Journal articles: 'Coiled tubes'

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Akgul, Dogan, Safak Metin Kirkar, Busra Selenay Onal, Ali Celen, Ahmet Selim Dalkilic, and Somchai Wongwises. "Single-phase flow heat transfer characteristics in helically coiled tube heat exchangers." Kerntechnik 87, no. 1 (February 1, 2022): 1–25. http://dx.doi.org/10.1515/kern-2021-1005.

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Abstract The aim of this review is to present a summary of the published papers of the heat transfer and pressure drop characteristics for single-phase flow in helically coiled tubes. The effect of geometrical parameters such as curvature ratio, coil pitch and working conditions such as Reynolds number, Dean number, flow rate and flow arrangement on heat transfer and pressure drop in helically coiled tubes are determined in the light of the experimental, numerical and analytical studies in the literature. Also, the effect of using nanofluids in comparison with conventional fluids, using enhanced surfaces such as corrugated, micro-finned, dimpled with regards to smooth surfaces and wire coil insert usage in helically coiled tubes are discussed. The correlations proposed for determination of Nusselt number and friction factor in helically coiled tubes are presented in detail separately under laminar and turbulent flow regimes. The studies show that usage of helically coiled tube merely gives higher heat transfer rate and pressure drop in comparison to straight one, additionally, the heat transfer performance increases with the inclusion of the combination of other passive heat transfer enhancement methods to helically coiled tube. Moreover, the subject of single-phase flow in helically coiled tubes is ascertained to be worth researching due to the fact that there are limited number of studies and is still no empirical or analytical model/correlation in the case of using enhanced surfaces and wire coil insert. Forthcoming researches on this issue in the near future will be considered as pioneer ones in literature.

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Abdul- Kareem R. Abed, Hassan Jawdat Fadhiel, Gaydaa Mahsun, and Thabet C. Yassen. "Experimental Study on The Effect of Capillary Tube Geometry on The Performance of Vapour Compression Refrigeration System." Diyala Journal of Engineering Sciences 7, no. 2 (June 1, 2014): 47–60. http://dx.doi.org/10.24237/djes.2014.07204.

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A domestic refrigerator of 5 ft3 capacity is used to study the effect of coiled diameter and pitch distance of a capillary tube. Five capillary tubes of 2 mm in diameter and 1500 mm length each are used, as same as original capillary tube of the refrigerator. The capillary tubes is formed in five shapes, each one has different coil diameter (D) namely 25, 50, 75, 100 and 125 mm in diameter, in addition three distances between each coil (pitch (P)) is tested, namely 6, 8 and 10 mm. The pressure at inlet and outlet of capillary are measured to calculate the cycle COP, as well as the power consumed by the cycle compressor is measured to calculate the mass flow rate of refrigerant. The work show that the coiled diameter of capillary tube affect the cycle COP strongly, as the capillary coiled diameter (D) increases from 25 to 100 mm the cycle COP increases from 2.8 to 3.7 when the cabinet temperature equals to 8oC. The increases of coiled diameter more than 100 mm shows insignificant effect on the cycle COP. While the pitch space of capillary tube coiled shows minor effect on the cycle COP. Moreover, to the mass flow rate of refrigerant increases with approximately ranges from 1.2−2.7

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INOUE, NORIHIRO, SHINITSU IKU, and KAZUHIDE WATANABE. "PRESSURE DROP AND HEAT TRANSFER INSIDE THE COILED FLOW CHANNEL OF SMOOTH TUBES AND INTERNALLY HELICAL-GROOVED TUBES." International Journal of Air-Conditioning and Refrigeration 20, no. 04 (December 2012): 1250023. http://dx.doi.org/10.1142/s201013251250023x.

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In this study, we investigated ways of improving the performance of heat exchangers, which are the heat pumps for use in hot-water supply systems on the hot-water supply side. Therefore, we verified experimentally the pressure drop and the heat transfer characteristics within the coiled flow channel. Five smooth copper tubes and five internally helical-grooved copper tubes with an outside diameter of 12.7 mm and coil diameters of 100 mm, 120 mm, 140 mm, 160 mm and 180 mm were used as the heat-transfer coiled tubes in the experiments. Experiments were conducted under conditions of constant isothermal heating and fluid flow inside coiled tubes with an inlet temperature of 20°C, and the flow rates of the fluid flow inside the coiled tubes were adjusted and varied to change the Reynolds number within the range of 900 to 25,000. Based on the experimental values, we proposed prediction equations to systematically calculate the friction factor and the heat transfer coefficient for different curvature radius ratios.

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Dey, Anshumaan, and Monisha M. Mandal. "Hydrodynamics Study of Oil–Water Flow in Coiled Flow Inverter." Advanced Science, Engineering and Medicine 12, no. 2 (February 1, 2020): 173–80. http://dx.doi.org/10.1166/asem.2020.2485.

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The present numerical study is an effort to examine the hydrodynamics characteristics of two immiscible liquids (oil and water) flowing in different tubes. i.e., straight, coiled and Coiled Flow Inverter (CFI) tube of equal dimensions. CFI is a novel device in which fluid flow inversion takes place at uniform interval length of tube. The effect of oil-water viscosity ratio (µoil/µwater = 1.6 and 30) on velocity contours, phase distribution and pressure drop in the different tubes were investigated. The present work show that flow pattern of oil–water flows was changed from stratified to annular flows at higher water volume fraction for µoil/µwater = 1.6 in CFI. Phase inversion of oil–water flow was observed in CFI at higher viscosity ratio (µoil/µwater = 30). There was remarkable reduction in pressure drop with the increment in volume fraction of water flowing in coiled as well as CFI. CFI being more compact can be efficiently used in industries as chemical reactor, heat exchanger, mixer, etc.

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Akeedy, Adnan Rasheed, Hajar Alias, and Sami D. Salman. "HEAT TRANSFER ENHANCEMENT USING PASSIVE TECHNIQUE: REVIEW." Jurnal Teknologi 83, no. 2 (February 28, 2021): 151–62. http://dx.doi.org/10.11113/jurnalteknologi.v83.14546.

