Gotowa bibliografia na temat „SUBMERGENCE DEPTH”
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Zobacz listy aktualnych artykułów, książek, rozpraw, streszczeń i innych źródeł naukowych na temat „SUBMERGENCE DEPTH”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Artykuły w czasopismach na temat "SUBMERGENCE DEPTH"
1
Tang, Long, Bo Li, Bin Zhao, Peng Li, Zhanbin Li i Yang Gao. "Invasive Smooth Cordgrass (Spartina alterniflora) Eradication and Native Crab Recovery". Invasive Plant Science and Management 11, nr 2 (czerwiec 2018): 89–95. http://dx.doi.org/10.1017/inp.2018.13.
Pełny tekst źródłaStreszczenie:
AbstractInvasive smooth cordgrass (Spartina alterniflora Loisel) eradication is important for the health of many coastal ecosystems. An integrated regime of continuous submergence after clear mowing, with three interval levels between mowing and submergence (5, 10, and 15 d) and three submergence depths (20, 30, and 50 cm), was implemented in cofferdams enclosing invader populations along a Chinese coast. In July of the following year, after the roots of mowed S. alterniflora had been submerged for 12 mo, some ramets grew under the regime with an interval of 15 d and the regime with a submergence depth of 20 cm, but no ramets occurred under the regimes with submergence depths of 30 or 50 cm and intervals of 5 or 10 d. Four crab species were documented: Helice tridens tientsinensis Rathbun, Sesarma dehaani H. Milne-Edwards, Ocypode stimpsoni Ortmann, and Chiromantes haematocheir de Haan. Biomass and abundance values of crab species in the cofferdams were similar to those in the mudflats but different from those in smooth cordgrass populations. Thus, the treatment of submergence after mowing, which was implemented in the cofferdams, can control S. alterniflora and provide a mudflat-like habitat that promotes crab recovery if this treatment uses the proper combination of submergence depth and interval between mowing and submergence.
2
Aka, Mfoniso U., Okechukwu E. Agbasi, Okonna Nsidibe Ndaraka i Osu Azuanamibebi Derikuma. "Assessment of Geologic Effect of Road Submergence Depths on Soil Subgrade Strength in Eket, South-South Nigeria". International Journal of Scientific Research and Management 10, nr 06 (21.06.2022): 09–21. http://dx.doi.org/10.18535/ijsrm/v10i6.g1.
Pełny tekst źródłaStreszczenie:
Road submergence is a common occurrence in Eket, South-South Nigeria, resulting in massive outlays for road construction and alimony. Fundamentally, the delineation of roadway structures is based on the strength of consolidated soil avowed as the subgrade. Consequently, the subgrade is the in situ material upon which the roadway structure is placed. It is necessary to know the modes of damage to roads caused by submergence. This study assesses the effect of road submergence depths and the extent of submergences on the subgrade strength of soil samples carried out on the Uquo Eket road that was intensely defective by the deluge. Coherent and frictional soil material types were tested for California Bearing ratio (CBR), mechanical analysis, Atterberg limit determination, and moisture density tests, respectively. CBR tests were done at various elevations of submersion, including common drenching limit, elongated deluge, and resoluteness of its suitability. Atterberg limit determination and mechanical analysis tests categorized and determined the applicability of studious soil as subgrade substantial. For elongated duration deluges, the depth and extent of submergence of subgrade strength show a lower value. Moreover, mechanical and Atterberg limit determination tests indicate a rapid and high-resolution occurrence of delegation for the elongated duration.
3
Kadhim, Ali F., i Hayder A. Al Thamiry. "Computation of Critical Submergence Depth to Avoid Surface Vortices at Vertical Pumps Intakes". Journal of Engineering 26, nr 8 (1.08.2020): 59–68. http://dx.doi.org/10.31026/j.eng.2020.08.05.
Pełny tekst źródłaStreszczenie:
The pumping station became widely used in many fields. Free surface vortices at intakes of pumps are not favorable. It may cause noise, excessive vibration, damage to the pumping structure, reduction in efficiency and flow for hydro-turbines, etc. One of the important problems encountered during the pump intake design is the depth of submergence and other design parameters to avoid strong free-surface vortices formation. This study aims to compute the critical submergence depth with some geometrical and hydraulic limitations by using Computational Fluid Dynamic (CFD) package. The mathematical model was validated with a laboratory model that had been conducted. The model of three intake pipes was investigated under five different submergence depth (S), three different spaces between intake pipes (b), and five different suction velocities (v). The results showed the best operation cases when the space between intake pipes (b) equal to 4D, the submergence depth of water is equal or greater than 1.25 from the bell mouth diameter of intake pipe (D), and the suction velocity less than 2 m/s. The worst case was when the space between the suction pipe (b) was (2D), in this case, the vortex appeared at submergence depth (S/D = 2) with suction velocity 3 m/s.
