scholarly journals Chaos and the Flow Capture Problem: Polluting is Easy, Cleaning is Hard

2018 ◽  
Vol 10 (3) ◽  
Author(s):  
Lachlan D. Smith ◽  
Guy Metcalfe ◽  
Julio M. Ottino
Keyword(s):  
Flow Capture

Corridor-based metro network design with travel flow capture

2018 ◽  
Vol 89 ◽  
pp. 58-67 ◽  
Author(s):  
Gabriel Gutiérrez-Jarpa ◽  
Gilbert Laporte ◽  
Vladimir Marianov
Keyword(s):  
Network Design ◽  
Flow Capture ◽  
Metro Network

Modeling the In-Flow Capture of Magnetic Nanoparticles

2019 ◽  
pp. 151-171
Author(s):  
Bart Hallmark ◽  
Nicholas J. Darton ◽  
Daniel Pearce
Keyword(s):  
Magnetic Nanoparticles ◽  
Flow Capture

scholarly journals Electroosmotic flow driven microfluidic device for bacteria isolation using magnetic microbeads

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Samuel Miller ◽  
Alison A. Weiss ◽  
William R. Heineman ◽  
Rupak K. Banerjee
Keyword(s):  
Microfluidic Device ◽  
Electroosmotic Flow ◽  
Point Of Care ◽  
Food Poisoning ◽  
Fluorescent Intensity ◽  
Magnetic Microbeads ◽  
E Coli ◽  
Detection Assay ◽  
Flow Capture ◽  
Improved Performance

Abstract The presence of bacterial pathogens in water can lead to severe complications such as infection and food poisoning. This research proposes a point-of-care electroosmotic flow driven microfluidic device for rapid isolation and detection of E. coli in buffered solution (phosphate buffered saline solution). Fluorescent E. coli bound to magnetic microbeads were driven through the microfluidic device using both constant forward flow and periodic flow switching at concentrations ranging from 2 × 105 to 4 × 107 bacteria/mL. A calibration curve of fluorescent intensity as a function of bacteria concentration was created using both constant and switching flow, showing an increase in captured fluorescent pixel count as concentration increases. In addition, the use of the flow switching resulted in a significant increase in the capture efficiency of E. coli, with capture efficiencies up to 83% ± 8% as compared to the constant flow capture efficiencies (up to 39% ± 11%), with a sample size of 3 µL. These results demonstrate the improved performance associated with the use of the electroosmotic flow switching system in a point-of-care bacterial detection assay.

The in-flow capture of superparamagnetic nanoparticles for targeting therapeutics

2008 ◽  
Vol 4 (1) ◽  
pp. 19-29 ◽  
Author(s):  
Nicholas J. Darton ◽  
Bart Hallmark ◽  
Xuan Han ◽  
Sarah Palit ◽  
Nigel K.H. Slater ◽  
...  
Keyword(s):  
Superparamagnetic Nanoparticles ◽  
Flow Capture

The In-flow Capture of Superparamagnetic Nanoparticles for Targeting of Gene Therapeutics

2008 ◽  
Author(s):  
N. J. Darton ◽  
B. Hallmark ◽  
X. Han ◽  
S. Palit ◽  
M. R. Mackley ◽  
...  
Keyword(s):  
Superparamagnetic Nanoparticles ◽  
Flow Capture

scholarly journals Framework for estimation of nacelle drag on isolated aero-engines with separate jets

2020 ◽  
Vol 234 (14) ◽  
pp. 2025-2040
Author(s):  
Santiago Ramirez-Rubio ◽  
David G MacManus
Keyword(s):  
Mach Number ◽  
Near Field ◽  
Angle Of Attack ◽  
Field Method ◽  
Main Body ◽  
Reduced Order Models ◽  
Reduced Order ◽  
Flow Capture ◽  
Aero Engines ◽  
Engine Size

Typically, the evaluation of nacelle drag in preliminary design is required to find an overall optimum engine cycle and flight trajectory. This work focuses on the drag characteristics of aero-engine nacelles with separate jet exhausts. The main body of analysis comes from 3D numerical simulations. A new near-field method to compute the post-exit force of a nacelle is presented and evaluated. The effects of the engine size, Mach number, mass flow capture ratio and angle of attack are assessed. The results obtained from the numerical assessments were used to evaluate conventional reduced-order models for the estimation of nacelle drag. Within this context, the effect of the engine size is typically estimated by the scaling ratio between the maximum areas and Reynolds numbers. The effect of the angle of attack on nacelle drag is mostly a function of the nacelle geometry and angle of attack. In general, typical low-order models based on skin friction and form factor can underestimate the friction drag by up to 15% at cruise operating point. Similarly, reduced-order models based solely on Reynolds number, and Mach number can underestimate the overall nacelle drag by up to 74% for free stream Mach number larger than the drag rise Mach number.