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Preserving and saving energy have never been more important, thus the requirement for more effective and efficient heat exchangers has never been more important. However, in order to pave the way for the proposal of a truly efficient technique, there is a need to understand the shortcomings and strengths of various aspects of heat transfer techniques. This review aims to systematically identify these characteristics two of the most popular passive heat transfer techniques: nanofluids and helically coiled tubes. The review indicated that nanoparticles improve thermal conductivity of base fluid and that the nanoparticle size, as well as the concentrations of the nanoparticles plays a major role in the effectiveness of the nanofluids. Regarding the helically coiled tubes, it was discovered that the use of a coiled tube produces secondary flows, which ultimately improves the heat transfer enhancement. The third part of the review focused on microchannels and microtubes. This is mainly due to the growing need and requirement of smaller and more compact thermal cooling systems. Thus, ultimately the result of the review indicates that a combination of all these three techniques can lead to a compact and minimized heat exchanger that uses the benefits obtained from both nanofluids and helically coiled tubes in order to improve the heat transfer rate of the thermal systems.

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Gao, Weikai, Xiaoyang Xie, Xiaowei Li, and Xinxin Wu. "Influence of Coiling Direction of Helical Tube Bundles on the Thermal-Hydraulics of the HTGR Steam Generator." Journal of Physics: Conference Series 2048, no. 1 (October 1, 2021): 012032. http://dx.doi.org/10.1088/1742-6596/2048/1/012032.

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Abstract Helical tube bundles were usually adopted in the steam generators (SGs) or intermediate heat exchangers (IHXs) of high temperature gas-cooled reactors (HTGRs). Heat transfer tubes in neighboring tube layers can be coiled in the same direction or in the opposite direction. The coiling direction has influences on the thermal-hydraulic performances of the SGs or IHXs. The cross flow convection over helical tube bundles with neighboring tube layers having the same coiled direction and opposite coiled direction were numerically investigated. Reynolds stress model with standard wall functions was used for the turbulence modeling. For a helical tube bundle with neighboring layers coiled in the same direction (parallel tube layers), the tangential velocity along the coiled circumferential direction could be observed obviously. For a helical tube bundle with neighboring layers coiled in the opposite direction (crossed tube layers), there is no average tangential velocity of the whole flow filed. And the streamlines of the fluid are very complex. The flow resistances and heat transfer coefficients over helical tube bundle with parallel tube layers and crossed tube layers were compared. Although the heat transfer over helical tube bundles with crossed tube layers was 9.39% smaller than that with parallel tube layers, the pressure drop over tube bundle with crossed tube layers was much smaller compared with those with parallel tube layers.

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Garimella, S., D. E. Richards, and R. N. Christensen. "Experimental Investigation of Heat Transfer in Coiled Annular Ducts." Journal of Heat Transfer 110, no. 2 (May 1, 1988): 329–36. http://dx.doi.org/10.1115/1.3250488.

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Forced convection heat transfer in coiled annular ducts was investigated experimentally. Average heat transfer coefficients were obtained for both laminar and transition flows. Two coiling diameters and two annulus radius ratios were used in the study. The data were correlated with Dean number and Reynolds number separately and compared with the available studies of coiled circular tubes and straight annular ducts. It was found that coiling augments the heat transfer coefficients above the values for a straight annulus especially in the laminar region. However, the augmentation is less than would be expected for a coiled circular tube. The augmentation decreases as the flow enters the transition region.

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Haryoko, Luthfi A. F., Jundika C. Kurnia, and Agus P. Sasmito. "Numerical Investigation of Subcooled Boiling Heat Transfer in Helically-Coiled Tube." International Journal of Automotive and Mechanical Engineering 17, no. 1 (March 30, 2020): 7675–86. http://dx.doi.org/10.15282/ijame.17.1.2020.15.0570.

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Subcooled boiling heat transfer in helically-coiled tubes offers better heat transfer performance than any other types of boiling processes due to its ability to capture high heat flux with a relatively low wall superheat. This study investigates turbulent subcooled forced convection boiling performances of water-vapour in a helically-coiled tube with various operating conditions i.e. operating pressure, heat, and mass flux. Developed CFD model is validated against previously published experimental results using the RPI model. The model is developed based on the Eulerian-Eulerian framework coupled with k-ε RNG turbulence model and Standard Wall-Function. A good agreement is found between numerical prediction and experimental counterpart for the bulk fluid temperature and non-dimensional length. The result indicates that the subcooled boiling heat transfer in a helically-coiled tube tends to improve heat transfer coefficient and pressure drop in the domain. Subcooled boiling starts at the inner side of the helically-coiled tube (f=9900) due to the existence of secondary flow that comes from the coil curvature. Heat transfer coefficient and pressure drop increased with increasing heat flux and decreasing mass flux, and operating pressure. This is caused by the bubble movement and convective heat transfer phenomena in a helically-coiled tube. Finally, this study can provide a guideline for future research of the subcooled boiling in a helically-coiled tube.

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Mishani, Siamak, Brian Evans, Vamegh Rasouli, Reem Roufail, Soren Soe, and Peter Jaensch. "Interlaminar modelling to predict composite coiled tube failure." APPEA Journal 55, no. 1 (2015): 361. http://dx.doi.org/10.1071/aj14029.

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In a field operation that uses coiled tubing in its applications, fibre-reinforced polymer matrix composite tubing is seldom used. Fibre-composite coiled tubes offer advantages, compared to steel material, through a reduction in weight and improvement in fatigue life. The stiffness of composite material degrades progressively when increasing the number of cyclic loading. The fatigue damage and failure criteria of fibre-reinforced composite coiled tubes are more complex than that of steel; hence, failure predictions are somewhat unreliable. Among the defects in composite materials, interlaminar delamination is the foremost problem in fibre-reinforced composite material, and it leads to a reduction in strength and stiffness especially in cyclic-load conditions. Delamination causes a redistribution of the load path along the composite structure, which is unpredictable; therefore, delamination in a composite coiled tube in an oil and gas field eventually leads to final failure, which could be catastrophic. A-ply-by-ply mathematical modelling and numerical simulation method was developed to predict interlaminar delamination of filament-wound composite coiled tubes under a combination of different loading scenarios with consideration to low-cycle fatigue. The objective of this paper is to explain interlaminar delamination as an initial crack and source of stress concentration in composite coiled tubes in the framework of meso-cracking progression of matrix damage modelling of composite laminates. The paper focuses on delamination failure because the largest span of the composite lifecycle is at the crack propagation phase, which manifests itself in the form of delamination. The analysis shows that the crack front tip is not uniform, and also shows that carbon fibre possesses higher stiffness values compared to glass fibre. The paper confirms that 2D modelling cannot express the real release strain energy rate at the crack front tip. Mode-I testing, however, showed that the double cantilever beam (DCB) only represents the normal stress from the release strain energy rate. The results also indicated that there were other sources contributing to the strain energy release rate, such as inter-layer frictions and normal stress in the end notched flexure (ENF) testing mode.

