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Sample Preparation Techniques to Isolate and Recover Organics and Inorganics
Published in Paul R. Loconto, Trace Environmental Quantitative Analysis, 2020
This author has and continues to be fascinated with the magnetic stirrer/stir-bar device that has been available to laboratories for over 30 years. A Teflon-coated stir bar is dropped into a beaker that is approximately half filled or less with a liquid, the power is turned on, and a vortex is created within the liquid. This swirling vortex greatly facilitates mixing.
Force-System Resultants and Equilibrium
Published in Richard C. Dorf, The Engineering Handbook, 2018
Vortex - A flowfield in which fluid elements rotate about a common axis. In a vortex where viscous effects are not important, the velocity at which a fluid element circles the axis is inversely proportional to its distance from the axis.
Pumped systems
Published in David Butler, Christopher Digman, Christos Makropoulos, John W. Davies, Urban Drainage, 2018
David Butler, Christopher Digman, Christos Makropoulos, John W. Davies
Axial-flow pumps are simpler than centrifugal pumps and have impellers (acting like a propeller) that force the liquid in the direction of the longitudinal axis (Figure 14.8). Axial flow pumps are suited to relatively high flow rates and low heads with efficiencies of 75%–90%. Unlike centrifugal pumps, axial-flow pumps suffer a rapid decrease in head with increased discharge. In mixed-flow pumps, the direction in which the water is forced by the impeller is at an intermediate angle, so flow is partially radial and partially axial. Mixed-flow pumps are recommended for medium heads between 6 and 18 m and are capable of pumping flows up to 10,000 L/s. Axial- and mixed-flow pumps are most appropriate for pumping stormwater. Vortex pumps are used to handle high solids/grit load where the impeller creates a vortex beyond the volute and into the surrounding water. This helps gather up the solids, including fibrous and stringy material, without coming into contact with the impeller or blocking it. These are relatively low-flow, low-head pumps and are ideal for applications such as providing protection against flooding for individual properties while having the ability to discharge into the downstream system. Figure 14.9 illustrates the shape of pump characteristics for the main types of pumps. In practice, pump selection for a particular application is made by matching requirements to manufacturer's data.
Computational analysis for temperature separation and correlations prediction for dual-inlet-sections vortex tube
Published in Numerical Heat Transfer, Part B: Fundamentals, 2023
Ravi Kant Singh, Achintya Kumar Pramanick, Subhas Chandra Rana
A vortex tube is a device that separates compressed gas into hot and cold streams by utilizing the principles of fluid dynamics. It was invented in 1930 by George Ranque [1], a French physicist. The vortex tube operates by directing compressed gas tangentially into a chamber, where it creates a vortex motion that separates the gas into two streams. One stream is hot, and the other is cold. The hot stream exits the vortex tube from one end, while the cold stream exits from the other end. The vortex tube has many industrial applications, including cooling electronic components and machining tools, as well as heating and drying processes. One of its advantages is that it doesn’t require any moving parts or electricity to operate, making it a reliable and cost-effective solution for many industries. Despite its usefulness, the vortex tube has some limitations, such as limited cooling capacity and sensitivity to variations in gas flow and pressure. Nonetheless, it remains an essential tool in various industries and continues to be a subject of research and development. Skye et al. [2] examined the performance of the VT under varying mass fraction and intake pressure conditions, utilizing both experimental and numerical approaches. According to their findings, the cold temperature decreases with an increase in intake pressure.
The pulsatile 3D-Hemodynamics in a doubly afflicted human descending abdominal artery with iliac branching
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2023
Sumit Kumar, S. K. Rai, B.V. Rathish Kumar, Om Shankar
Next, a further investigation is made into the flow field. Figure 14 illustrates the three-dimensional vortex core iso-surface at T3 and T6 instants of the cardiac cycle. A vortex is instinctively understood as the swirling motion of fluid around a central region of the fluid domain. It is a well-known fact that the amount of vorticity shows energy concentration, circulation conditions and spatial condition of blood dynamics (Contijoch et al. 2020). Figure 14 shows that iso-vorticity surface dominant at the peak of systole T3 gets drastically reduced and almost negligible, especially in the region distal to RIIAS by the late systolic period (T6). Such a feature indicates loss in vorticity due to vortex shedding as depicted earlier in the flow field.
Review of vortex tube: a sustainable and energy separation device for multi-purpose applications
Published in Australian Journal of Mechanical Engineering, 2023
A major processing step when treating hydrocarbon gas is the removal of components such as heavy hydrocarbons or water. This occurs due to recovery of saleable liquids or prevents hindrance during gas transportation (e.g. hydrate formation or two-phase flow). The vortex tube device contributes to a extensive range for the equipment to be available for this application. Vortex tube equipment has been used for improved separation with the advantage dependent upon the inlet conditions of the gas and available pressure drop. An optimum pressure drop of 25–35% of the inlet gas pressure has been confirmed in practice (Lorey, Steinle, and Thomas 1998). It is expected that future applications of vortex tube units will be concentrated where performance improvements over Joule-Thomson units, at low capital cost, are required.