasible and worthwhile to use. The suggested improvement methods can provide high costs with a low payback period.

Selection of marine type air compressor by using fuzzy VIKOR methodology

Ships have to maintain many auxiliary machineries with high power consumption, and these machineries generally run continuously for long hours. One of the auxiliary machineries that consume a lot of power in ships is the air compressor. These air compressors are especially important as they are used at the start of the main engine and generator diesel engines. Therefore, a suitable selection of these compressors is vital, in terms of technical requirement, energy efficiency, and cost effectiveness. The main focus of this study is to decide the optimum compressor in terms of all technical and operational criteria. In this context, using the fuzzy VIKOR method, five different and worldwide known compressor brands are listed in terms of selection by evaluating seven different and important criteria. These criteria were evaluated by five experts working as technical directors in shipping companies without being informed of each other. Briefly, this study aims to assist shipping companies in choosing the optimal compressor to suit their primary operating goals, considering the navigating routes and conditions of commercial ships. We believe that it is possible to close this gap in the literature and to select the optimum compressor according to the technical and operational needs.

3D transient numerical simulation of a helical roots air compressor for FCVs

Oil-free helical Roots air compressors which have great application potential in air circulation systems for high-power fuel cell systems, such as commercial fuel cell vehicles (FCVs), have the advantages of active adaptation, low cost, large flow rate and high reliability. In this study, a three-dimensional transient numerical simulation model of a helical Roots air compressor was established by considering all leakage clearances. In this study, hexahedral structured dynamic grids were generated in the working chamber and the rotating angle was updated at an increment of 1° to ensure the mesh quality of the entire solving domain. The accuracy of the simulation model was validated using experimental data, and the maximum deviation was less than 4.0%. Based on the simulated results, the pressure field and variation of the pressure field with the rotation angle are presented. It shows that the pressure fluctuation at the discharge side was larger than that at the suction side. The influence of various leakage clearance on the volumetric efficiency was analyzed comparatively. Additionally, the flow field characteristic of clearance was revealed. It is found that the rotor tip clearance was the major factor for the reduction of volumetric efficiency when the size was larger than 0.12 mm instead of the interlobe clearance. It is suggested that more attention should be paid to control the clearance size to ensure the performance of helical Roots air compressors.