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Quinlan, R. A., and M. Stewart. "Crystalline tubes of myosin subfragment-2 showing the coiled-coil and molecular interaction geometry." Journal of Cell Biology 105, no. 1 (July 1, 1987): 403–15. http://dx.doi.org/10.1083/jcb.105.1.403.

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We have produced crystalline tubes of chicken breast myosin long subfragment-2 that show order to resolutions better than 2 nm. The tubes were formed from a thin sheet in which the myosin long subfragment-2 molecules were arranged on an approximately rectangular crystalline lattice with a = 14.1 +/- 0.2 nm and b = 3.9 +/- 0.1 nm in projection. Shadowing indicated that the tube wall was approximately 7 nm thick and that the sheets from which it was formed followed a right-handed helix. Superposition of the lattices from the top and bottom of the tube produced a moire pattern in negatively stained material, but images of single sheets were easily obtained by computer image processing. Although several molecules were superimposed perpendicular to the plane of the sheet, the modulation in density due to the coiled-coil envelope was clear, indicating that the coiled-coils in these molecules were in register (or staggered by an even number of quarter pitches). In projection the coiled-coil had an apparent pitch of 14.1 nm (the axial repeat of the unit cell), but the small number of molecules (probably four) superimposed perpendicular to the plane of the sheet meant that pitches within approximately 1 nm of this value could have shown a modulation. Therefore, a more precise determination of the coiled-coil pitch must await determination of the sheet's three-dimensional structure. The coiled-coils of adjacent molecules within the plane of the sheet were staggered by an odd number of quarter pitches. This arrangement was similar to that between paramyosin molecules in molluscan thick filaments and may have features in common with other coiled-coil protein assemblies, such as intermediate filaments. Each molecule in the crystal had two types of neighbor: one staggered by an odd number of quarter pitches and the other by an even number of quarter pitches, as has been proposed for the general packing of coiled-coils (Longley, W., 1975, J. Mol. Biol., 93:111-115). We propose a model for the detailed packing within the sheet whereby molecules are inclined slightly to the plane of the sheet so that its thickness is determined by the molecular length.

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Gordon, PA, JM Norton, JM Guerra, and ST Perdue. "Positioning of chest tubes: effects on pressure and drainage." American Journal of Critical Care 6, no. 1 (January 1, 1997): 33–38. http://dx.doi.org/10.4037/ajcc1997.6.1.33.

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BACKGROUND: Maintaining a chest drainage tube in a position that is free of dependent loops, as is commonly recommended, can be very difficult. Is there a beneficial effect on the patient's outcome when the drainage tubing is free of dependent loops? OBJECTIVE: The purpose of this study was to determine, under controlled laboratory conditions, (1) what are the differences in drainage with tubing in straight, coiled, or dependent-loop (with and without periodic lifting) positions and (2) what are the differences in pressure with each of the four tubing conditions? METHODS: In laboratory simulations, pressure and drainage were observed in a chest tube drainage system that was connected to a glass bottle simulating the lung. Pressure and drainage were measured for 1 hour with the drainage tubing placed in straight, coiled, and dependent-loop positions. For the periodic lifting condition, the dependent loop was lifted and drained every 15 minutes. RESULTS: We found no differences in pressure or drainage between straight and coiled positions of the drainage tubing. However, with the dependent-loop position, pressure at the "lung" side increased from about -18 cm H2O to as high as +8 cm H2O. Drainage dropped to zero without tube lifting. When the tube was lifted and drained every 15 minutes, there was no difference in drainage with the tubing in the straight or coiled positions. CONCLUSION: Findings support recommendations to maintain tubing free of dependent loops by placing tubing in straight or coiled positions. Frequently lifting and draining a dependent loop will provide the same total drainage amount as maintaining the tubing in a straight or coiled position, but pressures may be altered sufficiently within the tube to exceed recommended levels.

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Grabezhnaya, V., A. Mikheyev, A. Alekhin, A. Kryukov, and A. Tikhomirov. "EXPERIMENTAL JUSTIFICATION OF DESIGN CHARACTERISTICS OF STEAM GENERATOR RP BREST-OD-300." PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. SERIES: NUCLEAR AND REACTOR CONSTANTS 2021, no. 2 (June 26, 2021): 218–35. http://dx.doi.org/10.55176/2414-1038-2021-2-218-235.

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The project BREST-OD-300 reactor plant (RP) with a fast neutron reactor and a lead coolant in the primary circuit is being developed in NIKIET JSC. As a steam generator (SG), a helical-type steam generator with coiled tubes with subcritical pressure water in the second circuit is considered. To substantiate the design characteristics of the secondary coolant at the State Research Center of the Russian Federation - IPPE, thermohydraulic tests of various SG models were carried out at the SPRUT stand Initially, tests were carried out on a model of a coiled steam generator consisting of two three-tube modules with a longitudinal lead flow around a three-tube bundle of coiled tubes. The influence of operating parameters on thermohydraulic characteristics and hydrodynamic stability is shown in the case of operation of one module, as well as in the joint operation of two models in the investigated range of operating parameters. At the second stage, tests of a standard steam generator model were carried out with lead flowing around 18 heat exchange tubes. In the multitube model, the downward movement of the heating coolant took place with the flow around the bundle of heat transfer tubes close to the transverse flow. Data were obtained on the hydrodynamic stability of steam generating tubes and the entire model as a whole when operating in the entire range of changes in operating parameters, which are necessary for creating a databank and further verification of calculation codes describing the ongoing thermohydraulic processes. During the tests in both models of the steam generator, there were no noises inherent in unstable operating modes of the circuit. No pulsations of water and steam temperature were found, respectively, in the inlet and outlet collectors. At high lead temperatures, the temperature of the superheated steam was always close to the lead inlet temperature. A series of works devoted to the study of heat transfer from the side of a lead coolant with a transverse flow around a package of heat exchange tubes in normal heat transfer modes and with freezing of lead has been completed. Studies have been carried out on the effect of oxygen concentration in lead on heat transfer.

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Higueras-Ruiz, Diego R., Michael W. Shafer, and Heidi P. Feigenbaum. "Cavatappi artificial muscles from drawing, twisting, and coiling polymer tubes." Science Robotics 6, no. 53 (April 21, 2021): eabd5383. http://dx.doi.org/10.1126/scirobotics.abd5383.

