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Simulation, Evaluation, and Optimization of Thermal Energy Systems
Published in Steven G. Penoncello, Thermal Energy Systems, 2018
6.8 A vortex tube is a device that splits a flow of air into two streams, one hot and one cold, without any moving parts. If you are not familiar with vortex tubes, read about them online. They are sometimes used in industrial applications for spot cooling. The cooling performance data for a particular vortex tube are shown in Table P6.8. This table shows the temperature difference between the incoming air flow and the cold air leaving the tube as a function of the inlet pressure of the air into the tube and the mass flow rate of the cold air stream, represented as a percent of the incoming flow. Use the exact fitting technique to develop an empirical equation that can be used to predict the temperature difference between the inlet air and the cold exit air over the range of the data provided. Estimate the accuracy of the empirical equation by developing a deviation plot that shows all of the available data.
Drilling in the Permafrost with Chilled-Air Scavenging
Published in B.B. Kudryashov, A.M. Yakovlev, Drilling in the Permafrost, 1991
B.B. Kudryashov, A.M. Yakovlev
Based on a number of tests carried out on laboratory experimental stands, several modifications of the vortex tubes, theoretical and developmental work and an efficient model of the vortex tube refrigerator PVKh-LGI-3 for underground applications were developed (Fig. 2.12b) to suit the conditions of drilling small diameter holes, especially for diamond drilling. The housing 4 of the vortex tube refrigerator, which simultaneously links the drill string and the drilling tool, is located in the protective casing 1. Compressed air from the drill string enters the scroll casing 5 through a channel in the casing 4 via a nozzle. From here it enters the vortex tube 3 at a high tangential velocity. The air is divided into cold and hot streams in the vortex tube. In the upper portion of the vortex tube 3, the vortex is dissipated by the crosspiece 2 after which the hot stream flows through slots in the casing 4 into the annular space of the drill hole while the cold stream of air passes through the diaphragm 7 and the diffuser 6 into the core drill tube 8, from where it is delivered to the bottom of the drill hole. Flowing from under the drill crown it passes through the space between the walls of the drill hole and the core drill tube and eventually mixes with the hot air stream.
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.
Computational study of temperature separation for a three-dimensional vortex tube with cold exit diameter and nozzle number variation
Published in International Journal of Ambient Energy, 2022
Ravi Kant Singh, Achintya Kumar Pramanick, Subhas Chandra Rana
The vortex tube (VT) is also known as a flow separator device. It has no moving mechanical parts. Through intake nozzles, the working fluid enters tangentially at high pressure to provide initial swirling motion. It divides the inlet fluid into two types: one that flows near the centreline and is at a low temperature, and the other that flows near the perimeter has a higher temperature than the inlet fluid. By modulating the throttle valve near the hot outlet, the mass flow rate can be adjusted. The VT is a credible device to generate expeditious spot cooling effect, cooling electronic control board, gas liquefication, used instead of coolant in the machining operation, cooling heat seals, cooling CCTV cameras, cooling machining operations, setting hot melts, cooling gas samples, cooling soldered parts, environmental chambers using inlet fluid mainly as compressed air. The advantage of a vortex tube is that it requires no chemicals or electricity.
Assessment of drilling-induced damage in CFRP under chilled air environment
Published in Materials and Manufacturing Processes, 2018
John Abish, Pratik Samal, M. S. Narenther, C. Kannan, A. S. S. Balan
In this study, a new avenue has been explored by examining the effect of chilled air on the drilling characteristics of CFRP. The chilled air was produced using a vortex cold air gun according to the principle of Ranque–Hilsch vortex tube. A range of temperatures can be obtained by varying the input pressure of the vortex tube owing to the interdependence of the two properties. Cold air at a pressure of 1 bar and temperature of 2°C were used in the present investigation. The results obtained from these machining experiments were compared to those performed under dry atmospheric air conditions. Since the objective of this work is to investigate the influence of velocity, feed rate, and working environment on drilling characteristics of CFRP, three levels of velocity and feed rate with two different environments (dry and chilled air) were considered and machining matrix were formulated. This is presented in Table 3.