4
Zhang, Hu Zhu, i Hui Min Li. "Influencing Factors Analysis on Sunken Greenbelt Design of Urban Road". Applied Mechanics and Materials 638-640 (wrzesień 2014): 1158–61. http://dx.doi.org/10.4028/www.scientific.net/amm.638-640.1158.
Pełny tekst źródłaStreszczenie:
In order to provide scientific basis for the design parameters’ selection of sunken greenbelt of urban road, computational formulae of critical sunken depth and sunken greenbelt plant’s submergence time were derived based on the storage-infiltration analysis of sunken greenbelt. And then the influence of various factors on the sunken greenbelt design of urban road were computed and analyzed. Results show that: soil infiltration coefficient, design recurrence interval of storm and sunken greenbelt plant’s submergence time are the key influencing factors on the sunken greenbelt design. Under the same condition, critical sunken depth decreases linearly with the increase of soil infiltration coefficient, and increases nonlinearly with the increase of design recurrence interval of storm. Sunken greenbelt plant’s submergence time is proportional to sunken depth of sunken greenbelt, and it is inversely proportional to soil infiltration coefficient. When the value of soil infiltration coefficient is greater than 10-6m/s and the sunken depth range from 0 to 0.25 meters, submergence time of sunken greenbelt plants is all within 70h, and the sunken greenbelt can most infiltrate the rainfall storage in 1d. Considering all the influencing factors, soil infiltration coefficient of sunken greenbelt of urban road should be greater than10-6m/s and the appropriate sunken depth should be range from 0 to 0.25 meters.
5
Chu, Yuhang, Rui Li i Xiaozhang Li. "Analysis of Seismic Response of the Arch Bridge across Reservoir considering Fluid-Solid Coupling Effect". Shock and Vibration 2022 (26.12.2022): 1–15. http://dx.doi.org/10.1155/2022/3873935.
Pełny tekst źródłaStreszczenie:
Most of the deep-water bridges in Chinese reservoirs are concentrated on rivers in the southwest region. The unique structural characteristics of arch bridges are more in line with the geological topography requirements of deep reservoir areas, making them the bridge type of choice for bridges in deep reservoir areas. While the southwest region is an earthquake-prone area, in order to study the safety of arch bridges across deep water in the reservoir area, it is necessary to analyze the effect of water under seismic behavior on the box section arch ring and explore the effect of arch inundation depth on the dynamic response of arch bridges in the reservoir area. In this study, the effect of fluid-solid coupling is considered, the modified Morison equation is used to calculate the hydrodynamic pressure, and the effect of arch bridge inundation depth on the dynamic response is analyzed based on the Midas/civil finite element model of the arch bridge in the Yunnan reservoir area. The results show that the seismic response of the arch bridge across the reservoir is greatly influenced by the submergence depth of the arch bridge due to the fluid-solid coupling effect, and the influence of the hydrodynamic pressure on the longitudinal moment (My) and transverse moment (Mz) of the arch bridge increases with the increase of the submergence depth. There is a threshold value of the submergence depth. When the submergence depth is less than the threshold, the effect of fluid-solid coupling is negligible, and when the submergence depth is greater than the threshold, the fluid-solid coupling effect is significant. The thresholds for different parts of the main arch ring are different. The most unfavorable water depth in different parts of the main arch ring is not necessarily the water depth when the arch ring is completely submerged. Based on this result, for reservoir arch bridges in high intensity areas, it is recommended that the inundation depth of arch bridges crossing deep water reservoirs should be h/f less than or equal to 5/8 f.
6
Petikidis, Nikos, i George Papadakis. "Investigation of Submergence Depth and Wave-Induced Effects on the Performance of a Fully Passive Energy Harvesting Flapping Foil Operating Beneath the Free Surface". Journal of Marine Science and Engineering 11, nr 8 (7.08.2023): 1559. http://dx.doi.org/10.3390/jmse11081559.
Pełny tekst źródłaStreszczenie:
This paper investigates the performance of a fully passive flapping foil device for energy harvesting in a free surface flow. The study uses numerical simulations to examine the effects of varying submergence depths and the impact of monochromatic waves on the foil’s performance. For the numerical simulations, a in-house artificial compressibility two-phase solver is employed and coupled with a rigid body dynamic solver. The results show that the fully passive flapping foil device can achieve high efficiency for submergence depths between 4 and 9 chords, with an “optimum” submergence depth where the flapping foil performance is maximised. The effects of regular waves on the foil’s performance were also investigated, showing that waves with a frequency close to that of the natural frequency of the flapping foil-aided energy harvesting. Overall, this study provides insights that could be useful for future design improvements for fully passive flapping foil devices for energy harvesting operating near the free surface.
7
Poursorkhabi, Ramin Vafaei, i Roghayeh Ghasempour. "Possibilities to use the meta model and classical approaches to evaluate the impact of hydraulic conditions in prediction of the critical submergence depth ratio". Water Supply 19, nr 4 (10.09.2018): 1055–65. http://dx.doi.org/10.2166/ws.2018.153.