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Compliant, biomimetic actuation technologies that are both efficient and powerful are necessary for robotic systems that may one day interact, augment, and potentially integrate with humans. To this end, we introduce a fluid-driven muscle-like actuator fabricated from inexpensive polymer tubes. The actuation results from a specific processing of the tubes. First, the tubes are drawn, which enhances the anisotropy in their microstructure. Then, the tubes are twisted, and these twisted tubes can be used as a torsional actuator. Last, the twisted tubes are helically coiled into linear actuators. We call these linear actuators cavatappi artificial muscles based on their resemblance to the Italian pasta. After drawing and twisting, hydraulic or pneumatic pressure applied inside the tube results in localized untwisting of the helical microstructure. This untwisting manifests as a contraction of the helical pitch for the coiled configuration. Given the hydraulic or pneumatic activation source, these devices have the potential to substantially outperform similar thermally activated actuation technologies regarding actuation bandwidth, efficiency, modeling and controllability, and practical implementation. In this work, we show that cavatappi contracts more than 50% of its initial length and exhibits mechanical contractile efficiencies near 45%. We also demonstrate that cavatappi artificial muscles can exhibit a maximum specific work and power of 0.38 kilojoules per kilogram and 1.42 kilowatts per kilogram, respectively. Continued development of this technology will likely lead to even higher performance in the future.

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Grabezhnaya, V., and A. Mikheyev. "EXPERIMENTAL STUDY OF THERMAL HYDRAULICS ON THE MODEL OF HELICAL COILED STEAM GENERATOR HEATED BY LIQUID LEAD WITH LONGITUDINAL AND TRANSVERSE FLOW." PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. SERIES: NUCLEAR AND REACTOR CONSTANTS 2019, no. 1 (March 26, 2019): 132–51. http://dx.doi.org/10.55176/2414-1038-2019-1-132-151.

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The study of heat transfer in spiral coiled tubes is of great interest in view of the widespread use of such channels in engineering practice, in particular, in nuclear power engineering in the form of steam generators at research reactors and nuclear power plants. In the projected BREST-OD-300 reactor facility (RF), a configuration of helical coiled tubes is considered as a steam generator. Thermal hydraulic tests of the model steam generator RF BREST-OD-300 (version 2000) with helical coiled tubes with longitudinal coolant flow were carried out in SSC RF - IPPE at the SPRUT facility in 2011-2013 years. The test program was aimed to study heat transfer and thermal hydraulic stability of the steam generating tubes. Throughout the range of variation the regime parameters, regimes with a reversal circulation in the water loop have not been detected. Despite the fact that the results of conducted tests on the steam generator model gave extensive information on heat transfer in different zones of the steam generating tube, however, the insufficient number of heat transfer tubes in the module (only three) does not allow to conclude that the full hydrodynamic stability of BREST RF steam generator in all possible modes of operational parameters. On the other hand, in a real construction the motion of the heating coolant is omitted with flow around the bundle of tubes close to the transverse flow. Therefore, insufficient reasoning for the transferring results obtained on a three-tube model to a full-scale steam generator served as the basis for testing of a multi-tube full-height fragment model of a reduced diameter one row of the tube bundle actual steam generator. During the tests, there were no noises typical of the unstable operation of water loop. There were no oscillations of water and steam temperature, respectively, at the inlet to the collectors and out of the collectors. At high lead temperatures, the temperature of the superheated steam was always close to the inlet temperature of the lead. The tests showed the absence of the thermohydraulic instability, as in the case of longitudinal and transverse coolant flows in the investigated modes of lead and water parameters. Other parameters being equal, the steam temperature at the outlet of the steam generating tube in case of transverse flow was higher than in the case of longitudinal flow. The experimental data obtained during the testing are primarily necessary for the verification of codes that allow the correct calculation of the various operating modes of the BREST-OD-300 steam generator.

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Rasti, Mehdi, and Ji Hwan Jeong. "Assessment of Dimensionless Correlations for Prediction of Refrigerant Mass Flow Rate Through Capillary Tubes — A Review." International Journal of Air-Conditioning and Refrigeration 25, no. 04 (December 2017): 1730004. http://dx.doi.org/10.1142/s201013251730004x.

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Capillary tubes are widely used as expansion devices in small-capacity refrigeration systems. Since the refrigerant flow through the capillary tubes is complex, many researchers presented empirical dimensionless correlations to predict the refrigerant mass flow rate. A comprehensive review of the dimensionless correlations for the prediction of refrigerants mass flow rate through straight and coiled capillary tubes depending on their geometry and adiabatic or diabatic capillary tubes depending on the flow configurations has been discussed. A comprehensive review shows that most of previous dimensionless correlations have problems such as discontinuity at the saturated lines or ability to predict the refrigerant mass flow rate only for the capillary tube subcooled inlet condition. The correlations suggested by Rasti et al. and Rasti and Jeong appeared to be general and continuous and these correlations can be used to predict the refrigerant mass flow rate through all the types of capillary tubes with wide range of capillary tube inlet conditions including subcooled liquid, two-phase mixture, and superheated vapor conditions.

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Vinn, Olev. "Tube ultrastructure of the fossil genus Rotularia Defrance, 1827 (Polychaeta, Serpulidae)." Journal of Paleontology 82, no. 1 (January 2008): 206–12. http://dx.doi.org/10.1666/06-125.1.

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Among Polychaete annelids, calcareous tubes occur in Serpulidae, Spirorbidae, Sabellidae, and Cirratulidae (Perkins, 1991; Fischer et al., 2000). The tubes of most serpulids are completely or partially cemented to the substrate. The fossil genus Rotularia has a peculiar unattached, spirally coiled tube, thus well distinguishable from the other known serpulids. Tube records of Rotularia are known from Mesozoic (Late Jurassic) (Ball, 1960; Stevens, 1967) to Early Tertiary sediments, becoming very common during the Cretaceous and Eocene (see Savazzi, 1995). It also has a global distribution (Wrigley, 1951; Ball, 1960; Keen, 1961; Regenhardt, 1961; Howell, 1962; Stevens, 1967; Chiplonkar and Tapaswi, 1973; Ware, 1975; Lommerzheim, 1979; Macellari, 1984; Jäger, 1993).

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Djordjevic, Milan, Velimir Stefanovic, Dragan Kalaba, Marko Mancic, and Marko Katinic. "Radiant absorption characteristics of corrugated curved tubes." Thermal Science 21, no. 6 Part B (2017): 2897–906. http://dx.doi.org/10.2298/tsci160420263d.

