Log in

Relevant bibliographies by topics / Closed tube / Journal articles

To see the other types of publications on this topic, follow the link: Closed tube.

Journal articles on the topic 'Closed tube'

Author: Grafiati

Published: 4 June 2021

Last updated: 11 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Closed tube.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Sirianni, Nicky M., Huijun Yuan, John E. Rice, Ronit S. Kaufman, John Deng, Chandler Fulton, and Lawrence J. Wangh. "Closed-Tube Barcoding." Genome 59, no. 11 (November 2016): 1049–61. http://dx.doi.org/10.1139/gen-2016-0026.

Full text

Abstract:

Here, we present a new approach for increasing the rate and lowering the cost of identifying, cataloging, and monitoring global biodiversity. These advances, which we call Closed-Tube Barcoding, are one application of a suite of proven PCR-based technologies invented in our laboratory. Closed-Tube Barcoding builds on and aims to enhance the profoundly important efforts of the International Barcode of Life initiative. Closed-Tube Barcoding promises to be particularly useful when large numbers of small or rare specimens need to be screened and characterized at an affordable price. This approach is also well suited for automation and for use in portable devices.

APA, Harvard, Vancouver, ISO, and other styles

2

Nasr, Mohamed M. "Closed-tube Thoracostomy." Surgical Laparoscopy, Endoscopy & Percutaneous Techniques 24, no. 4 (August 2014): 342–44. http://dx.doi.org/10.1097/sle.0000000000000028.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Linley, F. H. "The Impact of Tube Plugging on Closed Feedwater Heater Operation and Maintenance." Journal of Pressure Vessel Technology 109, no. 2 (May 1, 1987): 212–18. http://dx.doi.org/10.1115/1.3264898.

Full text

Abstract:

Failures of tubes in closed feedwater heaters are due to localized thermal, mechanical and chemical processes, in combination with the susceptibility of the tube material involved. Experience has demonstrated that changes in operating practice such as feedwater chemistry, frequency of exposure to atmosphere on shutdown and other factors often modify the environmental conditions and introduce unanticipated causes of tube failure. Good practice calls for immediate corrective action, whenever tubes fail, to arrest extension of the problem. Such corrective action is based on an accurate determination of the location of each failure with respect to the tube pass, position in the tube field and distance from the face of the tubesheet. Nondestructive examination and individual tube hydro test of adjacent and other suspect tubes for incipience of failure is required, including the examination of failure specimens, if they can be recovered. More than one failure mechanism may be in process in a heater and no problem potential should be treated casually. Analysis of tube plugging should consider the affect of each failure on heater performance and other equipment in the system, the probability of chronic, continuing failures and the ultimate number of tubes that can be plugged before plant capacity is curtailed. Once the tubes that should be plugged have been determined, plugging systems and installation techniques must also be addressed, with emphasis on preventing secondary damage from failed tubes and the avoidance of any failure caused by the plugs themselves.

APA, Harvard, Vancouver, ISO, and other styles

4

Rossing, Thomas. "Open and closed tube resonators." Physics Teacher 24, no. 8 (November 1986): 459. http://dx.doi.org/10.1119/1.2342087.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Kappert, Chuck. "Closed Tube with Varying Length." Physics Teacher 44, no. 9 (December 2006): 566. http://dx.doi.org/10.1119/1.2396765.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Hong, Yi-du, Bai-quan Lin, and Chuan-jie Zhu. "Premixed methane/air gas deflagration simulations in closed-end and open-end tubes." International Journal of Spray and Combustion Dynamics 8, no. 4 (June 22, 2016): 271–84. http://dx.doi.org/10.1177/1756827716648640.

Full text

Abstract:

The overpressures, flame velocities and flow speeds were investigated in closed-end and open-end tubes via numerical simulations. Our results suggest that the tube geometry influences the evolution of these parameters. The peak overpressure initially decreased and eventually increased with the aspect ratio in both types of tubes. The flow speed initially increased and then decreased with the propagation distance in the closed-end tube, but it increased with increasing distance in the open-end tube. Empirical equations relating the peak overpressure and the peak flow speed are presented. The flame velocities in the open-end tubes were always greater than those in the closed-end tubes, especially the maximum flame velocity. The open end promoted flame acceleration, while the closed end resulted in near-wall deceleration. The results provide a reference for future limited-space gas explosion studies.

APA, Harvard, Vancouver, ISO, and other styles

7

Goldshtein, A., P. Vainshtein, M. Fichman, and C. Gutfinger. "Resonance gas oscillations in closed tubes." Journal of Fluid Mechanics 322 (September 10, 1996): 147–63. http://dx.doi.org/10.1017/s0022112096002741.

Full text

Abstract:

The problem of gas motion in a tube closed at one end and driven at the other by an oscillating poston is studied theoretically. When the piston vibrates with a finite amplitude at the first acoustic resonance frequency, periodic shock waves are generated, travelling back and forth in the tube. A perturbation method, based on a small Mach number. M and a global mass conservation condition, is employed to formulate a solution of the problem in the form of two standing waves separated by a jump (shock front). By expanding the equations of motion in a series of a small parameter ε = M½, all hydrodynamic properties are predicted with an accuracy to second-order terms, i.e. to ε2. It is found that the first-order solution coincides with the previous theories of Betchov (1958) and Chester (1964), while additional terms predict a non-homogeneous time-averaged pressure along the tube. This prediction compares favourably with experimental results from the literature. The importance of the phenomenon is discussed in relation to different transport processes in resonance tubes.

