scholarly journals Prototyping and Study of Mesh Turbomachinery Based on the Euler Turbine

Energies ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5292
Author(s):  
Yuri Appolonievich Sazonov ◽  
Mikhail Albertovich Mokhov ◽  
Inna Vladimirovna Gryaznova ◽  
Victoria Vasilievna Voronova ◽  
Vladimir Valentinovich Mulenko ◽  
...  
Keyword(s):  
Laboratory Tests ◽  
Pulse Mode ◽  
Scientific Development ◽  
Additive Technology ◽  
Liquid Motion ◽  
Curved Pipe ◽  
Curved Pipes ◽  
Flow Channels ◽  
Technical Potential ◽  
Study Results

This paper presents a scientific development aimed at improving the efficiency of turbomachines through the joint use of rotary-vane and vortex workflows. In the well-known Euler turbine, the rotor flow channels represent a set of curved pipes. The authors propose to consider in more detail the possibilities of using such rotating pipes in the implementation of an ejection (vortex) workflow. A hybrid pump was considered with the conclusion that its workflow can be described using two Euler equations. The results of computer simulation indicate that hybrid turbomachines are promising. The use of additive technology allowed the creation of micromodels of the Euler turbine with various rotor designs. Laboratory hydraulic tests showed that the liquid inlet to the rotor is possible in pulse mode. Laboratory tests of micromodels using compressed air showed that gas (or liquid) motion through curved pipes could be carried out from the rotor periphery to its center and then back, albeit through another curved pipe. The research results demonstrated that the scientific and technical potential of the Euler turbine is not yet fully unlocked, and research in this direction should continue. The study results are applicable in various industries including the energyeconomy, robotics, aviation, and water transport industries.

scholarly journals Numerical Investigation on Fluid Flow in a 90-Degree Curved Pipe with Large Curvature Ratio

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Yan Wang ◽  
Quanlin Dong ◽  
Pengfei Wang
Keyword(s):  
Fluid Flow ◽  
Internal Flow ◽  
Fluid Flows ◽  
Detached Eddy Simulation ◽  
Number Range ◽  
Curvature Ratio ◽  
Large Curvature ◽  
Curved Pipe ◽  
Eddy Simulation ◽  
Curved Pipes

In order to understand the mechanism of fluid flows in curved pipes, a large number of theoretical and experimental researches have been performed. As a critical parameter of curved pipe, the curvature ratioδhas received much attention, but most of the values ofδare very small (δ<0.1) or relatively small (δ≤0.5). As a preliminary study and simulation this research studied the fluid flow in a 90-degree curved pipe of large curvature ratio. The Detached Eddy Simulation (DES) turbulence model was employed to investigate the fluid flows at the Reynolds number range from 5000 to 20000. After validation of the numerical strategy, the pressure and velocity distribution, pressure drop, fluid flow, and secondary flow along the curved pipe were illustrated. The results show that the fluid flow in a curved pipe with large curvature ratio seems to be unlike that in a curved pipe with small curvature ratio. Large curvature ratio makes the internal flow more complicated; thus, the flow patterns, the separation region, and the oscillatory flow are different.

Mining Submersible Pump - Design, Characteristics and Protections

2014 ◽  
Vol 630 ◽  
pp. 99-108
Author(s):  
Andrzej Korczak ◽  
Grzegorz Peczkis ◽  
Tomasz Synowiec ◽  
Ievgenii Altyntsev
Keyword(s):  
Laboratory Tests ◽  
Security System ◽  
Numerical Calculations ◽  
Submersible Pump ◽  
Pump Design ◽  
Highly Efficient ◽  
Flow Channels ◽  
New Construction ◽  
Design Characteristics

This paper presents new construction of a submersible pump which is highly efficient due to the new solutions for flow channels. It includes the results of laboratory tests of the pump of the new construction. It also presents the results of numerical calculations of liquid’s movement in the flow channels of the pump, comparison of computing characteristics and characteristics measured in the laboratory.and an analysis of the essential parameters of the pump’s work which transgression could become a danger for the pump. In case of the danger the security system turns off the engine temporally or permanently.