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The utilization of modern paraboloidal concentrators for conversion of solar radiation into heat energy requires the development and implementation of compact and efficient heat absorbers. Accurate estimation of geometry influence on absorption characteristics of receiver tubes is an important step in this process. This paper deals with absorption characteristics of heat absorber made of spirally coiled tubes with transverse circular corrugations. Detailed 3-D surface-to-surface Hemicube method was applied to compare radiation performances of corrugated and smooth curved tubes. The numerical results were obtained by varying the tube curvature ratio and incident radiant heat flux intensity. The details of absorption efficiency of corrugated tubes and the effect of curvature on absorption properties for both corrugated and smooth tubes were presented. The results may have significance to further analysis of highly efficient heat absorbers exposed to concentrated radiant heating.

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Li, Zhaoxu, Shengyao Jiang, Xingtuan Yang, Yichuan Huang, Guangyu Zhu, Jiyuan Tu, and Hongye Zhu. "Bubbly-intermittent flow transition in helically coiled tubes." Chemical Engineering Journal 323 (September 2017): 96–104. http://dx.doi.org/10.1016/j.cej.2017.04.029.

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Prabhanjan, Devanahalli G., Timothy J. Rennie, and G. S. Vijaya Raghavan. "Natural convection heat transfer from helical coiled tubes." International Journal of Thermal Sciences 43, no. 4 (April 2004): 359–65. http://dx.doi.org/10.1016/j.ijthermalsci.2003.08.005.

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Sharma, Loveleen, K. D. P. Nigam, and Shantanu Roy. "Single phase mixing in coiled tubes and coiled flow inverters in different flow regimes." Chemical Engineering Science 160 (March 2017): 227–35. http://dx.doi.org/10.1016/j.ces.2016.11.034.

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Bozzoli, Fabio, Luca Cattani, Sara Rainieri, Fermín S. V. Bazán, and Leonardo S. Borges. "Estimation of the local heat transfer coefficient in coiled tubes." International Journal of Numerical Methods for Heat & Fluid Flow 27, no. 3 (March 6, 2017): 575–86. http://dx.doi.org/10.1108/hff-03-2016-0097.

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Purpose Most of the passive techniques for enhancing heat transfer inside pipes (e.g. rough surfaces, swirl-flow devices and coiled tubes) give origin to an irregular distribution of the heat transfer coefficient at the fluid–wall interface along the wall perimeter. This irregular distribution could be critical in some industrial applications, but most of the available research papers, mainly due to the practical difficulty of local measuring heat flux on the internal wall surface of a pipe, present the results only in terms of Nusselt number averaged along the wall circumference. This paper aims to study the application of inverse problem solution techniques, which could overcome this limitation. Design/methodology/approach With regard to the estimation of the local convective heat transfer coefficient in coiled tubes, two different inverse heat conduction problem solution techniques were considered and compared both by synthetic and experimental data. Findings The paper shows the success of two inverse problem solution techniques in the estimation of the local convective heat transfer coefficient in coiled tubes. Originality/value This paper fulfills an identified need because most of the available research papers present the results only in terms of average thermal performance, neglecting local behavior.

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Elshamy, Samir M., Mohamed T. Abdelghany, M. R. Salem, and O. E. Abdellatif. "Energy and Exergy Analysis of Shell and Coil Heat Exchanger Using Water Based Al2O3 Nanofluid Including Diverse Coil Geometries: An Experimental Study." Journal of Nanofluids 9, no. 1 (March 1, 2020): 13–23. http://dx.doi.org/10.1166/jon.2020.1727.

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The aim of this research is to investigate experimentally the characteristics of the convective heat transfer and exergy analysis of pure water and water based Al2O3 nanofluid through helical coiled tubes (HCTs) and conical coiled tubes (CCTs) inside shell and coil heat exchangers. HCT and CCT fabricated with different coil torsions (λ) ranges from 0.0202 to 0.052 with different two angles (0° and 45°) while have the same curvature ratio (δ = 0.0564). The effects of mean coil torsion, the cone angle and nanoparticles volume concentration on the thermal performance were investigated. Results indicated that the overall heat transfer coefficient (Uov), convection heat transfer coefficient (ht), the tube side Nusselt number (Nut), effectiveness (ɛ) and exergy efficiency (ηex) of nanofluids are higher than those of the pure water at same flow condition, and this increase goes up with the increase in particle volume concentration (ϕ). The results also showed that Uov, ht, Nut, ɛ and ηex increases by decreasing the coil torsion from 0.052 to 0.0202. Correlations for Nut as a function of the investigated parameters are obtained.

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Blackbourn, H. D., and A. P. Jackson. "Plant clathrin heavy chain: sequence analysis and restricted localisation in growing pollen tubes." Journal of Cell Science 109, no. 4 (April 1, 1996): 777–86. http://dx.doi.org/10.1242/jcs.109.4.777.

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Clathrin-coated vesicles were isolated from soybean (Glycine max L.) cells in suspension culture and their purity was assessed using SDS-PAGE, peptide sequencing and electron microscopy. Antibodies raised to these coated vesicles were used to immunoscreen a soybean cDNA library in lambda gt11 and isolate a partial clone of the clathrin heavy chain (HC) gene. Full-length cDNA for soybean clathrin HC was deduced by 5′ and 3′ cDNA amplification. The cDNA encodes an amino acid sequence of 1,700 residues, which is slightly larger than rat clathrin HC and may account for the reduced mobility of plant clathrin on SDS-PAGE. Insertion of these extra residues is largely confined to the amino and carboxy termini. Other domains within the heavy chain arms, including those implicated in light chain binding and trimerisation, are relatively well conserved between eukaryotes. A computer algorithm to determine alpha-helical coiled-coil structures reveals that only one domain, aligning to residues 1,460-1,489 in rat clathrin HC, has a high probability for coiled-coil structure in all five eukaryotic clathrin HC sequences. This provides further evidence that the interaction between clathrin heavy and light chains is mediated by three bundles of coiled-coils near to the carboxy terminus. In analysing the role of plant clathrin in endocytotic trafficking, as against trafficking from the Golgi apparatus to the vacuole, our attention was focused on membrane recycling in tip-growing pollen tubes. These rapidly growing cells are highly secretory and require a high level of plasma membrane recycling to maintain the tube tip architecture. Monoclonal antibodies to plant clathrin HC confirmed that coated vesicles are relatively abundant in tip-growing pollen tubes of Lilium longiflorum. This analysis also demonstrated that a high proportion of the clathrin present is in an assembled state, suggesting a highly dynamic trafficking pathway. Immunofluorescence analysis of pollen tubes revealed that clathrin localises to the plasma membrane at the apex of the pollen tube tip, which is consistent with high levels of clathrin-mediated membrane recycling. The use of these reagents in conjunction with tip-growing pollen tubes has created a unique opportunity to examine the basis for constitutive endocytosis, so that the more complex question of receptor-mediated pathways in plants can also be assessed.