APA, Harvard, Vancouver, ISO, and other styles

8

Greschik, G., and K. C. Park. "The Deployment of Curved Closed Tubes." Journal of Mechanical Design 118, no. 3 (September 1, 1996): 337–39. http://dx.doi.org/10.1115/1.2826889.

Full text

Abstract:

A critical review of previous work on the unfurling of helically curved tubes (Greschik et al, 1994, 1996) is conducted, which leads to the proposition of a continuous and smooth deployment concept akin to the Collapsible Tube Mast (Aguirre, 1985) for curved tubes. This involves the collapse of the cross section and the subsequent roll-up of its halves one upon the other onto a storage drum. The concept’s applicability to closed tubes is investigated and a method for the alleviation of the deleterious membrane strains in the stowed state is proposed.

APA, Harvard, Vancouver, ISO, and other styles

9

Amano, R. S. "A Numerical Study of Turbulent Axisymmetric Jets Flowing Into Closed Tubes." Journal of Energy Resources Technology 108, no. 4 (December 1, 1986): 286–91. http://dx.doi.org/10.1115/1.3231278.

Full text

Abstract:

A numerical study is reported on the turbulent jet flowing into closed tubes. In the computation the finite volume method is employed to solve the continuity and momentum equations with the use of the second-order closure model of turbulence. The computations were made for tube depths and tube widths ranging from 2 to 30 jet diameters and from 2 to 8 jet diameters, respectively. The computed decay of the jet centerline velocity agrees reasonably well with the experimental data (within 10 percent). With the use of the second-order closure model, it became clear that an isotropic assumption is still valid in the main mixing region in the tube. Moreover, the wall shear stress distributions were obtained along the side wall of a tube. Finally, it was found that the terminal stagnation pressure at the tube bottom depends strongly on the diameter of the tube for DT/DN of less than 5.

APA, Harvard, Vancouver, ISO, and other styles

10

Gross, Roxann Diez, Jeanne Mahlmann, and Judith P. Grayhack. "Physiologic Effects of Open and Closed Tracheostomy Tubes on the Pharyngeal Swallow." Annals of Otology, Rhinology & Laryngology 112, no. 2 (February 2003): 143–52. http://dx.doi.org/10.1177/000348940311200207.

Full text

Abstract:

Studies linking aspiration and dysphagia to an open tracheostomy tube exemplify the possibility that the larynx may have an influence on oropharyngeal swallow function. Experiments addressing the effects of tracheostomy tube occlusion during the swallow have looked at the presence and severity of aspiration, but few have included measurements that capture the changes in swallowing physiology. Also, hypotheses for the importance of near-normal subglottic air pressure during the swallow have not been offered to date. As such, the aim of this study was to compare the depth of laryngeal penetration, bolus speed, and duration of pharyngeal muscle contraction during the swallow in individuals with tracheostomy tubes while their tubes were open and closed. The results of this series of experiments indicate that within the same tracheostomized patient, pharyngeal swallowing physiology is measurably different in the absence of subglottic air pressure (open tube) as compared to the closed tube condition.

APA, Harvard, Vancouver, ISO, and other styles

11

Glass, C., MJ Grap, and CN Sessler. "Endotracheal tube narrowing after closed-system suctioning: prevalence and risk factors." American Journal of Critical Care 8, no. 2 (March 1, 1999): 93–100. http://dx.doi.org/10.4037/ajcc1999.8.2.93.

Full text

Abstract:

BACKGROUND: Few data exist about buildup of secretions within endotracheal tubes of patients treated with closed-system suctioning in the intensive care unit. OBJECTIVES: To describe the extent, prevalence, and distribution of narrowing of endotracheal tubes related to buildup of secretions and to determine contributing factors. METHODS: Forty endotracheal tubes were examined within 4 hours of extubation, after at least 72 hours of use. Data on patients' daily weight and fluid balance, ventilator humidification temperatures, and nurses' descriptions of secretions during the 3 days preceding extubation were recorded. Any secretion debris in the endotracheal tubes was weighed. At 1-cm intervals along the tube, the debris was described and the depth of the debris was measured to the nearest 0.5 mm. RESULTS: Mean duration of intubation was 6.6 days. Two tubes had no debris. Mean overall depth of debris was 0.64 mm, mean greatest depth was 2.0 mm (range, 0-5 mm), and mean weight was 1.16 g. The entire tube was affected, with the greatest depth of debris at the 6- to 9-cm and 13- to 14-cm markings. Duration of intubation correlated with mean greatest depth of debris (r = 0.37, P = .02), mean overall depth of debris (r = 0.48, P = .002), and mean weight of debris (r = 0.38, P = .02). CONCLUSIONS: Endotracheal tubes are markedly narrowed by the buildup of secretions after closed-system suctioning. Duration of intubation, but not endotracheal tube size or amount of secretions, was associated with the degree of narrowing.

APA, Harvard, Vancouver, ISO, and other styles

12

Yekani Fard, Masoud, Brian Raji, Bao Doan, Michael Brooks, John Woodward, and Collin Foster. "An experimental study of the mechanical properties of seamless and overlapped stitched composite tubes under hydrostatic pressure, lateral compression, and impact." Journal of Strain Analysis for Engineering Design 55, no. 7-8 (June 7, 2020): 212–21. http://dx.doi.org/10.1177/0309324720922749.