Pełny tekst źródłaStreszczenie:
Abstract One of the hydraulic phenomena that mainly occurs during the water withdrawal process of channels is the formation of vortices that can cause many problems for the hydro-mechanical facilities of intakes. In the current study, classical models and meta model approaches (i.e. Support Vector Machine and Gene Expression Programming) were applied to evaluate the impact of pipe diameter and hydraulic condition changes in prediction of the critical submergence depth ratio in horizontal intakes. In this regard, two types of critical submergence experiments, based on bottom clearance, were considered (i.e. c = 0 and c = d/2, in which c and d are the bottom clearance and diameter of the intake, respectively). Different models were developed and tested using experimental data series. The results indicated that in modeling the critical submergence depth ratio, meta model approaches led to better predictions compared to the classical approaches. It was observed that the developed models for the state of c = d/2 yielded better results. According to the outcome of sensitivity analysis, the ratio of velocities in the intake pipe and channel (Vi/Vc) had a key role in the modeling. It was also found that intake pipe diameter affected the critical submergence depth ratio in intake pipes. Increasing pipe diameter caused a decrease in model accuracy.
8
TUCK, E. O., i D. C. SCULLEN. "Tandem submerged cylinders each subject to zero drag". Journal of Fluid Mechanics 364 (10.06.1998): 211–20. http://dx.doi.org/10.1017/s0022112098001141.
Pełny tekst źródłaStreszczenie:
Two identical circular cylinders are submerged to the same depth in tandem in a stream. There are separation distances between the cylinder centres such that the combination makes no downstream waves, and hence is subject to zero net wave drag. In general there is then a non-zero equal and opposite horizontal force on each cylinder. However, there are special depths of submergence such that this interaction force between the cylinders also vanishes, and hence each cylinder is separately free of horizontal force. The parameter range for this phenomenon is explored both by linear theory for cylinders of small radius, and by a fully nonlinear computer program. For example, a configuration with a separation distance of approximately one half-wavelength gives zero force on each cylinder when the depth of submergence is approximately three-quarters of the separation distance.
9
Liu, Tianshi, Xue Tian, Liwen Liu, Xiaoyu Gu, Yun Zhao, Liumei Zhang i Xinai Song. "Modeling the Submergence Depth of Oil Well States and Its Applications". Applied Sciences 12, nr 23 (2.12.2022): 12373. http://dx.doi.org/10.3390/app122312373.
Pełny tekst źródłaStreszczenie:
Obtaining the liquid storage state of oil wells in real time is very important for oilfield production. In this paper, under the premise of fully considering the transformation factors of full-pumping and nonfull-pumping states of oil wells, submergence depth models suitable for full- and nonfull-pumping wells are constructed. To reduce the application complexity of the models, parameter-reduction processing is performed to enhance the usability of the models. By analyzing the change trend of the submergence depth during the rising, maintaining, and falling of the oil well in the full-pumping state and nonfull-pumping state models, the judgment criteria for the transition of the oil well state are provided. On this basis, the application methods of nonlinear interpolation and least squares curve-fitting numerical solutions of submergence depth models are studied, and the unique existence of the solution of the corresponding one-variable nonlinear characteristic equation in the (0, 1) open interval is proven. Finally, the error estimation of the numerical solution is carried out, the calculation formula of the number of iterations for the numerical solution of the dichotomy is provided, and the error of the relevant numerical solution is verified.
10
Hays, G. C., S. Åkesson, A. C. Broderick, F. Glen, B. J. Godley, P. Luschi, C. Martin, J. D. Metcalfe i F. Papi. "The diving behaviour of green turtles undertaking oceanic migration to and from Ascension Island: dive durations, dive profiles and depth distribution". Journal of Experimental Biology 204, nr 23 (1.12.2001): 4093–98. http://dx.doi.org/10.1242/jeb.204.23.4093.
Pełny tekst źródłaStreszczenie:
SUMMARY Satellite telemetry was used to record the submergence duration of green turtles (Chelonia mydas) as they migrated from Ascension Island to Brazil (N=12 individuals) while time/depth recorders (TDRs) were used to examine the depth distribution and dive profiles of individuals returning to Ascension Island to nest after experimental displacement (N=5 individuals). Satellite telemetry revealed that most submergences were short (<5 min) but that some submergences were longer (>20 min), particularly at night. TDRs revealed that much of the time was spent conducting short (2–4 min), shallow (approximately 0.9–1.5 m) dives, consistent with predictions for optimisation of near-surface travelling, while long (typically 20–30 min), deep (typically 10–20 m) dives had a distinctive profile found in other marine reptiles. These results suggest that green turtles crossing the Atlantic do not behave invariantly, but instead alternate between periods of travelling just beneath the surface and diving deeper. These deep dives may have evolved to reduce silhouetting against the surface, which would make turtles more susceptible to visual predators such as large sharks.