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Hewitt, G. F., and S. Jayanti. "Prediction of film inversion in two-phase flow in coiled tubes." Journal of Fluid Mechanics 236 (March 1992): 497–511. http://dx.doi.org/10.1017/s0022112092001502.

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Depending on the flow conditions, the liquid film in annular two-phase flow in coiled tubes may be pushed towards the outer or the inner side by the centrifugal force. It is important to understand the mechanism of this ‘film inversion’ in order to develop a predictive model for the film thickness distribution. In this paper, this phenomenon is studied analytically, and a new criterion, based on the secondary flow in the thin liquid film, is proposed to predict its occurrence. The criterion shows good agreement with available experimental data. It is suggested that the analytical model can readily be extended to predict the distribution of the film thickness and film flow rate in coiled tubes.

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He, Jinjing, Jingwen Gong, Qingqing Zheng, and Jin Jiang. "Repositioning of the Severe Prolapsed Silicone Tubes after Bicanalicular Nasal Intubation: A Novel Technique." Journal of Ophthalmology 2021 (March 6, 2021): 1–6. http://dx.doi.org/10.1155/2021/6669717.

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Background. Bicanalicular nasal intubation is widely used in lacrimal drainage system surgery. Its common complication is lateral displacement or spontaneous prolapse. When the distal part of the silicone tubes cannot be seen in the nose endoscopically, either repositioning or removal could be a challenge. We developed a simple technique to reposition the severe prolapsed silicone tubes. Method. This retrospective study included 6 patients with severe prolapsed silicone tubes who had undergone bicanalicular nasal intubation between January 2017 and December 2019. We used a memory wire probe to pull a nylon suture through the lacrimal passage retrograde. Then, the nylon suture was cut into two lines. One line was coiled to the prolapsed tube and tied to another line. This nylon turned into a “lasso” to capture the silicone tube and then lock its knot. By pulling the nylon suture, the severe prolapsed silicone tube was repositioned to the nasal cavity. Results. Using this technique, we successfully repositioned severe prolapsed silicone tubes without any complication in 6 cases. Conclusions. Silicone tube reposition guiding by using a memory wire probe is an optional technique in the treatment of prolapse of silicone tubes, particularly if the distal part of the silicon tube was embedded in the lacrimal sac and cannot be seen in the nose by endoscopy. It is a feasible, minimally invasive, safe, and effective method, avoiding premature tube removal.

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Grabezhnaya, V., A. Mikheyev, and A. Kryukov. "ON THE EFFECT OF OXYGEN IMPURITIES ON HEAT TRANSFER AT TRANSVERSAL FLOW OF STEAM-GENERATING TUBES IN NORMAL HEAT TRANSFER MODES AND WITH LEAD FREEZE." PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. SERIES: NUCLEAR AND REACTOR CONSTANTS 2020, no. 3 (September 26, 2020): 135–47. http://dx.doi.org/10.55176/2414-1038-2020-3-135-147.

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The BREST-OD-300 steam generator project being developed at NIKIET is pioneering both in terms of the heat carrier used (lead) and in design implementation (coils of helical heat transfer tubes). The advantages of the designs of steam generators made in the form of helical coiled tubes, in comparison with straight tube designs are obvious. Helical coiled tubes are used in heat exchange equipment not only to increase the heat transfer surface, to solve the problem of thermal expansion, but also to increase the coefficient of heat transfer to the fluid flowing inside the tubes. In 2011-2017 years the thermohydraulic tests of various models of lead-heated steam generator were carried out at the IPPE SPRUT facility (IPPE). The test program was aimed to study the heat transfer and the thermal-hydraulic stability of the steam generating tubes. Throughout the entire range of changes in operating parameters, no pulsating modes were detected with overturn of circulation in the water circuit. The design temperatures of superheated steam were obtained in nominal operation. The results provide extensive information on water heat transfer in different zones of the steam generating channel under various operating conditions (nominal and partial modes, starting modes). However, to verify the computer codes, experimental data on the heat transfer of lead coolant around the bundles of heat transfer tubes are necessary. Due to the small twist angle of the tubes in a full-scale steam generator, it can be said that heat transfer is close to heat transfer during transverse flow. A model with a transverse flow of lead coolant around steam-generating tubes was developed at the SSC RF - IPPE. The main goal of the research was to obtain data on the effect of oxygen concentration in lead on heat transfer in normal heat transfer modes and with lead freezing. Throughout the entire range of changes in the initial temperature values of lead and water, blocking of the annular space by frozen lead was not recorded.

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Ji, Cui Lian, Ji Tian Han, Chang Nian Chen, Xia Dong, and Ling Jian Kong. "Influence of Geometry Parameters on Critical Heat Flux in Helically Coiled Tubes: Development of Correlation." Applied Mechanics and Materials 353-356 (August 2013): 3077–80. http://dx.doi.org/10.4028/www.scientific.net/amm.353-356.3077.

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Based on 2006 look-up tables to analysis the effect of pipe diameters on CHF, the correlations are established for horizontal helically coiled tube by introducing equivalent geometrical parameter. According to experimental data, it is found that the correlation is very suitable, and the regularity of horizontal helically coiled tube geometry parameters on CHF tends to be consistent with that of a vertical tube.

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Chung-Szu Wei, Yur-Tsai Lin, Chi-Ch. "A Performance Comparison Between Coiled and Straight Capillary Tubes." Heat Transfer Engineering 21, no. 2 (March 2000): 62–66. http://dx.doi.org/10.1080/014576300271031.

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29

Acharya, Narasimha, Mihir Sen, and Chang Hsueh-Chia. "Heat transfer enhancement in coiled tubes by chaotic mixing." International Journal of Heat and Mass Transfer 35, no. 10 (October 1992): 2475–89. http://dx.doi.org/10.1016/0017-9310(92)90090-f.