Full text

Abstract:

Mechanical properties and damage mechanisms of closed circular preforms and overlapped stitched composite tubes under lateral compression, impact, and hydrostatic pressure were studied. The functional failure pressures of the tubes with different boundary conditions were determined and compared. Stitch at the overlapped zone creates stress risers that lead to premature functional failure at a hydrostatic pressure at ∼1/3 of the theoretical maximum pressure of the tube as delamination occurs at the overlapping region. Seamless tubes reached values close to theoretical operating hydrostatic pressures before leakage was observed at the tube ends. The deflection of the overlapped stitched tube due to lateral compression is less than the deflection in the seamless tube, and it is limited to 5% of the inner diameter using the Spangler equation. Brittle kinks, cracks, and delamination occur in overlapped stitched tubes while seamless tubes regain the shape with limited localized cracks after unloading. The fabric architecture of a seamless tube allows for the reorientation of fiber tows as cracks develop in the matrix, thus resulting in a lesser extent of damage when the tube is subject to impact.

APA, Harvard, Vancouver, ISO, and other styles

13

LeBlanc, K. A., and W. Y. Tucker. "Prophylactic antibiotics and closed tube thoracostomy." Journal of Trauma: Injury, Infection, and Critical Care 26, no. 1 (January 1986): 97. http://dx.doi.org/10.1097/00005373-198601000-00032.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Tavares, Aline Cristina, and Pedro Nabuco De Araujo. "PRACTICAL ASPECTS ABOUT CLOSED CHEST DRAINAGE CARE: A LITERATURE REVIEW." Revista Pesquisa em Fisioterapia 7, no. 2 (May 29, 2017): 298–307. http://dx.doi.org/10.17267/2238-2704rpf.v7i2.1280.

Full text

Abstract:

Context: The drained pleural contents may vary, as well as their drainage, however closed drainage system is the most frequent one and reaches flaws along those who are in charge of their management. Objetive: Provide a comprehensive review about close chest drainage. Methods: A systematic search of the PubMed and Medline databases was conducted on closed drainage system using the following keyword combination: chest tubes AND drainage. Results: From eight hundred eight-three articles retrieved after our preliminary search, 17 articles were chosen for final analysis. Representative schemes were drawn to better understanding of the three types of chest drainage systems for pleura effusion: (i) the closed drainage system; (ii) the open drainage system; and (iii) the suction drainage system. Representative pictures were also developed in order to facilitate additional care in the field. Conclusions: Bringing information together about chest tube management in closed drainage system may imply in a better approach to the patients, minimize institutional cost, minimize material waste and promote efficient communication among the multidisciplinary staff. Understanding details about tubular tube, pig tail tube, one-way bag, one-way valve and collectors is the only way to perform a better approach to the patient who needs closed drainage system.

APA, Harvard, Vancouver, ISO, and other styles

15

NEMOTO, K., M. YANAGIDA, and T. NEMOTO. "Closed Continuous Irrigation as a Treatment for Infection in the Hand." Journal of Hand Surgery 18, no. 6 (December 1993): 783–89. http://dx.doi.org/10.1016/0266-7681(93)90246-c.

Full text

Abstract:

A method of closed irrigation has been devised to treat infections in the hand. After adequate débridement, two tubes are placed in the infected area, an inlet tube and an outlet tube. For a small infection, one tube serves both purposes. The wound is closed completely. Irrigation with saline and antibiotic solution is continued for 1 week, extended up to 3 weeks in cases of severe infection. This method has been applied in 31 cases including pyogenic tenosynovitis, tuberculous tenosynovitis, pyogenic arthritis, osteomyelitis, bite injury, crush injury and amputation stump infection. Infection healed primarily in 29 cases. Further surgery was needed in two cases which healed finally.

APA, Harvard, Vancouver, ISO, and other styles

16

Liu, Zhao, Chun Lin Hu, and Yi Wang Bao. "Effect of Preparation Process on Bending Modulus and Strength of Fiber Tubes in Radial Direction." Key Engineering Materials 726 (January 2017): 3–7. http://dx.doi.org/10.4028/www.scientific.net/kem.726.3.

Full text

Abstract:

To explore the effects of preparation process on the mechanical properties of fiber reinforced tubes in radial direction, the closed ring method was applied to assess the elastic modulus and bending strength of GFRP and CFRP prepared by winding method and pultrusion method, respectively. The results indicate that there are two obvious differences between the winding tube and the pultrusion tube: i) the elastic modulus and bending strength of the winding tube for two materials are larger than that of the pultrusion tube. It should be attributed to the position of materials under stress: the former is the fibers while the latter is the matrix; ii) the failure mode for the winding tube is brittle fracture while elastic-plastic fracture is for the pultrusion tube. Compared with other experimental methods, the results of the closed ring method are accurate and reliable, which is demonstrated to be a potential method to evaluate the mechanical properties of fiber tubes in radial direction rapidly and conveniently.

APA, Harvard, Vancouver, ISO, and other styles

17

HARRIS, P. A., and J. NANCHAHAL. "Closed Continuous Irrigation in the Treatment of Hand Infections." Journal of Hand Surgery 24, no. 3 (June 1999): 328–33. http://dx.doi.org/10.1054/jhsb.1998.0009.

