Papers by Keyword: Single Screw

Abstract: Renewable energy has become a promising alternative energy due to innovations that have reduced costs and realized the future of environmentally friendly energy. Hydroelectric power plants are one of the most promising renewable energy in Indonesia, especially in areas with many rivers. In many low head water flow locations, Archimedes Screw Turbine (AST) may be more cost-effective, with lower installation and operation costs than alternative hydroelectric power systems. Although many theoretical and experimental investigations have been published regarding the implementation of this AST over the past decade, there has been no experimental evaluation in the literature for heads below 1 meter. This post presents test results from Single Screw Archimedes turbine with a difference in flow rate of 106 l/min, 291 l/min, 594 l/min, and 1035 l/min and head variations of 0.7 meters, 0.8 meters, 0.9 meters, and 1 meter. Maximum turbine power of 93.93 Watt at 1035 l/min at head 0.7 meters. The results provide new insights into the performance of the Archimedes screw turbine efficiency under the 1-meter head. The flow rate is comparable to torque and power increases as the turbine entry flow increases.

Abstract: In injection moulding or in extrusion, plastication is the step during which polymer pellets are melted by the means of mechanical dissipation provided by a rotating screw and by thermal conduction coming from a heated metallic barrel. This step is crucial for melt thermal homogeneity, charge dispersion and fibre length preservation. Although there have been a large number of theoretical and experimental studies of plastication during the past decades, mostly on extrusion and mostly using the screw extraction technique, extremely few of them have dealt with trying to visualise plastication, let alone measuring the plastication profile in real-time. As a matter of fact, designing such an equipment is an arduous task. We designed an industry-sized metallic barrel, featuring 3 optical glass windows, each window possessing 3 plane faces itself to allow for visualisation and record by synchronised cameras and lightening by lasers. The laser can be used in a laser induced fluorescence or in a particle imaging velocity measurement framework. The images recorded can be further analysed by digital image processing. Preliminary results confirm the plastication theory and show a compacted solid bed and a melt pool side by side. The total plastication length is a direct function of screw rotation frequency as it is obvious from results on the melt pool width, which increases when the screw rotation frequency decreases. However, some evidence of solid bed breakage has been recorded, whereby the solid bed does not diminish continuously along the screw but is fractured in the compression zone These experimental findings are compared to predictions by a one-dimensional model of plastication

Abstract: Prepare poly butylene terephthalate (PBT)/multi-walled carbon nanotubes (MWNTs) composites through the method of melt blending. Then use low-cost single screw extruder to conduct experimental research and analysis on the extrusion test sample of PBT/MWNTs composites of different proportions under the conditions of changing the extrusion temperature, rate, cooling mode and so on. As a result, the process parameters of the better extrusion temperature, critical extrusion rate, and high-gloss molding etc. to reinforce the electrical properties of composites under low-cost experiment condition have been obtained. The experiment results also indicate that with the increasing of the MWNTs content, the surface resistivity of the composites shows a declining trend.

Abstract: The physical, mathematical and finite element model of the extruding part of mixing-extruding machine was established to carry on the finite element simulation of the extrusion part flow field. Results showed that the double cone screw have better mixing and feeding properties than single screw.