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30

Acharya, Narasimha, Mihir Sen, and Chang Hsueh-Chia. "Thermal entrance length and Nusselt numbers in coiled tubes." International Journal of Heat and Mass Transfer 37, no. 2 (January 1994): 336–40. http://dx.doi.org/10.1016/0017-9310(94)90105-8.

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31

Ma, Weimin, Mingyuan Zhang, and Xuejun Chen. "High-quality critical heat flux in horizontally coiled tubes." Journal of Thermal Science 4, no. 3 (September 1995): 205–11. http://dx.doi.org/10.1007/bf02650830.

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32

Hart, J., J. Ellenberger, and P. J. Hamersma. "Single- and two-phase flow through helically coiled tubes." Chemical Engineering Science 43, no. 4 (1988): 775–83. http://dx.doi.org/10.1016/0009-2509(88)80072-1.

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33

Zhou, Guobing, and Yufeng Zhang. "Inlet pressure fluctuation characteristics of coiled adiabatic capillary tubes." Applied Thermal Engineering 33-34 (February 2012): 183–89. http://dx.doi.org/10.1016/j.applthermaleng.2011.09.033.

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34

Nada, S. A., W. G. El Shaer, and A. S. Huzayyin. "Performance of multi tubes in tube helically coiled as a compact heat exchanger." Heat and Mass Transfer 51, no. 7 (December 4, 2014): 973–82. http://dx.doi.org/10.1007/s00231-014-1469-z.

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35

DABAS, J. K., SUDHIR KUMAR, A. K. DODEJA, and K. S. KASANA. "MODELING OF A HELICALLY COILED HFC134a EVAPORATOR." International Journal of Air-Conditioning and Refrigeration 22, no. 03 (September 2014): 1450016. http://dx.doi.org/10.1142/s2010132514500163.

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A computer simulation model has been developed for the performance analysis and design optimization of a helical coil and cylindrical shell type evaporator working with HFC-134a by using the appropriate empirical correlations of heat transfer coefficient and pressure drop in the helical tubes as available in the literature. This model is based on a numerical method of cell discretization of shell side and tube side of the evaporator. The local values of variables are calculated and the mass, momentum and energy balance is applied to each small cell. The whole sequential and iterative procedure to satisfy the boundary conditions has been transformed in the computer codes. The model has been validated by comparing with the actual results of an experimental study which is also a part of this work. A detailed analysis of the effects of varying input parameters of both fluids on the performance of evaporator was carried out with the help of this model. It also gives the optimum values of mass velocity of refrigerant and the helical tube diameter against the available flow conditions of refrigerant and of external fluid and the required degree of vapor superheat at the exit of evaporator. Thus it provides an easy solution in both the cases of either the performance optimization of an existing evaporator or the design optimization of a new evaporator. The inherent errors in the outcome of correlations for heat transfer, pressure drop and refrigerant properties are the limitations of this model.

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36

Elsayed, A., R. K. Al-dadah, S. Mahmoud, and A. Rezk. "Experimental and theoretical investigation of small-scale cooling system equipped with helically coiled evaporator and condenser." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 226, no. 3 (September 14, 2011): 724–37. http://dx.doi.org/10.1177/0954406211414790.

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Utilizing helically coiled tubes evaporator and condenser in cooling applications is promising due to their higher heat transfer coefficients compared to straight tube because of the effect of centripetal forces. With growing interest in miniature and efficient refrigeration systems, small helical coil diameter can offer significant advantages in terms of being compact, lightweight, and improved coefficient of performance (COP). This article describes a performance study of small-scale vapour compression cooling system (100 W cooling capacity) equipped with shell and helically coiled tube evaporator and condenser. A detailed mathematical model has been developed for this system based on thermodynamic principles and relevant heat transfer correlations. The model was validated using experimental results from a representative small size cooling system with agreement of ±5 per cent. The model was then used to carry out performance optimization in terms of the evaporator and condenser geometric parameters including helical coil diameter, tube inside diameter, and surface area ratio. For the range of geometrical parameters investigated, the model predicts that as the coil diameter decreases, the Cooling COP improves.

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KAEW-ON, JATUPORN, SAKARIN CHINGULPITAK, and SOMCHAI WONGWISES. "EXPERIMENTAL INVESTIGATION OF R134a FLOWING THROUGH ADIABATIC HELICALLY COILED CAPILLARY TUBES." International Journal of Air-Conditioning and Refrigeration 20, no. 01 (March 2012): 1250001. http://dx.doi.org/10.1142/s2010132512500010.

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The effects of the relevant parameters on the flow characteristic of R134a flowing through adiabatic helical capillary tubes were experimentally studied. The capillary tubes' diameter, coil diameter, and parameters relating to flow conditions such as inlet pressures and degree of subcooling were the major parameters investigated. The test section was made from copper tubing with inner diameters of 1.07, 1.27, and 1.62 mm. The coil diameters were 25, 50, and 100 mm. The local pressure and temperature distributions along the length of the capillary tubes were measured at inlet pressures ranging from 10 to 14 bar, mass flow rates from 8 to 20 kg/h, and degrees of subcooling from 0.5°C to 15°C. The metastable flow and the delay of vaporization of R134a are also presented and discussed. The results showed that the capillary diameter had more of a significant effect on the mass flow rate than the other variables.

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Bhangle, Ms K. P. "CFD Analysis of the Optimization of Length of Capillary Tube for a Vapor Compression Refrigeration System." International Journal for Research in Applied Science and Engineering Technology 9, no. 8 (August 31, 2021): 2567–78. http://dx.doi.org/10.22214/ijraset.2021.37780.

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Abstract: The capillary tube is commonly employed in refrigerant flow control systems. As a result, the capillary tube's performance is optimal for good refrigerant flow. Many scholars concluded performance utilising experimental, theoretical, and analysis-based methods. This paper examines the flow analysis of a refrigerant within a capillary tube under adiabatic flow circumstances. For a given mass flow rate, the suggested model can predict flow characteristics in adiabatic capillary tubes. In the current work, R-134a refrigerant has been replaced by R600a refrigerant as a working fluid inside the capillary tube, and the capillary tube design has been modified by altering length and diameter, which were obtained from reputable literature. The analysis is carried out using the ANSYS CFX 16.2 software. The results show thatutilising a small diameter and a long length (R600a refrigerant flow) is superior to the present helical capillary tube. The most appropriate helical coiled design with a diameter of 0.8 mm and a length of 3 m is proposed. Keywords: Capillary Tube, Condenser, Refrigeration effect, CFD.