Full text

Abstract:

We report our experience with a closed continuous irrigation system in 12 patients with hand infections: six cases of flexor tenosynovitis, three cases of septic arthritis and three palmar abscesses. Four of these patients had undergone previous surgical débridement and peroperative washout without elimination of the infection. The continuous irrigation system consists of two fenestrated tubes placed within the infected space, with the tip of the smaller calibre inlet tube positioned just inside the larger outlet tube. Resolution of infection was achieved in all 12 cases and all regained complete functional recovery. The closed continuous irrigation system is easy to manage, with no leakage of fluid; hand therapy may be started early and the patient is mobile throughout.

APA, Harvard, Vancouver, ISO, and other styles

18

MATALON, MOSHE, and PHILIPPE METZENER. "The propagation of premixed flames in closed tubes." Journal of Fluid Mechanics 336 (April 10, 1997): 331–50. http://dx.doi.org/10.1017/s0022112096004843.

Full text

Abstract:

A nonlinear evolution equation that describes the propagation of a premixed flame in a closed tube has been derived from the general conservation equations. What distinguishes it from other similar equations is a memory term whose origin is in the vorticity production at the flame front. The two important parameters in this equation are the tube's aspect ratio and the Markstein parameter. A linear stability analysis indicates that when the Markstein parameter α is above a critical value αc the planar flame is the stable equilibrium solution. For α below αc the planar flame is no longer stable and there is a band of growing modes. Numerical solutions of the full nonlinear equation confirm this conclusion. Starting with random initial conditions the results indicate that, after a short transient, a at flame develops when α>αc and it remains flat until it reaches the end of the tube. When α<αc, on the other hand, stable curved flames may develop down the tube. Depending on the initial conditions the flame assumes either a cellular structure, characterized by a finite number of cells convex towards the unburned gas, or a tulip shape characterized by a sharp indentation at the centre of the tube pointing toward the burned gases. In particular, if the initial conditions are chosen so as to simulate the elongated finger-like flame that evolves from an ignition source, a tulip flame evolves downstream. In accord with experimental observations the tulip shape forms only after the flame has travelled a certain distance down the tube, it does not form in short tubes and its formation depends on the mixture composition. While the initial deformation of the flame front is a direct result of the hydrodynamic instability, the actual formation of the tulip flame results from the vortical motion created in the burned gas which is a consequence of the vorticity produced at the flame front.

APA, Harvard, Vancouver, ISO, and other styles

19

Li, Lei, and Ke Lei. "Preliminary Design and Cross-Sectional Form Study of Closed-Type Concrete-Filled Steel Tube Support for Traffic Tunnel." Symmetry 12, no. 8 (August 17, 2020): 1368. http://dx.doi.org/10.3390/sym12081368.

Full text

Abstract:

In view of the structural form and common construction methods of traffic tunnels, the bearing performance of the closed-type CFST support designed for traffic tunnels is studied. The closed-type CFST support, which consist of a CFST girder with external shotcrete, is improved from the CFST support used in mine roadways. The reasonable cross-sectional form of closed-type CFST support is analyzed by the FEM. The closed-type CFST support is mainly composed of CFST arches, a shotcrete layer, sleeves, and blind flanges. The post-buckling analysis of the closed-type CFST circular arch members using circular-shaped, rectangular-shaped, triangular-shaped, and trapezoidal-shaped steel tubes is implemented. The result shows that the closed-type CFST support has better performance than the traditional tunnel support. The study also found that for closed-type CFST support, the triangular-shaped steel tube section has the highest bearing capacity, stiffness, and steel utilization rate, which is the preferred cross-sectional form. The bearing capacity of the circular-shaped steel tube section is acceptable. Moreover, the circular-shaped steel tubes are more convenient to obtain and process, so it is also an optional cross-sectional form. The square-shaped and trapezoidal-shaped steel tube sections have neither performance advantages nor economic efficiency, so these two forms are not recommended.

APA, Harvard, Vancouver, ISO, and other styles

20

Páll-Gergely, Barna, Fred Naggs, and Takahiro Asami. "Novel shell device for gas exchange in an operculate land snail." Biology Letters 12, no. 7 (July 2016): 20160151. http://dx.doi.org/10.1098/rsbl.2016.0151.

Full text

Abstract:

The operculum of terrestrial snails tightly seals the shell aperture providing protection from predators and body-water loss. To allow respiration with a closed operculum, operculate land snails repeatedly evolved shell devices such as tubes or channels that open to the air. In all Asian members of the Alycaeidae, an externally closed tube lies along the suture behind the aperture that possesses a small internal opening into the last whorl at the tube's anterior end. However, this structure presents a paradox: how is gas exchanged through an externally closed tube? Here we show that many microtunnels open into the tube and run beneath radial ribs along the growth line of the last whorl in Alycaeus conformis . These tunnels open to the outside of the shell surface near the umbilicus. Examination under high magnification revealed that the outermost shell layer forms these tunnels only in the whorl range beneath the sutural tube. Each tunnel ( ca 16 µm diameter) is far narrower than any known metazoan parasite. These findings support our hypothesis that the externally closed sutural tube functions with microtunnels as a specialized apparatus for predator-free gas exchange with minimal water loss when the operculum seals the aperture.

APA, Harvard, Vancouver, ISO, and other styles

21

Mahat, M. Mazwan, Izdihar Tharazi, Liyana Roslan, and Mohd Fakrul Jasni. "Valveless Pump in Closed Loop Tube System." Applied Mechanics and Materials 607 (July 2014): 561–64. http://dx.doi.org/10.4028/www.scientific.net/amm.607.561.