Rozprawy doktorskie na temat "SUBMERGENCE DEPTH"
1
RAWAT, ADITI RAWAT. "CFD ANALYSIS OF VORTICES AT THE SUCTION PIPE". Thesis, 2017. http://dspace.dtu.ac.in:8080/jspui/handle/repository/16050.
Pełny tekst źródłaStreszczenie:
The primary goal of this study is to comprehend the occurrence and characteristics of vortices around the suction pipe of a pump sump system. The study is carried out by conducting numerical studies using CFD (Computational Fluid Dynamics). This study is done in two phases, in first phase, comparison of three CFD models i.e. standard k-ℇ model, reliable k-ℇ model and shear stress transport model is conducted, where in second phase comparison on occurrence and characteristics of vortices for different submergence depth i.e. 300mm, 130mm and 50 mm are done. For the first case, model is scaled down to 1:10 and considered one suction pipe of a sump chamber and for the second case, model is scaled down to 1:12 which consist three suction pipe and a sump. The model comparison case suggested that shear stress transport model is a better model than the k-ℇ models, but in between k-ℇ models, standard k-ℇ model is better than the reliable k-ℇ model. This comparison is done on the basis of accumulated time step, volume fraction of water, vorticity, pressure distribution and turbulent kinetic and dissipation energy, where there maximum and minimum values were compared according to their occurrence on time step. For the submergence depth case, comparison of characteristics of vortices and swirl angle calculation are carried out. Swirl angle at all three suction pipe is calculated and compared for all three different submergence depth. Swirl angle for suction pipe 2 for depth 300mm, 130mm and 50mm are 3⁰, 6⁰ and 8⁰, where it can be said that swirl angle is decreasing with the increase in submergence depth. According to HI standard 1998, the permitted maximum swirl angle is 5⁰, so with reference to HI standards CFD analysis produced desirable results for suction pipe 2 at 300mm depth. But when studied as a system, there is decrease in swirl angle with increase in submergence depth, but, the swirl angle is not less than 5⁰. There is a validation of model of scale 1:12 is done with the obtained result from a journal of Korea university1, for swirl angle and location of vortex core region. The study in this report helps to visualize the occurrence, location and time variation of vortices around the suction pipe and the effect of change in submergence depth on vortices and characteristics of vortices.
2
Barannyk, Oleksandr. "Effect of chordwise flexibility and depth of submergence on an oscillating plate underwater propulsion system". Thesis, 2009. http://hdl.handle.net/1828/3094.
Pełny tekst źródłaStreszczenie:
The first part of this work was dedicated to the experimental study of basic principles of oscillating plate propulsors undergoing a combination of heave translation and pitch rotation. The oscillation kinematics are inspired by swimming mechanisms
employed by fish and some other marine animals. The primary attention was the
propulsive characteristics of such oscillating plates, which was studied by means of direct force measurements in the thrust-producing regime.
Experiments were performed at constant Reynolds number and heave amplitude.
By varying the Strouhal number, experimental depth and chordwise exibility of the
plate it was possible to investigate corresponding changes in thrust and hydromechanical efficiency. After numerous measurements it was possible to establish an optimal set of parameters, including the system's driving frequency, the ratio of rigid to flexible segment length of the plate and the range of Strouhal number, that led to a peak efficiency near 80%.
The experiments for different values of chordwise flexibility showed that greater
flexibility increases the propulsive effciency and thrust compared with similar motion of the purely rigid foil. By submerging the plate at different depths, it was observed that the proximity of the propulsor to the channel floor led to overall increase in the thrust coefficient. However the increase in thrust coefficient was pronounced in the range from middepth to the floor of the water tunnel. The special case when the upper plate's edge is tangential to the undisturbed free surface is discussed separately.
The second part of this work introduces a semianalytic approach for calculating
the influence of piezoelectric (PZT) actuators on the free vibration characteristics of an Euler-Bernoulli clamped free beam. The beam represents a simplifled version of the fish tail whose stiffness is proposed to be controlled by placing a pair of PZT actuators
in strategic regions along the caudal area of the tail. This approach, according to
earlier studies, improves efficiency if tail natural frequency matches tailbeat frequency.
