The Impact of Pitot Tube Size on Velocity Field in a Closed Return Wind Tunnel

ABSTRACTWe examine how stress has the potential to shape the character of the electron transport that occurs within ZnO. In order to narrow the scope of this analysis, we focus on a determination of the velocity-field characteristics associated with bulk wurtzite ZnO. Monte Carlo simulations of the electron transport are pursued for the purposes of this analysis. Rather than focusing on the impact of stress in of itself, instead we focus on the changes that occur to the energy gap through the application of stress, i.e., energy gap variations provide a proxy for the amount of stress. Our results demonstrate that stress plays a significant role in shaping the form of the velocity-field characteristics associated with ZnO. This dependence could potentially be exploited for device application purposes.

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Influence of rotating magnetic field on Maxwell saturated ferrofluid flow over a heated stretching sheet with heat generation/absorption

Mechanics & Industry ◽

10.1051/meca/2019022 ◽

2019 ◽

Vol 20 (5) ◽

pp. 502 ◽

Cited By ~ 3

Author(s):

Aaqib Majeed ◽

Ahmed Zeeshan ◽

Farzan Majeed Noori ◽

Usman Masud

Keyword(s):

Magnetic Field ◽

Temperature Field ◽

Velocity Field ◽

Differential Equations ◽

Heat Transport ◽

Viscous Dissipation ◽

Heat Generation ◽

Fluid Motion ◽

Numerical Procedure ◽

The Impact

This article is focused on Maxwell ferromagnetic fluid and heat transport characteristics under the impact of magnetic field generated due to dipole field. The viscous dissipation and heat generation/absorption are also taken into account. Flow here is instigated by linearly stretchable surface, which is assumed to be permeable. Also description of magneto-thermo-mechanical (ferrohydrodynamic) interaction elaborates the fluid motion as compared to hydrodynamic case. Problem is modeled using continuity, momentum and heat transport equation. To implement the numerical procedure, firstly we transform the partial differential equations (PDEs) into ordinary differential equations (ODEs) by applying similarity approach, secondly resulting boundary value problem (BVP) is transformed into an initial value problem (IVP). Then resulting set of non-linear differentials equations is solved computationally with the aid of Runge–Kutta scheme with shooting algorithm using MATLAB. The flow situation is carried out by considering the influence of pertinent parameters namely ferro-hydrodynamic interaction parameter, Maxwell parameter, suction/injection and viscous dissipation on flow velocity field, temperature field, friction factor and heat transfer rate are deliberated via graphs. The present numerical values are associated with those available previously in the open literature for Newtonian fluid case (γ 1 = 0) to check the validity of the solution. It is inferred that interaction of magneto-thermo-mechanical is to slow down the fluid motion. We also witnessed that by considering the Maxwell and ferrohydrodynamic parameter there is decrement in velocity field whereas opposite behavior is noted for temperature field.

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573 THE IMPACT OF NEPHROSTOMY TUBE SIZE ON POST OPERATIVE PAIN AND PERINEPHRIC COLLECTION AFTER PERCUTANEOUS NEPHROLITHOTOMY. A RANDOMIZED CONTROLLED TRIAL

European Urology Supplements ◽

10.1016/s1569-9056(09)60568-6 ◽

2009 ◽

Vol 8 (4) ◽

pp. 264

Author(s):

K. Alam ◽

R. Biyabani ◽

M.H. Ather

Keyword(s):

Randomized Controlled Trial ◽

Percutaneous Nephrolithotomy ◽

Controlled Trial ◽

Nephrostomy Tube ◽

Tube Size ◽

Randomized Controlled ◽

Post Operative Pain ◽

The Impact

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Effect of an Axially Tilted Variable Stator Vane Platform on Penny Cavity and Main Flow

10.1115/gt2021-59182 ◽

2021 ◽

Author(s):

Johannes Janssen ◽

Daniel Pohl ◽

Peter Jeschke ◽

Alexander Halcoussis ◽

Rainer Hain ◽

...

Keyword(s):

Wind Tunnel ◽

Flow Region ◽

Cavity Flow ◽

Main Flow ◽

Pressure Probe ◽

Stator Vane ◽

Cfd Analyses ◽

Annular Cascade ◽

The Impact ◽

Variable Stator

Abstract This paper presents the impact of an axially tilted variable stator vane platform on penny cavity flow and passage flow, with the aid of both optical and pneumatic measurements in an annular cascade wind tunnel as well as steady CFD analyses. Variable stator vanes (VSVs) in axial compressors require a clearance from the endwalls. This means that penny cavities around the vane platform are inevitable. Production and assembly deviations can result in a vane platform which is tilted about the circumferential axis. Due to this deformation, backward facing steps occur on the platform edge. Penny cavity and main flow in geometries with and without platform tilting were compared in an annular cascade wind tunnel, which comprises a single row of 30 VSVs. Detailed particle image velocimetry (PIV) measurements were conducted inside the penny cavity and in the vane passage. Steady pressure and velocity data was obtained by two-dimensional multi-hole pressure probe traverses in the inflow and the outflow. Furthermore, pneumatic measurements were carried out using pressure taps inside the penny cavity. Additionally, oil flow visualization was conducted on the airfoil, hub, and penny cavity surfaces. Steady CFD simulations with boundary conditions, according to the measurements, have been benchmarked against experimental data. The results show that tilting the VSV platform reduces the mass flow into and out of the penny cavity. By decreasing penny cavity leakage, platform tilting also affects the passage flow where it leads to a reduced turbulence level and total pressure loss in the leakage flow region. In summary, the paper demonstrates the influence of penny platform tilting on cavity flow and passage flow and provides new insights into the mechanisms of penny cavity-associated losses.