Full text

Abstract:

This research work aims to identify the characteristic of flow in valveless impedance pump which uses acoustic impedance mismatch to drive flow. The experimental setup mainly focuses on the elastic section connected between two ends of rigid tube. Fluid flow rate resulting from the pumping mechanism were measured at different supply voltage. Meanwhile, the volume flow rate (ml / min) in the elastic tube section were also determined based upon different pinch location and width using water as a working fluid. In order to achieve these parameters quantification, the experimental test rig was designed and the set of equipments were successfully assembled. Then, the measured parameters resulting from the experiment of the impedance pump are presented in significant findings of four curves plots. It is found that the maximum flow rate occurred at voltage setting equal to 4 V. Significantly, results obtained could beneficial future design as a mimics model for novel Ventricular Assist Device use in cardiac patient as well as further explanation about the factor that influence the characteristic of valveless impedance pump.

APA, Harvard, Vancouver, ISO, and other styles

22

Liew, Michael, Michael Seipp, Jacob Durtschi, Rebecca L. Margraf, Shale Dames, Maria Erali, Karl Voelkerding, and Carl Wittwer. "Closed-Tube SNP Genotyping Without Labeled Probes." American Journal of Clinical Pathology 127, no. 3 (March 2007): 341–48. http://dx.doi.org/10.1309/n7rarxh3623avkdv.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Thakur, Anjani, Terry Buchmiller, and James Atkinson. "Bronchial perforation after closed-tube endotracheal suction." Journal of Pediatric Surgery 35, no. 9 (September 2000): 1353–55. http://dx.doi.org/10.1053/jpsu.2000.9332.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Fridh, L. O., R. Thåmlitz, and A. K. Öhlin. "Experiences with the “automated closed tube sampler”." European Journal of Haematology 45, S53 (April 24, 2009): 61. http://dx.doi.org/10.1111/j.1600-0609.1990.tb01532.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Risso, F., and J. Fabre. "Axisymmetric turbulent jet in a closed tube." Experimental Thermal and Fluid Science 7, no. 2 (August 1993): 151. http://dx.doi.org/10.1016/0894-1777(93)90208-z.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Tseytlin, A. A. "Closed superstrings in magnetic flux tube background." Nuclear Physics B - Proceedings Supplements 49, no. 1-3 (June 1996): 338–49. http://dx.doi.org/10.1016/0920-5632(96)00354-4.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Manopoulos, Christos, Sokrates Tsangaris, and Dimitrios Mathioulakis. "Net flow generation in closed-loop valveless pumping." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 234, no. 11 (February 6, 2020): 2126–42. http://dx.doi.org/10.1177/0954406220904110.

Full text

Abstract:

Net flow generation in valveless pumping, met in many physiological applications and recently in micropumping devices, constitutes an open fluid dynamics issue due to the complex interaction between the fluid medium and the flexible walls of the pump. In the context of the present experimental work, the conditions of the net flow generation are examined in a closed-loop horizontal valveless pump, which consists of a rigid and an elastic tube of equal diameters and lengths, and a pincher that forces the liquid within the tube to oscillate at Reynolds and Womersley numbers up to 7800 and 48, respectively. Pinching off as well as at the mid-length of the pump flexible tube, net flow is generated at certain pinching frequencies for which details are presented based on simultaneous recording of the pressure at the two tube junctions, the flow rate and the displacement of the pincher. Pinching off the mid-length of the pump at low pinching frequencies, net flow rate is practically null due to the almost identical pressure waveforms at the tube junctions, which vary in phase with the pincher motion. However, close to the first natural frequency of the hydraulic loop, the reflection of the pressure waves at the tube junctions combined with their increased phase difference cause high axial pressure gradients, which when they increase simultaneously with the squeezing of the tube, net flow rate maximization occurs. Pinching at the flexible tube mid-length area, nonzero net flow rates can also be generated, the sign of which changes when the pincher mid-point crosses the tube mid-length without being nullified.

APA, Harvard, Vancouver, ISO, and other styles

28

Gowda, Narasimhe, B. Putta Bore Gowda, R. Chandrashekar, G. Ugrasen, and R. Keshavamurthy. "Experimental Investigation of Evacuated Tube Solar Collector with Annular Heat Exchanger." Applied Mechanics and Materials 592-594 (July 2014): 2355–59. http://dx.doi.org/10.4028/www.scientific.net/amm.592-594.2355.

Full text

Abstract:

Now-a-days evacuated tubes solar water heaters are increasingly use in South India because of good thermal efficiency and high water temperature could be achievable as compared to flat plate solar collectors. Low manufacturing and maintenance cost also attract people to go for evacuated tube solar water heaters. This paper reports experimental results of two types of evacuated tube solar water heaters. To evaluate the performance of evacuated tube solar water heater, single-phase forced system and two-phase closed forced systems were considered. In two-phase closed system sunflower oil was used as working fluid to heat water. Throughout the study two-phase closed system shows better performance compared to single-phase open collector system and their efficiency almost 10 to 12% higher. But, because of high initial cost of two-phase system, the pay back periods of both collector systems is almost same. In two phased closed system higher temperature of water could be achieved, which is very useful to operate advanced system.