The approach used an existing form of a transfer matrix technique developed for
the analysis of non-proportionally damped slender beams. The PZT dynamics were
incorporated into this recursive procedure through a modification that accounted for
the tendency of the PZT patches to couple the dynamics of the node points of the
segmented Euler-Bernoulli beam. To ensure stability of the system, an angular ve-
locity feedback law, originally motivated by vibration suppression applications, was
chosen for the PZT actuators. The sensitivities of the tail modes of vibration to the location of the PZT elements and the control gain were determined. Mode shapes for
the revised modes were determined and it was shown that the first, second and the
third modes maintained similar norms as tail shapes observed in anguilliform, sub-
carangiform, and thunniform regimes of swimming. Using a semianalytic approach,
it was shown that PZT location heavily in
uences the frequency distribution of the
modes of vibration. The control gain, when chosen within the limit of saturation
voltage, is shown to be an effective control lever for vibration suppression and at
rising the tail stiffness during rapid acceleration when the fish accelerates. However, the single PZT patch does not provide significant frequency adjustments such that different swimming modes could be employed efficiently with a single mechanical tail system primary actuator. To pursue such versatility for the sh tail, the tail structure must be very flexible to accommodate the significant frequency increase caused by the addition of the PZT material. Also, the use of additional PZT patches and negative control gains must be considered in order to use the PZT's to drop the higher modes (second and third) down into the frequency range of the primary actuation system, presuming the tail and primary actuator are designed for a thunniform regime of swimming.
3
Dawson, E. "An investigation into the effects of submergence depth, speed and hull length-to-diameter ratio on the near surface operation of conventional submarines". Thesis, 2014. https://eprints.utas.edu.au/22368/1/Whole-Dawson-thesis.pdf.
Pełny tekst źródłaStreszczenie:
The strategic requirement for naval submarines to operate in near surface and littoral
environments continues to increase as they are more frequently employed to support
joint force missions. The operational workload for helmsmen and the risk to mission
safety and success are significantly increased due to the interaction between the
submarine and the free-surface. This thesis reports on an experimental investigation
into the effects of submergence depth, speed of advance and length-to-diameter ratio
on the interaction between a streamlined axisymmetric body and the free-surface when
travelling in a near-surface condition.
A broad review of the existing literature indicates that little work has been published
to date on the effects of length-to-diameter on the near-surface performance of
streamlined axisymmetric bodies. Furthermore, there is little or no experimental data
available describing the vertical force and moment that act on a shallowly submerged
body moving beneath the free-surface. Nonetheless, there is evidence to confirm that
the requirement for submarine near-surface operation is significant and that a wellfounded
understanding of submarine near-surface performance is needed.
A model scale experimental program was conducted to measure and observe the
resistance, lift force, trimming moment and wave field generated by a series of
submerged bodies of revolution moving at constant forward speed. The Joubert
conventional submarine geometry was tested in its bare hull configuration in three
length-to-diameter ratio formats: 7.30, 8.50 and 9.50. The three geometries possess
the same maximum diameter. The models were tested at velocities that correspond to
a Froude number range of 0.10 to 0.50 inclusive and at centreline submergence depths
of between 1 and 3.5 hull diameters.
The results of the experiment indicate that the wave resistance, lift force and trimming
moment all vary periodically with speed and are directly influenced by the wavelength
of the free-surface wave field generated by the submerged body. The steady-state
wave field itself is a direct function of the submerged body’s length-to-diameter ratio
and speed of advance (Froude number). The magnitude of the forces and trimming
moment were found to diminish exponentially with an increase in submergence depth.
Considering the submergence depths and speeds experienced by naval submarines
when conducting near-surface operations, it is concluded that the effect of wave
resistance is a secondary issue and that the vertical lift force is of the greatest
operational significance. Based on the test results of the three Joubert hull geometries,
it was observed that for near-surface operation a larger length-to-diameter ratio is
preferable for achieving minimum resistance and vertical plane motion (lower relative
lift force and trimming moment).
An evaluation of the SHIPFLOW 4.7 potential flow software program was completed
using the experimentally measured data in conjunction with additional published
experimental and numerical wave resistance data. Good correlation was observed for
the predictions of lift force and trimming moment. Mixed results were achieved when
comparing the numerically predicted and experimentally measured wave resistance.
Nonetheless, it is concluded that the potential flow method offers an inexpensive and
suitable approach to evaluating the near-surface performance of submarine type
geometries.
Książki na temat "SUBMERGENCE DEPTH"
1
Wachsmann, Shelley. Deep-Submergence Archaeology. Redaktorzy Ben Ford, Donny L. Hamilton i Alexis Catsambis. Oxford University Press, 2012. http://dx.doi.org/10.1093/oxfordhb/9780199336005.013.0009.
Pełny tekst źródłaStreszczenie:
Coastal waters represent the greatest danger to ships and seafarers, as ships are most commonly lost at the intersection of water and shore. Ships sinking in deep water undergo a gradual transition. Deep-submergence archaeology refers to the archaeological study of cultural resources beyond the limits of traditional diving. The totality of archaeological exploration at great depths—discovering, recording, excavating, and recovering—requires function-specific tools. Deep Submergence Archaeological Excavations (DSAE) takes advantage of a remarkable existent toolkit, designed for a variety of oceanographic purposes other than the study of ancient shipwrecks. What is lacking at present is a comprehensive methodology for deepwater excavation. The ultimate goal of DSAE is to develop the technologies and the skills that permit expeditions to excavate and safely raise the contents and hull of an entire ship for conservation, study, and display.
