Papers by Keyword: Compressor

Abstract: Vapour compression refrigeration is the most widely used method in domestic and commercial air conditioning and refrigeration systems. R22 (difluoromonochloromethane) is the most widely used HCFC (hydro chlorofluorocarbon) refrigerant in residential, commercial, industrial and transport cooling systems. Montreal protocol in 1987 banned the use of CFCs (chlorofluorocarbon) due to their adverse impact on the environment causing ozone depletion and global warming. HCFCs are also being phased out, though they are less destructive than CFCs. The present work explores compressor performance using alternate environment friendly working fluids so that R22 can be replaced in future. The refrigerants used for the studies are R134a (tetrafluoroethane), R290 (propane) and R600a (isobutane). Compressor performance is analysed by varying refrigerant mass flow rate, evaporator and condenser temperatures and studying their effect on compressor size, power and discharge temperature. A numerical simulation code has been developed in MATLAB using refrigerant properties taken from REFPROP.

Abstract: Aluminium used in beverage containers or cans is a sustainable material and can be recycled repeatedly. In Malaysia, the activities of collecting aluminium beverage cans for recycle normally involve a process of compressing aluminium cans manually in order to reduce storage space. The cans compression process is very time consuming and unproductive. In addition, there is no standard aluminium cans compressor tool that available in the market currently. As such, this paper aims to identify users requirements on the potential tool that could be used to compress aluminium beverage cans, follows by transform the important users requirements to a set of design criteria for the development of aluminium cans compressor. In line with this, six important factors that influence users purchase decision on household product were identified from literature review. The important factors were adapted into a questionnaire to collect and identify users preferred requirements on aluminium cans compressor via Voice of Customer technique. Subsequently, Pareto analysis and t-test were applied to define the most important and significant users requirements that influenced user purchase decision. As a result, a list of important users requirements is generated, which is also served as the design criteria for the development of a new aluminium cans compressor. Finding from the paper suggested that the most important design criteria for the potential aluminium cans compressor are consisted of safety, cost, performance and reliability requirements.

Abstract: With the exploitation of Jingbian Gas Field for decades, the formation energy gradually decreasing, and the wellhead pressure of some gas wells were found approaching to the pressure of gathering pipe network. Furthermore, some wellhead pressure can not make the produced natural gas get into the gathering pipe network. S well block of Jingbian Gas Field was set as the research object, applied numerical simulation method to create a new three dimensional geological model for gas reservoir of S well block, and then matched the reserves of gas reservoir and productivity parameters of gas well; applied the orthogonal test method design a variety of charging scheme and simulated every scheme; finally, decided an applicative pressurization scheme for gas well of S well block in Jingbian Gas Field.

Abstract: In this paper, the finite element model and mesh model of JQ40A gasoline engine turbocharger compressor was built by using Computational Fluid Dynamics(CFD) software NUMECA. The compression ratio and efficiency characteristics of compressor were simulated and verified experimentally. Based on the established models, the airflow velocity field, pressure field, temperature field and entropy field in the compressor volute passage and impeller clearance were simulated and analyzed. The simulation results show that the pressure loss is low and the flow passage design is reasonable; A rational volute export curvature R does not affect the compressor efficiency; the compressor impeller rim size can be adjusted to accommodate the engine torque characteristics; the engine speed affects internal loss of the flow field; within a certain range the impeller tip clearance is smaller, the higher the efficiency of the compressor is. The research methods and conclusions provide a basis for the optimization design of the compressor.

Abstract: The fundamental theory and simplified model of moving-magnet 1inear oscillating motor are presented in this paper. Based on the analysis of the equivalent magnetic and electric circuit model, a 2D finite element (FE) model of a linear oscillating motor with two separated stators is established. Through the FE simulation, the effect of the input voltage on the electric-magnetic force and displacement is investigated. The efficiency of the motor is estimated according to the analysis.

Abstract: Establish a CFD simulation interface for compressor aerodynamic analysis based on general CFD software. The simulation interface includes data format, process and interface standard. Data format based on CGNS is built for cross-platform restoring and retrieving mass data. The designing of process references the process of general CFD analysis and the compressor aerodynamic analysis. The interface standard is used to import and the parameters and export them into corresponding profiles according to the demand of different computation modules. Validation results for the simulation interface using a single-stage transonic axial compressor fan ATS-2 shows that the setting process is more convenient and achieves a certain degree of automation.

Abstract: Every compressor has a stall line. In the vicinity of the stall line, the flow field is inherently unsteady due to the interactions between adjacent rows of blades, formation of small stall cells, flow separation and the viscous effects including shock-boundary layer interactions. These factors may aggravate to a state of local breakdown of flow or a total breakdown of flow or with a disastrous flow reversal. This paper starts with an overview on the previous researches about compressor stall and surge. Subsequently, it describes the effects of these instabilities in overall engine performance and design with/ without any control. The main objectives of this paper are to review the phenomenon of instability and methodology to suppress the rotating stall and surge by enlarging the stable operating range of compressor with the application of various control systems. This paper surveys research developments in this field and also tries to find an improved solution to increase the engine performance by applying various surge control strategies. Finally, the paper focuses on some recommendations towards a better design of compressor especially for aircraft power plant.

Abstract: Electromagnetic control valve (ECV) controls an automobile vehicle air conditioning compressor based on a pulse width modulation (PWM) input signal that supplied from an external controller. For maintaining a suitable range of temperatures inside the vehicle, suction and crankcase port pressure controls the swash (wobble) plate at certain angle. Suction and crankcase port pressure controlled in ECV can be analyzed by experimental test by considering different technical assumptions. This research paper highlights the flow of air from crankcase port with correspondence with amount of variable supply of current to obtain the experimental test data which is important to maintain the vehicle temperature inside the compartment for passengers comfort.

Abstract: The development was made about the WW-1.65/7 oilless compressor in order to meet market demand. The oilless lubrication of the compressor is obtained by using self-lubricating materials and grease lubrication bearings. The reasonable structure of the piston component, its perfect seal effect and long life are achieved by the exact design and correct assembly. The air-cool pattern and the full opened crankcase bottom make the compressor cooled better, the cost is low. By analysis and calculation, the important structure parameters are made that the speed is 800r/min, the radius-length ratio is 1/6.6 and the axial width of the guiding ring is 50mm, these provide the important guarantee for the run reliability and life of the compressor. The WW-1.65/7 oilless compressor has better properties, can run reliably and go into mass production already.

Abstract: As a core component of a turbocharger, the efficiency of compressor directly affects its overall efficiency. The finite element model and mesh model of JQ40A turbocharger impeller is built by using Software Numeca in this paper. The compressor efficiency and the flow field with different inlet blade angle, the pressure surface boundary layer with different blade thickness are simulated in the case of the same outlet angle, throat area of and number of the blades. The result of the simulation and research shows that it is the inlet blade angle of 51.40 degrees and the average blade thickness of 0.5mm that make it the best design with highest efficiency .