APA, Harvard, Vancouver, ISO, and other styles

29

Uzun, A. "Compressive Crush Performance of Square Tubes Filled with Spheres of Closed-Cell Aluminum Foams." Archives of Metallurgy and Materials 62, no. 3 (September 26, 2017): 1755–60. http://dx.doi.org/10.1515/amm-2017-0267.

Full text

Abstract:

AbstractThis paper describes the compressive crush behaviour of spheres of closed-cell aluminium foams with different diameters (6, 8 and 10 mm) and square tubes filled with these spheres. The spheres of closed-cell aluminium foams are net spherical shape fabricated via powder metallurgy methods by heating foamable precursor materials in a mould. The square tubes were filled by pouring the spheres of closed-cell aluminium foams freely (without any bonding). The compressive crush performance of square tubes filled with spheres of closed-cell aluminum foams were compared to that of the empty tubes. The results show a significant influence of the spheres of closed-cell aluminium foam on the average crushing load of the square tubes. The energy absorption in the square tube filled with spheres of closed-cell aluminium foam with diameters of 10 mm is higher than in the other square tubes. The spheres of closed-cell aluminium foams led to improvement of the energy absorption capacity of empty tubes.

APA, Harvard, Vancouver, ISO, and other styles

30

Jiang, W. "The Elastic-Plastic Analysis of Tubes—I: General Theory." Journal of Pressure Vessel Technology 114, no. 2 (May 1, 1992): 213–21. http://dx.doi.org/10.1115/1.2929032.

Full text

Abstract:

A study is made in this paper of the elastic-plastic analysis of tubes subjected to various loads and temperatures. The kinematic hardening rule is used in the analysis and constitutive equations are developed for the tube problems. By piecing several elastic and plastic solutions together, various tube problems can be solved in closed forms.

APA, Harvard, Vancouver, ISO, and other styles

31

HORIE, Yosuke, and Takamichi MORI. "Development of micro sampling nozzle for closed tube." Transactions of the JSME (in Japanese) 83, no. 849 (2017): 16–00579. http://dx.doi.org/10.1299/transjsme.16-00579.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Eddy, J. K., J. N. Fox, N. W. Gaggini, D. Ramsey, and T. Kirkpatrick. "The velocity of sound in a closed tube." American Journal of Physics 55, no. 12 (December 1987): 1136–38. http://dx.doi.org/10.1119/1.15261.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Chance, Aaron, and David I. Sandberg. "Hydrocephalus in patients with closed neural tube defects." Child's Nervous System 31, no. 2 (July 16, 2014): 329–32. http://dx.doi.org/10.1007/s00381-014-2492-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Lock, G. S. H., and R. D. Abdurahman. "Heat transfer characteristics of the closed tube aerosyphon." International Journal of Heat and Mass Transfer 31, no. 1 (January 1988): 143–52. http://dx.doi.org/10.1016/0017-9310(88)90231-1.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Lock, G. S. H., and J. D. Kirchner. "Performance of a Closed-Tube Aerosyphon With Large Length-Diameter Ratios." Journal of Offshore Mechanics and Arctic Engineering 111, no. 4 (November 1, 1989): 337–43. http://dx.doi.org/10.1115/1.3257104.

Full text

Abstract:

The paper reports an experimental investigation of heat transfer in the closed-tube aerosyphon (aerated-thermosyphon) for a range of conditions representative of northern field applications. In particular, attention is focused on the effect of using tubes with heated lengths not only greater than the cooled lengths, but very much greater than the tube diameter. Using three heated sections and one cooled section, the geometry of the device has been varied systematically with 10 < LH/d < 50 and 1 < LH/LC < 20. For any given geometry, the effect of air bubbling rate has been studied in the range of 0 < V˙ < 5 × 10−5 m3/S. Using these ranges it has been possible to make comparisons with other thermosyphon and aerosyphon data. The results indicate that heat transfer coefficients are reduced by increasing either length-diameter ratio or heated-cooled length ratio. They also reveal that, in general terms, the aerosyphon is almost an order-of-magnitude more effective than the single-phase thermosyphon. Some obervations on the flow regimes are offered, and an empirical correlation is presented.

APA, Harvard, Vancouver, ISO, and other styles

36

Kim, Yong Won, Chun Sung Byun, Yong Sung Cha, Oh Hyun Kim, Kang Hyun Lee, and Il Hwan Park. "Differential Outcome of Fissure-positioned Tube in Closed Thoracostomy for Primary Spontaneous Pneumothorax." American Surgeon 81, no. 5 (May 2015): 463–66. http://dx.doi.org/10.1177/000313481508100526.

Full text

Abstract:

Closed tube thoracostomy is often used to evacuate a primary spontaneous pneumothorax (PSP). Occasionally, this procedure is complicated by placement of the chest tube location in the fissural area instead of pleural space. There is a paucity of studies on outcomes according to chest tube placement. As such, we investigated outcomes of chest tube placement in fissural versus pleural area in closed thoracostomy for PSP. Patients between 14 and 65 years of age who had been treated with chest tube insertion to evacuate PSP were selected based on retrospective review of medical records. Patients selected for this study received chest tube placement at either the fissural or pleural spaces. Those with pre-existing lung disease or those transferred into our hospital after closed thoracostomy were excluded. Of the 255 patients with PSP treated with chest tube insertion, 172 patients were enrolled in this study. Twenty-nine (16.9%) had fissural tube placement and 143 (83.1%) had pleural tube placement. A higher proportion of patients in the fissural versus pleural group required additional chest tube insertion (20.7% vs 4.9%, P = 0.010, respectively). There was no significant difference in body mass index, smoker status, symptom duration, number of episodes, post-thoracostomy complications, need for subsequent management, and duration of hospitalization in either group. In closed thoracostomy for PSP, there is a higher chance of tube dysfunction when the chest tube is positioned at fissural area as compared with the pleural space.