2
Modell, Jerome H., i Sean Kiley. Pathophysiology and management of drowning. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199600830.003.0348.
Pełny tekst źródłaStreszczenie:
Drowning is a process beginning with airway submergence under a fluid medium, progressing to aspiration, and ultimately death in the absence of intervention. Aspiration of both fresh- and saltwater can cause pulmonary oedema, decreased compliance, intrapulmonary shunting, and severe hypoxia. Devastating neurological injury resulting from prolonged cerebral hypoxia is proportional to the duration of submersion and delay in effective resuscitation and oxygenation. Victims presenting to the emergency department awake and alert, or even stuporous, are likely to have a good neurological outcome with follow-up intensive care. Those presenting comatose are much more likely to have severe neurological deficits. Keys to survival are: timely rescue from the water, immediate initiation of aggressive supportive care regarding airway, cardiovascular and pulmonary function, and optimization of tissue oxygenation.
Części książek na temat "SUBMERGENCE DEPTH"
1
Anevlavi, D., i K. Belibassakis. "Effects on partially cavitating hydrofoils in finite submergence depth via an adjoint-based prediction method". W Sustainable Development and Innovations in Marine Technologies, 141–49. London: CRC Press, 2022. http://dx.doi.org/10.1201/9781003358961-19.
Pełny tekst źródła
2
Kumari, Nutan, i Arnab Chakraborty. "Effect of Submergence Depth on Tandem Hydrofoils at a Small Angle of Attack: A Hydrodynamic Analysis". W Lecture Notes in Mechanical Engineering, 407–13. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-6970-6_68.
Pełny tekst źródła
3
Jin, Kai, Surya P. Vanka, Brian G. Thomas i Xiaoming Ruan. "Large Eddy Simulations of the Effects of Double-Ruler Electromagnetic Braking and Nozzle Submergence Depth on Molten Steel Flow in A Commercial Continuous Casting Mold". W CFD Modeling and Simulation in Materials Processing 2016, 159–66. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2016. http://dx.doi.org/10.1002/9781119274681.ch20.
Pełny tekst źródła
4
Jin, Kai, Surya P. Vanka, Brian G. Thomas i Xiaoming Ruan. "Large Eddy Simulations of the Effects of Double-Ruler Electromagnetic Braking and Nozzle Submergence Depth on Molten Steel Flow in a Commercial Continuous Casting Mold". W The Minerals, Metals & Materials Series, 159–66. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-65133-0_20.
Pełny tekst źródła
5
Sharma, N., i H. Tiwari. "Experimental study on vertical velocity and submergence depth near Piano Key weir". W Labyrinth and Piano Key Weirs II, 93–100. CRC Press, 2013. http://dx.doi.org/10.1201/b15985-14.
Pełny tekst źródłaStreszczenia konferencji na temat "SUBMERGENCE DEPTH"
1
Liu, Tianshi, Yun Zhao i Yuhu Huang. "Research on the Submergence Depth Model of Oil Well Pumping". W 2021 6th International Conference on Intelligent Computing and Signal Processing (ICSP). IEEE, 2021. http://dx.doi.org/10.1109/icsp51882.2021.9408738.
Pełny tekst źródła
2
Wang, Xinxin, Fenfang Zhao, Yanli Tang, Liuyi Huang, Rong Wan i Hui Cheng. "Numerical Analysis of Submersible Mussel Raft for Exposed Marine Environment". W ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/omae2017-61682.
Pełny tekst źródłaStreszczenie:
To study the hydrodynamic characteristics of the submersible mussel raft in waves and currents, the numerical model of the submersible raft was established based on the finite element method and kinematics theory. The finite element program Aqua-FE™ was applied to simulate the impacts of waves and currents on the hydrodynamic responses of the surface and submerged rafts, respectively. Morison Equation was applied to compute the tension of the mooring lines. Apart from the wave condition, the flow has a significant effect on the mooring line tension of the submersible raft. The submerged raft is useful for reducing the mooring loads. The submergence depth of the mussel raft can be adjusted depending on the marine environment. The results show that the submerged raft wave response was found to be reduced relative to the surface raft. The vertical motion of mussel rope connection points was significantly reduced by submergence, resulting in reduced potential for mussel drop-off. Compared the performance of the submerged raft in the same condition, the motion amplitude of the framework of the raft decreased significantly while increasing the submergence depth. At the same period, the trend of the decrease followed by levelling off with an increasing wave height. However, the submergence depth had no significant effect on the mooring line tension.
3
Pernod, Laetitia, Matthieu Sacher, Jeroen Wackers, Benoit Augier i Patrick Bot. "Free-Surface Effects on Two-Dimensional Hydrofoils by RANS-VOF Simulations". W SNAME 24th Chesapeake Sailing Yacht Symposium. SNAME, 2022. http://dx.doi.org/10.5957/csys-2022-012.