Analogy between laminar flows in curved pipes and orthogonally rotating pipes

1994 ◽  
Vol 268 ◽  
pp. 133-145 ◽  
Author(s):  
Hiroshi Ishigaki
Keyword(s):  
Laminar Flows ◽  
Computational Studies ◽  
Flow Properties ◽  
Straight Pipe ◽  
Pipe Axis ◽  
Transfer Rates ◽  
Curved Pipe ◽  
Curved Pipes ◽  
Data Similarity ◽  
Friction Factors

The secondary flow of a viscous fluid, caused by the Coriolis force, through a straight pipe rotating about an axis perpendicular to the pipe axis is analogous to that of a fluid, caused by the centrifugal force, through a stationary curved pipe. The quantitative analogy between these two fully developed laminar flows will be demonstrated through similarity arguments, computational studies and the use of experimental data. Similarity considerations result in two analogous governing parameters for each flow, which include a new one for the rotating flow. When one of these analogous pairs of parameters of the two flows is large, it will be demonstrated that there are strong similarities between the two flows regarding friction factors, heat transfer rates, flow patterns and flow properties for the same values of the other pair of parameters.

scholarly journals California Community Pharmacist Preparedness in Ordering and Interpreting Laboratory Tests

2020 ◽  
Vol 67 (2) ◽  
pp. 33-37
Author(s):  
Angelica Del Rosario ◽  
Kathleen Feng ◽  
Lena Haddad ◽  
Brian Lee ◽  
Ryan Murakami ◽  
...  
Keyword(s):  
Laboratory Tests ◽  
Online Survey ◽  
Community Setting ◽  
Community Pharmacists ◽  
Self Report ◽  
Institutional Review Board ◽  
Survey Study ◽  
Institutional Review ◽  
Study Results ◽  
Descriptive Survey

Introduction The passage of Senate Bill 493 (SB 493) granted California pharmacists the ability to order and interpret lab tests without physician approval. Despite this legislation, not all pharmacists are aware of, or exercise, this authority. The goals of this study are to describe 1) pharmacists' willingness, 2) perceived factors influencing pharmacist preparedness, and 3) challenges and barriers to ordering laboratory tests in the community setting. Methods This is a prospective, descriptive survey study that was performed using online survey software from August 31, 2017, to October 4, 2017. An anonymous link was distributed to California pharmacists via California Society of Health-System Pharmacists (CSHP) and California Pharmacists Association (CPhA) email newsletters. Additionally, targeted interviews of pharmacists were conducted by phone to qualitatively assess barriers as well as successful practices. Institutional Review Board (IRB) approval was obtained prior to initiating the study. Results Sixty-six pharmacist respondents completed the online survey. The reported two biggest barriers to ordering lab tests identified by community pharmacists were 1) lack of available time and 2) compensation structure. Despite these barriers, most pharmacists were willing to order and interpret laboratory tests and accept the liability, regardless of a reimbursement guarantee. Conclusions Community pharmacists self-report preparedness to order and interpret laboratory tests. Barriers in carrying out this task include lack of staff, resources, compensation, and reimbursement structure.

scholarly journals Effect of Jatropha Sap (Jatropha curcas Linn.) on Incision Wound Healing in Female Mice (Mus musculus)

2021 ◽  
Vol 6 (5) ◽  
pp. 40-44
Author(s):  
Zahara Zahara ◽  
Muhammad Mirza ◽  
Rini Handayani ◽  
Harrizul Rivai
Keyword(s):  
Wound Healing ◽  
Mus Musculus ◽  
Jatropha Curcas ◽  
Laboratory Tests ◽  
Female Mice ◽  
Study Results ◽  
Digestive Disorders ◽  
Negative Controls ◽  
Incision Wound ◽  
Descriptive Method

Jatropha as a medicinal plant has been very widely used. Among them can cure rheumatic joints, tetanus, epilepsy, and bronchitis in children. Jatropha sap can be used as an antimicrobial, relieves wound bleeding, treats digestive disorders, and treats mouth sores and toothaches. Many people still use traditional medicine to treat wounds. One that is used to treat wounds is jatropha sap. This study aims to determine the effect of the incision wound healing in mice (Mus Musculus) by giving Jatropha sap (Jatropha curcas, Linn) seen from the disappearance of inflammation dryness wounds and the tightening of the skin. This study uses a descriptive method through laboratory tests. Based on the study results, it is known that Jatropha sap has the effect of healing incise wounds in female mice, seen from the elimination of inflammation, drying of the wounds to the closure of the skin (granulation) compared to negative controls.