Permuted proper orthogonal decomposition for analysis of advecting structures

2021 ◽  
Vol 930 ◽  
Author(s):  
Hanna M. Ek ◽  
Vedanth Nair ◽  
Christopher M. Douglas ◽  
Timothy C. Lieuwen ◽  
Benjamin L. Emerson
Keyword(s):  
Proper Orthogonal Decomposition ◽  
Convergence Rates ◽  
Separation Of Variables ◽  
Cross Flow ◽  
Orthogonal Decomposition ◽  
Inner Product ◽  
Turbulent Shear ◽  
Jet In Cross Flow ◽  
Flow Capture ◽  
Proper Orthogonal

Flow data are often decomposed using proper orthogonal decomposition (POD) of the space–time separated form, $\boldsymbol {q}'\left (\boldsymbol {x},t\right )=\sum _j a_j\left (t\right )\boldsymbol {\phi }_j\left (\boldsymbol {x}\right )$ , which targets spatially correlated flow structures in an optimal manner. This paper analyses permuted POD (PPOD), which decomposes data as $\boldsymbol {q}'\left (\boldsymbol {x},t\right )=\sum _j a_j\left (\boldsymbol {n}\right )\boldsymbol {\phi }_j\left (s,t\right )$ , where $\boldsymbol {x}=(s,\boldsymbol {n})$ is a general spatial coordinate system, $s$ is the coordinate along the bulk advection direction and $\boldsymbol {n}=(n_1,n_2)$ are along mutually orthogonal directions normal to the advection characteristic. This separation of variables is associated with a fundamentally different inner product space for which PPOD is optimal and targets correlations in $s,t$ space. This paper presents mathematical features of PPOD, followed by analysis of three experimental datasets from high-Reynolds-number, turbulent shear flows: a wake, a swirling annular jet and a jet in cross-flow. In the wake and swirling jet cases, the leading PPOD and space-only POD modes focus on similar features but differ in convergence rates and fidelity in capturing spatial and temporal information. In contrast, the leading PPOD and space-only POD modes for the jet in cross-flow capture completely different features – advecting shear layer structures and flapping of the jet column, respectively. This example demonstrates how the different inner product spaces, which order the PPOD and space-only POD modes according to different measures of variance, provide unique ‘lenses’ into features of advection-dominated flows, allowing complementary insights.

scholarly journals Aerodynamics of aero-engine installation

2016 ◽  
Vol 230 (14) ◽  
pp. 2673-2692 ◽  
Author(s):  
Tomasz P Stańkowski ◽  
David G MacManus ◽  
Christopher TJ Sheaf ◽  
Robert Christie
Keyword(s):  
Lift Coefficient ◽  
Aerodynamic Characteristics ◽  
Installation Effects ◽  
Through Flow ◽  
Aero Engine ◽  
Flow Capture ◽  
Research Programmes ◽  
Drag And Lift ◽  
Drag And Lift Coefficient ◽  
Aircraft Aerodynamics

This paper describes current progress in the development of methods to assess aero-engine airframe installation effects. The aerodynamic characteristics of isolated intakes, a typical transonic transport aircraft as well as a combination of a through-flow nacelle and aircraft configuration have been evaluated. The validation task for an isolated engine nacelle is carried out with concern for the accuracy in the assessment of intake performance descriptors such as mass flow capture ratio and drag rise Mach number. The necessary mesh and modelling requirements to simulate the nacelle aerodynamics are determined. Furthermore, the validation of the numerical model for the aircraft is performed as an extension of work that has been carried out under previous drag prediction research programmes. The validation of the aircraft model has been extended to include the geometry with through flow nacelles. Finally, the assessment of the mutual impact of the through flow nacelle and aircraft aerodynamics was performed. The drag and lift coefficient breakdown has been presented in order to identify the component sources of the drag associated with the engine installation. The paper concludes with an assessment of installation drag for through-flow nacelles and the determination of aerodynamic interference between the nacelle and the aircraft.

Performance of a jaws inlet under off-design conditions

2016 ◽  
Vol 231 (2) ◽  
pp. 294-305 ◽  
Author(s):  
Tianlai Gu ◽  
Shuai Zhang ◽  
Yao Zheng
Keyword(s):  
Mach Number ◽  
Flow Fields ◽  
Back Pressure ◽  
Low Mach Number ◽  
Mass Capture ◽  
Constant Area ◽  
Flow Capture ◽  
Mach Numbers ◽  
High Mach ◽  
Better Than

Numerical analysis was conducted of a jaws inlet under different working conditions, including angles of attack of 0° and 3°, varying Mach number, and varying back pressure with a constant-area isolator, to investigate its performance and flow fields of starting and unstarting states. Results reveal that the jaws inlet has an enhanced flow capture capability in starting states, with the mass capture ratio higher than 0.96, but relatively reduced working range of inflow Mach numbers. Its performance at a low Mach number is better than that at a high Mach number. Non-uniform flow fields are observed in unstarting cases at low Mach numbers and high back pressures, while separation structures are confined in the pitching compression section. Further increase in Mach number or decrease in back pressure does not result in significant changes in the separation structures. In the unstarting case under a high back pressure, it is hard to achieve restarting through reductions in the back pressure.

Sign in / Sign up

Export Citation Format

Share Document