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Elamin, M. R., Babiker Y. Abdulkhair, and Kamal K. Taha. "Effect of Urea on the Shape and Structure of Carbon Nanotubes." Zeitschrift für Naturforschung A 73, no. 2 (January 26, 2018): 113–20. http://dx.doi.org/10.1515/zna-2017-0288.

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AbstractCoiled multiwall carbon nanotubes (MWCNTs) were prepared on Fe, Co, and Ni metal oxides supported on α-Al2O3 using urea as fuel and catalyst surface modifying agent by catalytic chemical vapour deposition (CCVD). The shape of the nanotubes was influenced by the addition of urea, where coiled and uncoiled tubes were obtained in the presence and absence of urea, respectively. The MWCNTs were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and nitrogen adsorption analysis. The coiling/uncoiling of the nanotubes was visualized from the SEM and TEM images of the prepared specimens. The XRD data showed the characteristic peaks of the nanotubes. BET analysis of the coiled tubes revealed 85.57 m2 g−1 surface area with a pore diameter 102.2–110.8 Å. A mechanism for the nanotubes coiling is suggested.

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Lara, Caique, Julie Villamil, Anthony Abrahao, Aparna Aravelli, Guilherme Daldegan, Sharif Sarker, Daniel Martinez, and Dwayne McDaniel. "Development of an Innovative Inspection Tool for Superheater Tubes in Fossil Fuel Power Plants." Materials Evaluation 79, no. 7 (July 1, 2021): 728–38. http://dx.doi.org/10.32548/2021.me-04212.

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Fossil fuel power plants are complex systems containing multiple components that require periodic health monitoring. Failures in these systems can lead to increased downtime for the plant, reduction of power, and significant cost for repairs. Inspections of the plant’s superheater tubes are typically manual, laborious, and extremely time-consuming. This is due to their small diameter size (between 1.3 and 7.6 cm) and the coiled structure of the tubing. In addition, the tubes are often stacked close to each other, limiting access for external inspection. This paper presents the development and testing of an electrically powered pipe crawler that can navigate inside 5 cm diameter tubes and provide an assessment of their health. The crawler utilizes peristaltic motion within the tubes via interconnected modules for gripping and extending. The modular nature of the system allows it to traverse through straight sections and multiple 90° and 180° bends. Additional modules in the system include an ultrasonic sensor for tube thickness measurements, as well as environmental sensors, a light detecting and ranging (LiDAR) sensor, and camera. These modules utilize a gear system that allows for 360° rotation and provides a means to inspect the entire internal circumference of the tubes.

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41

Williams, EG, V. Kaul, JL Rouse, and BF Palser. "Overgrowth of Pollen Tubes in Embryo Sacs of Rhododendron Following Interspecific Pollinations." Australian Journal of Botany 34, no. 4 (1986): 413. http://dx.doi.org/10.1071/bt9860413.

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Frequent overgrowths of pollen tubes within the embryo sac are characteristic of a number of interspecific crosses in the genus Rhododendron (Ericaceae). The combined techniques of sectioning, squashing and whole-ovule clearing have confirmed that in ovules showing this phenomenon the pollen tube fails to terminate growth and release sperms on entry into a synergid; instead it continues to grow beyond the synergid and egg cell, often filling the main body of the embryo sac with a coiled and distorted mass. Such ovules fail to develop further. The occurrence and possible causes of this error syndrome are discussed.

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42

Yoon, Dong-Hyeog, Ju-Yeop Park, and Kwang-Won Seul. "Numerical Study of Turbulent Heat Transfer in Helically Coiled Tubes." Transactions of the Korean Society of Mechanical Engineers B 36, no. 8 (August 1, 2012): 783–89. http://dx.doi.org/10.3795/ksme-b.2012.36.8.783.

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Kaji, Masou, Koji Mori, Shigeyasu Nakanishi, Kentaro Hirabayasi, and Masaya Ohishi. "Dryout and Wall Temperature Fluctuations in Helically Coiled Evaporating Tubes." Transactions of the Japan Society of Mechanical Engineers Series B 61, no. 585 (1995): 1811–17. http://dx.doi.org/10.1299/kikaib.61.1811.

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44

Kanatani, Kentaro, Takashi Yamamoto, Yutaka Tamaura, and Hiroshige Kikura. "A model of a solar cavity receiver with coiled tubes." Solar Energy 153 (September 2017): 249–61. http://dx.doi.org/10.1016/j.solener.2017.05.061.

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KANATANI, Kentaro, Takashi YAMAMOTO, Yutaka TAMAURA, and Hiroshige KIKURA. "A model of a solar cavity receiver with coiled tubes." Proceedings of Mechanical Engineering Congress, Japan 2017 (2017): J0540103. http://dx.doi.org/10.1299/jsmemecj.2017.j0540103.

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46

Ali, Mohamed E. "Laminar natural convection from constant heat flux helical coiled tubes." International Journal of Heat and Mass Transfer 41, no. 14 (July 1998): 2175–82. http://dx.doi.org/10.1016/s0017-9310(97)00322-0.

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47

Ali, Mohamed E. "Experimental investigation of natural convection from vertical helical coiled tubes." International Journal of Heat and Mass Transfer 37, no. 4 (March 1994): 665–71. http://dx.doi.org/10.1016/0017-9310(94)90138-4.

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48

Zhu, Guangyu, Xingtuan Yang, Shengyao Jiang, and Hongye Zhu. "Intermittent gas-liquid two-phase flow in helically coiled tubes." International Journal of Multiphase Flow 116 (July 2019): 113–24. http://dx.doi.org/10.1016/j.ijmultiphaseflow.2019.04.013.

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Redlinger-Pohn, Jakob D., Lukas A. Jagiello, Wolfgang Bauer, and Stefan Radl. "Mechanistic understanding of size-based fiber separation in coiled tubes." International Journal of Multiphase Flow 83 (July 2016): 239–53. http://dx.doi.org/10.1016/j.ijmultiphaseflow.2016.04.008.

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Bozzoli, F., L. Cattani, A. Mocerino, and S. Rainieri. "Turbulent flow regime in coiled tubes: local heat-transfer coefficient." Heat and Mass Transfer 54, no. 8 (August 8, 2017): 2371–81. http://dx.doi.org/10.1007/s00231-017-2127-z.

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Journal articles on the topic 'Coiled tubes'

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