Flow Visualization Experiments on Secondary Flow Patterns in an Isothermally Heated Curved Pipe

1987 ◽  
Vol 109 (1) ◽  
pp. 55-61 ◽  
Author(s):  
K. C. Cheng ◽  
F. P. Yuen
Keyword(s):  
Flow Visualization ◽  
Secondary Flow ◽  
Theoretical Models ◽  
Flow Patterns ◽  
Radius Of Curvature ◽  
Dean Number ◽  
Number Range ◽  
Curved Pipe ◽  
Curved Pipes ◽  
Numerical Predictions

Secondary flow patterns at the exit of a 180 deg bend (tube inside diameter d = 1.99 cm, radius of curvature Rc = 10.85 cm) are presented to illustrate the combined effects of centrifugal and buoyancy forces in hydrodynamically and thermally developing entrance region of an isothermally heated curved pipe with both parabolic and turbulent entrance velocity profiles. Three cases of upward, horizontal, and downward-curved pipe flows are studied for constant wall temperatures Tw=55–91°C, Dean number range K=22–1209 and ReRa=1.00×106–8.86×107. The flow visualization was realized by the smoke injection method. The secondary flow patterns shown are useful for future comparison with numerical predictions and confirming theoretical models. The results can be used to assess qualitatively the limit of the applicability of the existing correlation equations for laminar forced convection in isothermally heated curved pipes without buoyancy effects.

scholarly journals The Resonance Reliability and Global Sensitivity Analysis of Curved Pipe Conveying Fluid Based on TIS Method

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Zhao Yuzhen ◽  
Liu Yongshou ◽  
Guo Qing ◽  
Li Baohui
Keyword(s):  
Sensitivity Analysis ◽  
Natural Frequency ◽  
Global Sensitivity Analysis ◽  
Beam Theory ◽  
Reliability Estimation ◽  
Pipe Conveying Fluid ◽  
Curved Pipe ◽  
Global Sensitivity ◽  
Curved Pipes ◽  
Conveying Fluid

Based on the Flügge curved beam theory and total inextensible assumption, the dynamic equations of curved pipe’s in-plane vibration are established using the Newton method. The wave propagation method is proposed for calculating the natural frequency of curved pipes with clamped-clamped supported at both ends. Then, the performance function of the resonance reliability of curved pipe conveying fluid is established. Main and total effect indices of global sensitivity analysis (GSA) are introduced. The truncated importance sampling (TIS) method is used for calculating these indices. In the example, the natural frequency and critical velocity of a semicircular pipe are calculated. The importance ranking of input variables is obtained at different working conditions. The method proposed in this paper is valuable and leads to reliability estimation and antiresonance design of curved pipe conveying fluid.

Secondary Flow Velocity Field in Laminar Pulsating Flow Through Curved Pipes: PIV Measurements

2009 ◽  
Author(s):  
Mojtaba Jarrahi ◽  
Cathy Castelain ◽  
Hassan Peerhossaini
Keyword(s):  
Secondary Flow ◽  
Oscillation Period ◽  
Pulsating Flow ◽  
Transverse Strain ◽  
Piv Measurements ◽  
Curved Pipe ◽  
Transverse Mixing ◽  
Curved Pipes ◽  
Flow Through ◽  
Transverse Strains