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Impact of nasogastric decompression on gastric tube size after McKeown minimally invasive esophagectomy: A retrospective controlled cohort study

10.21203/rs.3.rs-1013418/v1 ◽

2021 ◽

Author(s):

Duo Jiang ◽

Xian-Ben Liu ◽

Wen-Qun Xing ◽

Pei-Nan Chen ◽

Shao-Kang Feng ◽

...

Keyword(s):

Minimally Invasive ◽

Gastric Tube ◽

Enhanced Recovery ◽

Minimally Invasive Esophagectomy ◽

Tube Size ◽

Invasive Esophagectomy ◽

Chest X Ray ◽

The Right ◽

The Impact ◽

Nasogastric Decompression

Abstract Purpose: This retrospective study evaluated the impact of nasogastric decompression (NGD) on gastric tube size to optimize the Enhanced Recovery After Surgery protocol after McKeown minimally invasive esophagectomy (MIE). Methods: Overall, 640 patients were divided into two groups according to nasogastric tube (NGT) placement intraoperatively. Using propensity score matching, 203 pairs of individuals were identified for gastric tube size comparisons on postoperative days (PODs) 1 and 5. Results: Gastric tubes were larger in the non-NGD group than the NGD group on POD 1 (vertical distance from the right edge of the gastric tube to the right edge of the thoracic vertebra, 22.2 [0–34.7] vs. 0 [0–22.5] mm, p <0.001). No difference was noted between the groups on POD 5 (18.5 [0–31.7] vs. 18.0 [0–25.4] mm, p =0.070). Univariate and multivariate analyses showed that non-NGD was an independent risk factor for gastric tube distention on POD 1. No difference in the incidence of complications (Clavien–Dindo（CD）≥2) (40 (23.0%) vs. 46 (19,8%), p =0.440), pneumonia (CD≥2) (29 [16.8%] vs. 30 [12.9%], p =0.280) or anastomotic leakage (CD≥3) (3 [1.7%] vs. 6 [2.6%], p =0.738) were noted between the without gastric tube distention group and with gastric tube distention group. Conclusion: Intraoperative NGT placement reduces gastric tube distention rates after McKeown MIE on POD 1, but the complications are similar to those of unconventional NGT placement. This finding is based on NGT placement or replacement at the appropriate time postoperatively through bedside chest X-ray examination.

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Photogrammetric Investigation of the Flying Shape of Spinnakers in a Twisted Flow Wind Tunnel

10.5957/csys-2009-008 ◽

2009 ◽

Author(s):

Kai Graf ◽

Olaf Müller

Keyword(s):

Image Processing ◽

Pattern Recognition ◽

High Resolution ◽

Wind Tunnel ◽

Wind Velocity ◽

Digital Cameras ◽

Pattern Recognition Methods ◽

Twisted Flow ◽

High Resolution Images ◽

The Impact

This paper describes a method for the acquisition of the flying shape of spinnakers in a twisted flow wind tunnel. The method is based on photogrammetry. A set of digital cameras is used to obtain high resolution images of the spinnaker from different viewing angles. The images are post-processed using image-processing tools, pattern recognition methods and finally the photogrammetry algorithm. Results are shown comparing design versus flying shape of the spinnaker and the impact of wind velocity and wind twist on the flying shape. Finally some common rules for optimum spinnaker trimming are investigated and examined.

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Environmental Assessment of Xinhe Beach Development

Materials Science Forum ◽

10.4028/www.scientific.net/msf.980.459 ◽

2020 ◽

Vol 980 ◽

pp. 459-468

Author(s):

Zhi Lin Sun ◽

Ju Yuan Luo ◽

Weng Ang Xiang ◽

Yu Meng Gong

Keyword(s):

Velocity Field ◽

Water Level ◽

Wave Height ◽

Ecological Environment ◽

Environmental Damage ◽

Height Distribution ◽

Astronomical Tide ◽

Effective Wave ◽

Hydrodynamic Environment ◽

The Impact

The proliferation of beach renovation is affecting the change of the landform of the coast and threatening the ecological environment. Therefore, it is necessary to assess the impact on the environment after the beach is transformed. The survey area is located near the Shipu fishing port in the south of Ningbo City, Zhejiang Province. Based on the Delft-3D grid nesting model and wave-fluid coupling model, the astronomical tide and hydrodynamic environment of the 30 days before the construction were simulated. After the beach was rebuilt and sand was added and the spur dike was added, the astronomical tide and hydrodynamic environment were again simulated. Finally, based on the simulated data, the water level, velocity field, effective wave height distribution, and siltation and siltation of Xinhe Beach were obtained. Xinhe Beach's environmental damage risk indicators can be evaluated based on water level, velocity field, effective wave height direction and sediment erosion and deposition. Artificial sanding and construction of spur dikes will change the hydrodynamics and scouring and siltation of Xinhe Beach, but have little effect on the coastal terrain and ecological environment.

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