APA, Harvard, Vancouver, ISO, and other styles

37

Hart, J. E. "Observations of Complex Oscillations in a Closed Thermosyphon." Journal of Heat Transfer 107, no. 4 (November 1, 1985): 833–39. http://dx.doi.org/10.1115/1.3247511.

Full text

Abstract:

Observations have been made of thermal oscillations in a slightly inclined closed thermosyphon. The thermosyphon is made up of two isothermal tubes, capped at the outer ends, and joined along their axes by an insulating section. The tube assembly is filled with liquid and inclined slightly with respect to the vertical. The lower isothermal section is hotter than the upper one and convection is driven across the insulating region. Between the applied temperature difference at which simple steady convection occurs, and that required for persistent turbulent motions, there is a wide range over which thermal oscillations are observed. These oscillations reflect quasi-periodic flow as well as a type of periodic chaos.

APA, Harvard, Vancouver, ISO, and other styles

38

Petersen, A. L. "A device for easy removal of tubes from the “automated closed tube sampler”." European Journal of Haematology 45, S53 (April 24, 2009): 62. http://dx.doi.org/10.1111/j.1600-0609.1990.tb01533.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

FUENTES, O. U. VELASCO. "On the topology of vortex lines and tubes." Journal of Fluid Mechanics 584 (July 25, 2007): 147–56. http://dx.doi.org/10.1017/s0022112007006945.

Full text

Abstract:

This paper examines the widespread idea that vortex lines and tubes must either close on themselves or extend to the boundary of the fluid. A survey of the origins of this misconception, and of earlier attempts to set it right, is followed by an analysis of simple flows exhibiting vortex lines and tubes which do not fit those shapes. Two types of vortex lines are discussed: dense, which comprise open lines of infinite length but confined in a finite region, and separatrix, which comprise lines that begin or finish within the fluid, at points where the vorticity is null. The presence of these vortex lines in a vortex tube affects its topology in the following ways. Vortex tubes formed by dense vortex lines have infinite length; they self-intersect an infinite number of times but do not close on themselves. Vortex tubes formed by separatrix vortex lines (and either closed or open vortex lines) are torn apart at the points where the vorticity is null. Vortex tubes exclusively composed of separatrix vortex lines begin or finish at points or surfaces within the fluid; in this particular situation the vortex tube has zero strength.

APA, Harvard, Vancouver, ISO, and other styles

40

Bauwens, Luc. "Oscillating flow of a heat-conducting fluid in a narrow tube." Journal of Fluid Mechanics 324 (October 10, 1996): 135–61. http://dx.doi.org/10.1017/s0022112096007860.

Full text

Abstract:

Thermoacoustic refrigeration occurs in periodic flow in a duct with heat transfer within the fluid and to the tube. This study considers the periodic limit cycle with large pressure oscillations that is obtained in a tube when prescribed, phase-shifted, periodic velocities at the tube ends, at frequencies lower than acoustic eigenmodes, sweep a length comparable to the tube length. The temperature differences between the two ends are of arbitrary magnitude, heat transfer in the transverse direction within the fluid is assumed to be very effective and the thermal mass of the wall is large. The geometry is two-dimensional, axisymmetric, and conduction is accounted for, not only in the fluid, but also with and within the tube wall. A perturbation solution valid in a local near-isothermal limit determines the equilibrium longitudinal temperature profile that is reached at the periodic regime, the pressure field including longitudinal gradients, and the longitudinal enthalpy flux. Results are presented for tubes open at both ends and also with one end closed. In the latter case, a singularity occurs in the temperature at the closed end, with behaviour identical to Rott's result for acoustic flow with small pressure amplitude. Other new results obtained for tubes open at both ends show that when velocities at both ends are in opposite phase, internal singularities in the temperature profiles may occur.

APA, Harvard, Vancouver, ISO, and other styles

41

Shukhobodskiy, A. A., and M. S. Ruderman. "Resonant damping of kink oscillations of thin expanding magnetic tubes." Astronomy & Astrophysics 615 (July 2018): A156. http://dx.doi.org/10.1051/0004-6361/201732396.

Full text

Abstract:

We study the resonant damping of kink oscillations of thin expanding magnetic flux tubes. The tube consists of a core region and a thin transitional region at the tube boundary. The resonance occurs in this transitional layer where the oscillation frequency coincides with the local Alfvén frequency. Our investigation is based on the system of equations that we previously derived. This system is not closed because it contains the jumps of the magnetic pressure perturbation and plasma displacement across the transitional layer. We calculate these jumps and thus close the system. We then use it to determine the decrements of oscillation eigenmodes. We introduce the notion of homogeneous stratification. In accordance with this condition the ratio of densities in the tube core and outside the tube does not vary along the tube, while the density in the transitional layer can be factorised and written as a product of two function, one depending on the variable along the tube and the other on the magnetic flux function. Our main result is that, under the condition of homogeneous stratification, the ratio of the decrement to the oscillation frequency is independent of a particular form of the density variation along the tube. This ratio is also the same for all oscillation eigenmodes.