Effects of different parameters on the secondary flow pattern have been studied experimentally by particle image velocimetry (PIV) for a developing laminar pulsating flow through a circular curved pipe. The curvature ratio is η = rc/r0 = 11 and the curvature angle is 90°. As different secondary flow patterns formed by oscillation cause different transverse mixings, the enhancement of transverse mixing is investigated here. A T-shaped structure installed downstream of the curved pipe allowed PIV measurements obviating light diffraction effects. From knowledge of the velocity components of the secondary flow, the variation in axial vorticity (ξ) and transverse strain (ε) were calculated. The experiments were carried out for the range of stationary Reynolds numbers 420≤Rest≤1000 (corresponding to Dean numbers 126.6≤Dn≤301.51), velocity component ratios 1≤(β = Umax,osc/Um,st)≤4 and frequency parameters 8.37&lt;(α = r0(ω/v)0.5)&lt;24.5. To guarantee being in the laminar regime, the higher values of β (β = 3 and 4) were studied just for Rest = 420. The effects of each parameter ((Rest, β and α) on transverse mixing are discussed by comparing the dimensionless vorticities (|ζP|/|ζS|) and dimensionless transverse strains (|εP|/|εS|) during a complete oscillation period.

Turbulent Flows in Curved Pipes: Recent Advances in Experiments and Simulations

2016 ◽  
Vol 68 (5) ◽  
Author(s):  
Athanasia Kalpakli Vester ◽  
Ramis Örlü ◽  
P. Henrik Alfredsson
Keyword(s):  
Turbulent Flows ◽  
Swirling Flow ◽  
Nuclear Reactors ◽  
Transition To Turbulence ◽  
Exhaust Gas ◽  
Gas Treatment ◽  
Curved Pipe ◽  
Pipe Flows ◽  
Curved Pipes ◽  
Essential Components

Curved pipes are essential components of nearly all the industrial process equipments, ranging from power production, chemical and food industries, heat exchangers, nuclear reactors, or exhaust gas ducts of engines. During the last two decades, an interest on turbulent flows in such conduits has revived, probably due to their connection to technical applications such as cooling systems of nuclear reactors (e.g., safety issues due to flow-induced fatigue) and reciprocating engines (e.g., efficiency optimization through exhaust gas treatment in pulsatile turbulent flows). The present review paper, therefore, is an account on the state-of-the-art research concerning turbulent flow in curved pipes, naturally covering mostly experimental work, while also analytical and numerical works are reviewed. This paper starts with a historical review on pipe flows in general and specifically on flows through curved conduits. In particular, research dealing with the effect of curvature on transition to turbulence, work dealing with pressure losses in curved pipes, as well as turbulence statistics are summarized. The swirl-switching phenomenon, a specific structural phenomenon occurring in turbulent curved pipe flows, which has interesting fundamental as well as practical implications, is reviewed. Additional complications, with respect to flow through bends, namely, entering swirling flow and pulsating flow, are reviewed as well. This review closes with a summary on the main literature body as well as an outlook on future work that should be performed in order to tackle open questions remaining in the field.

Laminar flow in a curved pipe with varying curvature

1976 ◽  
Vol 73 (4) ◽  
pp. 735-752 ◽  
Author(s):  
S. Murata ◽  
Y. Miyake ◽  
T. Inaba
Keyword(s):  
Reynolds Number ◽  
Flow Direction ◽  
Circular Cross Section ◽  
Outer Side ◽  
Large Reynolds Number ◽  
Phase Lag ◽  
Mean Flow ◽  
Curved Pipe ◽  
Curved Pipes ◽  
Centre Line

The steady laminar motion of fluid through pipes of circular cross-section, the curvature of whose centre-line varies locally, is analysed theoretically. The flow in three kinds of pipes whose centre-lines are specified by \[ \hat{y} = a(1+\kappa^2\hat{x}^2)^{\frac{1}{2}},\quad\hat{y} = a\tan h\kappa\hat{x}\quad{\rm and}\quad\hat{y} = a\sin\kappa\hat{x} \] are treated as the examples of once-, twice- and periodically-curved pipes, respectively. The analysis is valid for any other two-dimensionally curved pipes, when centre-line curvature is small. At very small Reynolds number, the position of maximum axial velocity shifts towards the inner side of the pipe section; at large Reynolds number, on the contrary, it tends to the outer side, owing to centrifugal force. Furthermore, in the latter case, adaptation of the flow follows the change of mean-flow direction, with a phase lag.

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