Pełny tekst źródłaStreszczenie:
Foiling yachts and crafts are both very sensitive to the flying height in terms of stability and performance, raising the scientific issue of the influence of the free-surface when the foil is at low submergence. This work presents numerical simulations of a 2D hydrofoil section NACA0012 at 5° angle of attack in the vicinity of the free surface, for different values of the submergence depth, for a chord-based Froude number of 0.571 and a Reynolds number of 159,000. URANS equations are solved with a mixture model to capture the free surface, and using an automatic grid refinement. Verification of the numerical model and validation with data from the literature are presented. Deformation of the free surface and alteration of the hydrodynamic forces compared to the deep immersion case are observed for a submergence depth-to-chord ratio h/c lower than 2. The foil drag increases up to more than three times the infinite-depth value at h/c ≈ 0.5. The lift force slightly increases until h/c around 1, and then decreases sharply. For h/c < 0.5, the pressure field around the foil is totally modified and the lift is swapped to downward. The study highlights the importance of considering the effect of finite submergence to compute foils’ hydrodynamic forces, for example to be used in Velocity Prediction Programs (VPP) of foiling crafts.
4
Islam, Mohammed, Dong Cheol Seo i Wayne Raman-Nair. "Modelling and Analysis of Hydrodynamics of a Submerged Structure in Extreme Waves Using a SPH-Based Tool". W ASME 2021 40th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/omae2021-63034.
Pełny tekst źródłaStreszczenie:
Abstract The applications of a Smoothed Particle Hydrodynamics (SPH)-based, a Finite Volume Method (FVM)-based and a Boundary Element Method (BEM)-based tools to investigate the nonlinear interactions between large waves and a submerged horizontal circular structure and to some extent a rectangular cylinder at various submergence depths in deep water conditions are presented. The main aim is to validate the Lagrangian technique based SPH tool to predict the wave-structure interaction forces under large waves. The features of typical force curves in a wave cycle, the magnitude of wave forces, and the influence of relative axis depth of the structure in deep water conditions are investigated, primarily using an open-sourced SPH tool. Simulations were carried out in 2D with one deepwater wave at multiple submergence depths. The water surface elevations are predicted at different near- and far-field locations. The time-averaged mean and the average amplitude of the horizontal and vertical forces acting on the cylindrical model at various submergence depths are plotted and then physically interpreted. The wave forces and surface elevations are compared with the available published experimental studies and CFD (both FVM and BEM) predictions. Good agreement between the SPH predictions and the measurements was obtained for the submerged body’s surface elevation and hydrodynamic forces at all submergence depths. The FVM tends to overestimate the wave forces compared to the SPH predictions and the measurements, particularly for the shallowly submerged structure when extreme wave breaking occurs. The BEM predictions are reasonable for the non-wave breaking cases.
5
Raju, Rahul Dev, Madasamy Arockiasamy, Ranganathan Sundaravadivelu i Sherlin Prem Nishold Selvaraj. "Numerical Investigation on Wave Transmission by a Submerged Reef Using MIKE 3 WAVE FM". W ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-18499.
Pełny tekst źródłaStreszczenie:
Abstract Wave transmission of a 1:10 gradient slope submerged reef is studied using MIKE 3 WAVE FM software. The study focuses on the effect of wave steepness and relative submergence depth over the reef on the wave transmission for three water levels. The results from the numerical analysis are compared with published literature on wave transmission of submerged structures. The results from the numerical analysis using MIKE 3 WAVE FM software show that the wave steepness and relative submergence depth over the reef have strong dependence on the wave transmission of submerged reef. The wave transmission coefficient shows a decreasing trend with increasing wave steepness.
6
Barannyk, Oleksandr, Brad Buckham i Peter Oshkai. "Effect of Chordwise Flexibility and Depth of Submergence on an Oscillating Plate Underwater Propulsion System". W ASME 2010 3rd Joint US-European Fluids Engineering Summer Meeting collocated with 8th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2010. http://dx.doi.org/10.1115/fedsm-icnmm2010-30148.
Pełny tekst źródłaStreszczenie:
This work was dedicated to the experimental study of oscillating plate propulsors undergoing a combination of heave translation and pitch rotation. The oscillation kinematics are inspired by swimming mechanisms employed by fish and other marine animals. The primary focus was on the propulsive characteristics of such oscillating plates, which were studied by means of direct force measurements in the thrust-producing regime. Experiments were performed at constant Reynolds number and constant heave amplitude. By varying the Strouhal number, the depth of submergence and the chordwise flexibility of the plate, it was possible to investigate corresponding changes in the generated thrust and the hydromechanical efficiency. It was possible to establish a set of parameters, including the driving frequency of the system, the ratio of rigid to flexible segment length of the plate, and the range of Strouhal numbers that led to a peak efficiency of approximately 80%. The experiments involving plates with various ratios of rigid to flexible segment lengths showed that greater flexibility increased the propulsive efficiency and thrust compared to an identical motion of the purely rigid plate. By submerging the plate at different depths, it was observed that the proximity of the propulsor to the bottom of the channel led to overall increase in the thrust coefficient.