APA, Harvard, Vancouver, ISO, and other styles

42

Homae, Tomotaka, Yuta Sugiyama, Kei Shimura, Kunihiko Wakabayashi, Tomoharu Matsumura, and Yoshio Nakayama. "Blast mitigation by water in a bag on a tunnel floor." MATEC Web of Conferences 192 (2018): 02039. http://dx.doi.org/10.1051/matecconf/201819202039.

Full text

Abstract:

Mitigation of blast wave, caused by explosion of explosives, from a straight tube using water in a bag (water bag) was evaluated. The length of the tube was 330 mm and the cross-section area was 30 x 30 mm2. One end of the tube was closed. The water bag was placed on the floor or closed end wall of the tube near the explosive. The thickness of water was 3 mm. A specially designed small detonator, which contains lead azide of 100 mg, was ignited near the closed end wall of the tube. The blast pressure outside the tube was measured and examined. The blast wave was remarkably mitigated by the water bag. Equivalent ratio analysis revealed that the glass beads absorbed 33%-45% of explosion energy.

APA, Harvard, Vancouver, ISO, and other styles

43

Gong, Dawei, Craig A. Grimes, Oomman K. Varghese, Wenchong Hu, R. S. Singh, Zhi Chen, and Elizabeth C. Dickey. "Titanium oxide nanotube arrays prepared by anodic oxidation." Journal of Materials Research 16, no. 12 (December 2001): 3331–34. http://dx.doi.org/10.1557/jmr.2001.0457.

Full text

Abstract:

Titanium oxide nanotubes were fabricated by anodic oxidation of a pure titanium sheet in an aqueous solution containing 0.5 to 3.5 wt% hydrofluoric acid. These tubes are well aligned and organized into high-density uniform arrays. While the tops of the tubes are open, the bottoms of the tubes are closed, forming a barrier layer structure similar to that of porous alumina. The average tube diameter, ranging in size from 25 to 65 nm, was found to increase with increasing anodizing voltage, while the length of the tube was found independent of anodization time. A possible growth mechanism is presented.

APA, Harvard, Vancouver, ISO, and other styles

44

Lovlya, Ekaterina V., and Oleg A. Popov. "Power Losses in RF Inductor of Ferrite-Free Closed-Loop Inductively-Coupled Low Pressure Mercury Lamps." Volume 28, Number 2, 2020, no. 02-2020 (April 2020): 89–94. http://dx.doi.org/10.33383/2019-040.

Full text

Abstract:

RF inductor power losses of ferrite-free electrode-less low pressure mercury inductively-coupled discharges excited in closed-loop dielectric tube were studied. The modelling was made within the framework of low pressure inductive discharge transformer model for discharge lamps with tubes of 16, 25 and 38 mm inner diam. filled with the mixture of mercury vapour (7.5×10–3 mm Hg) and argon (0.1, 0.3 and 1.0 mm Hg) at RF frequencies of 1, 7; 3.4 and 5.1 MHz and plasma power of (25–500) W. Discharges were excited with the help of the induction coil of 3, 4 and 6 turns placed along the inner perimeter of the closed-loop tube. It was found that the dependence of coil power losses, Pcoil, on the discharge plasma power, Ppl, had the minimum while Pcoil decreased with RF frequency, tube diameter and coil number of turns. The modelling results were found in good qualitative agreement with the experimental data; quantitative discrepancies are believed to be due skin-effect and RF electric field radial inhomogeneity that were not included in discharge modelling.

APA, Harvard, Vancouver, ISO, and other styles

45

Hu Peng, 胡鹏, 苏华 Su Hua, 安建祝 An Jianzhu, and 张飞舟 Zhang Feizhou. "Thermal coupling effects on laser propagaton in closed tube." High Power Laser and Particle Beams 25, no. 7 (2013): 1651–56. http://dx.doi.org/10.3788/hplpb20132507.1651.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Tokunaga, T. K., L. J. Waldron, and J. Nemson. "A Closed Tube Method for Measuring Gas Diffusion Coefficients." Soil Science Society of America Journal 52, no. 1 (January 1988): 17–23. http://dx.doi.org/10.2136/sssaj1988.03615995005200010003x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Pacanowski, John P., Matthew L. Waack, Brian J. Daley, Karen S. Hunter, Richard Clinton, Daniel L. Diamond, and Blaine L. Enderson. "Is Routine Roentgenography Needed after Closed Tube Thoracostomy Removal?" Journal of Trauma: Injury, Infection, and Critical Care 48, no. 4 (April 2000): 684–88. http://dx.doi.org/10.1097/00005373-200004000-00016.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

YANO, Takeru, Tatsuya ISHIYAMA, and Yoshinori INOUE. "Acoustic Levitation of a Sphere in a Closed Tube." Proceedings of the Fluids engineering conference 2000 (2000): 119. http://dx.doi.org/10.1299/jsmefed.2000.119.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Ji, Z. L. "Acoustic length correction of closed cylindrical side-branched tube." Journal of Sound and Vibration 283, no. 3-5 (May 2005): 1180–86. http://dx.doi.org/10.1016/j.jsv.2004.06.044.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Brigden, Malcolm L., and Norma E. Page. "Three Closed-Tube Methods for Determining Erythrocyte Sedimentation Rate." Laboratory Medicine 24, no. 2 (February 1, 1993): 97–102. http://dx.doi.org/10.1093/labmed/24.2.97.

Full text

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!