7
Jin, Chungkuk, WooChul Chung i Moo-Hyun Kim. "Effects of Submergence Depth of Submerged Floating Tunnel on Global Behaviors under Waves and Earthquakes". W OCEANS 2019 MTS/IEEE SEATTLE. IEEE, 2019. http://dx.doi.org/10.23919/oceans40490.2019.8962688.
Pełny tekst źródła
8
Wang, Yating, Yiyang Zhang, Zhu Fang i Xinxin Wu. "An Experimental Study on the Retention of Graphite Dust Aerosol in Pool Scrubbing and the Possible Application in HTGRs". W 2022 29th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/icone29-92561.
Pełny tekst źródłaStreszczenie:
Abstract Owing to the inherent safety, the modular high-temperature gas-cooled reactor (HTGR) eliminates the possibility of severe accidents in principle. Therefore, the source term is the main concern for HTGR accidents. Especially, the graphite dust problem, arising from the abrasion of fuel pebbles, complicates the evaluation of source terms. In the water ingress accidents, the graphite dust may be released to the containment during the overpressure discharge, which not only contributes to the source term but also makes trouble for post-accident measures. In this work, we consider the possibility to develop a pool scrubbing measure to retain graphite dust and fission products for the overpressure discharge of HTGR. A scrubber is set up with aerosol particle concentration measurement at both the inlet and outlet, which enables us to determine the decontamination factor (DF). By conducting a series of experiments for different submergence depth and particle size, it is demonstrated the DF value increases with the increase of submergence depth. When the submergence depth is 105 cm, the retention efficiency of graphite particles larger than 2 μm exceeds 96%. Our previous study has shown due to a fragmentation effect, most of the graphite particles released during the overpressure discharge are below 2 μm, while the DFs for these small particles fall below 20. The experimental results show that the pool scrubbing technology can efficiently retain the graphite particles for the overpressure discharge in HTRGs. More efforts are still needed to effectively improve the DF for graphite particles below 2 μm.
9
Satheesh, Sukruth, Clément Haëck i Francisco J. Huera-Huarte. "Effect of the Free Surface on the Drag Forces on a Flat Plate Translating Normal to the Flow". W ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-77646.
Pełny tekst źródłaStreszczenie:
A series of experiments were carried out with a flat plate towed normal to the flow in quiescent fluid. The focus was given to the analysis of the drag force seen by the plate as a function of its aspect ratio and hydraulic diameter. The effect of towing the plate near the water free surface was also investigated thoroughly. Plates of aspect ratio ranging from 0.25 to 4 were towed in a still water tank at different Reynolds numbers in the range from 15000 to 60000. Submergence depth was measured from the upper edge to the free surface and varied from zero to the centre of the tank. Forces on the plates were measured using a submersible bending beam load cell and the carriage motion was monitored by a rotary potentiometer. It was found that the drag increases abruptly prior subsiding with increasing submergence depth, with this effect being more dominant in lower aspect ratio plates. The abrupt rise in the drag is due to the interaction of the upper edge of the plate with the free surface resulting in a large shrinkage of the recirculation zone. The non-unit low aspect ratio plates also showed another drag peak around 50% depth, especially at lower speeds. Overall, the trends were Reynolds number independent, except when the aspect ratios was in the range from 0.75 to 1.33 and the plate was near the free surface.
10
Cho, Seok, Choon-Kyung Park, Hwan-Yeol Kim, Se-Young Chun, Chul-Hwa Song i Won-Pil Baek. "Air Clearing Oscillation Produced by APR1400 Prototype Sparger". W ASME 2002 Pressure Vessels and Piping Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/pvp2002-1125.
Pełny tekst źródłaStreszczenie:
KAERI has performed a series of experiments to investigate the performance of APR1400 prototype sparger in view of the dynamic load oscillation with the variation of test conditions such as discharged air mass, submergence of the sparger, valve opening time, and pool temperature during the air-clearing phase. The air mass and pool temperature are in the range of 0.8 ∼ 1.5 kg and 20 ∼ 90°C, respectively. The valve opening time can be adjusted in the range of 0.6 ∼ 1.7 sec according to the POSRV operating conditions. The maximum positive pressure amplitude, which is observed at the bottom of the quench tank, is increased with the submergence depth and maximum header pressure of sparger. The valve opening time has a considerable effect on the maximum amplitude. As the opening time decreases, the maximum amplitudes at the tank wall are increased. Air mass and pool temperature, however, have a weak effect on the maximum amplitude. Oscillation frequency is decreased with air mass in the range of 2.5 ∼ 4.5Hz.