Fan Rotor Flow Measurements in a Turbofan Engine Operating with Inlet Swirl Distortion

2017 ◽  
Author(s):  
Dustin J. Frohnapfel ◽  
Walter F. O'Brien ◽  
Kevin T. Lowe
Keyword(s):  
Flow Measurements ◽  
Turbofan Engine ◽  
Inlet Swirl ◽  
Rotor Flow

On the Application of Particle Image Velocimetry for Turbofan Engine Flow Quantification

2019 ◽  
Author(s):  
Dillon P. Sluss ◽  
William M. George ◽  
K. Todd Lowe
Keyword(s):  
Particle Image Velocimetry ◽  
Risk Reduction ◽  
Case Studies ◽  
Particle Image ◽  
Flow Quantification ◽  
Endoscopic Imaging ◽  
Flow Measurements ◽  
Turbofan Engine ◽  
Imaging Methods ◽  
Image Velocimetry

Abstract Given the robustness and maturity of contemporary particle image velocimetry (PIV) methods, detailed flow measurements are now possible in actual turbine engine environments. For instance, flow non-uniformity measurements are possible in fan outlet gas-paths by adapting PIV hardware to the restricted access afforded in such applications. In the present work, a framework is proposed and demonstrated for planning and executing stereoscopic PIV measurements in the fan outlet duct of a Pratt & Whitney Canada JT15D-1A research turbofan engine. Two case studies have been carried out by following this framework in order to demonstrate two different imaging methods — conventional lens/camera coupling and endoscopic imaging. A key step within the planning and execution framework is risk reduction, and this step resulted in considerable refinement of the methods in both cases. For instance, in endoscopic imaging, the risk reduction provided a new fluorescent paint application for obtaining near wall data not previously possible. The data obtained in the engine experiments have been used to quantify the uncertainty for both imaging methods, not surprisingly revealing 50% greater average uncertainties for endoscopic PIV versus conventional lens/camera imaging. The results from the case studies indicate that both imaging methods may be practically and economically implemented for detailed measurements in fan outlet ducts, and application demands may be carefully considered, and risks reduced, using the framework proposed.

Influence of Inlet Swirl on the Aerodynamics of a Model Turbofan Lobed Mixer

2010 ◽  
Author(s):  
Zhijun Lei ◽  
Ali Mahallati ◽  
Mark Cunningham ◽  
Patrick Germain
Keyword(s):  
Swirling Flow ◽  
Velocity Ratio ◽  
Core Region ◽  
Streamwise Vortices ◽  
Reversed Flow ◽  
Flow Measurements ◽  
Core Flow ◽  
The Core ◽  
Exit Nozzle ◽  
Inlet Swirl

This paper presents a detailed experimental investigation of the influence of core flow inlet swirl on the mixing and performance of a 12-lobe un-scalloped turbofan mixer. Measurements were made downstream of the mixer in a co-annular wind tunnel. The core-to-bypass velocity ratio was set to 2:1, temperature ratio to 1.0, and pressure ratio to 1.03, giving a Reynolds number of 5.2×105, based on the core flow inlet velocity and equivalent hydraulic diameter. In the core flow, the background turbulence intensity was raised to 5% and the swirl angle was varied using five vane geometries, with nominally uniform swirl angles of 0°, 5°, 10°, 20° and 30°. Flow measurements captured flow structures involved in the mixing process. Most of mixing took place immediately downstream of the exit nozzle. The vane wake slightly enhanced large scale mixing of streamwise vortices. At low swirl angles, mixing was found to be mainly due to the interaction between streamwise vortices and normal vortices. At high swirl angles, the lobed mixer acted similar to a guide vane and removed most of the inlet swirl between the crest and trough of the mixer. However, the upstream swirling flow persisted in the core region between the center-body and lobed mixer trough, causing a reverse flow zone downstream of the centre-body. As the reversed flow became larger with increasing swirl, the swirling flow in the core region moved radially outwards and further interacted with the outer region flow. The stronger interaction of streamwise vortices with normal vortex improved mixing from the trough to the crest of the lobed mixer. The balance between enhanced mixing and increased reversed flow downstream of the centre-body, resulted in increased overall total pressure losses with increasing inlet swirl angles.

Clinical and Experimental Analysis of 201Thallium Uptake of the Heart

1978 ◽  
Vol 17 (04) ◽  
pp. 142-148
Author(s):  
U. Büll ◽  
S. Bürger ◽  
B. E. Strauer
Keyword(s):  
Oxygen Consumption ◽  
Left Ventricle ◽  
Muscle Mass ◽  
Myocardial Oxygen Consumption ◽  
Animal Experiments ◽  
Left Ventricular ◽  
Left Ventricular Wall ◽  
Ventricular Wall ◽  
Flow Measurements ◽  
Myocardial Flow

Studies were carried out in order to determine the factors influencing myocardial 201T1 uptake. A total of 158 patients was examined with regard to both 201T1 uptake and the assessment of left ventricular and coronary function (e. g. quantitative ventriculography, coronary arteriography, coronary blood flow measurements). Moreover, 42 animal experiments (closed chest cat) were performed. The results demonstrate that:1) 201T1 uptake in the normal and hypertrophied human heart is linearly correlated with the muscle mass of the left ventricle (LVMM);2) 201T1 uptake is enhanced in the inner (subendocardial) layer and is decreased in the outer (subepicardial) layer of the left ventricular wall. The 201T1 uptake of the right ventricle is 40% lower in comparison to the left ventricle;3) the basic correlation between 201T1 uptake and LVMM is influenced by alterations of both myocardial flow and myocardial oxygen consumption; and4) inotropic interventions (isoproterenol, calcium, norepinephrine) as well as coronary dilatation (dipyridamole) may considerably augment 201T1 uptake in accordance with changes in myocardial oxygen consumption and/or myocardial flow.It is concluded that myocardial 201T1 uptake is determined by multiple factors. The major determinants have been shown to include (i) muscle mass, (ii) myocardial flow and (iii) myocardial oxygen consumption. The clinical data obtained from patient groups with normal ventricular function, with coronary artery disease, with left ventricular wall motion abnormalities and with different degree of left ventricular hypertrophy are correlated with quantitated myocardial 201T1 uptake.

Partition Coefficient of 133Xe between Blood and Eye Tissues

1975 ◽  
Vol 14 (04) ◽  
pp. 301-309
Author(s):  
A. Marczak ◽  
A. Moszczyńska-Kowalska ◽  
H. Kowalski
Keyword(s):  
Partition Coefficient ◽  
Aqueous Humour ◽  
Vitreous Body ◽  
Flow Measurements ◽  
Solubility Coefficient ◽  
Eye Muscles ◽  
Eye Tissues ◽  
Relative Solubility ◽  
Blood Flow Measurements

SummaryThe relative solubility coefficient of 133Xe and the tissue-blood partition coefficient for the aqueous humour vitreous body, conjunctiva and external eye muscles of the rabbit were determined in vitro at 37° C and at various haematocrit values. The partition coefficient for haematocrit 40 was: for the aqueous humour 0,49 ml/ml, for the vitreous body 0,50 ml/ml, for the conjunctiva 0,81 ml/g and for the external eye muscles 0,77 ml/g. It was found that the solubility of 133Xe in rabbit erythrocytes is about 50 per cent higher than that in human red cells. The consequences of this fact for the precision of blood flow measurements by the method of tissue clearance are discussed.

Investigation of the influence of the flow structure on the accuracy of flow measurement before a hydrometric structure in an open channel

2020 ◽  
pp. 41-44
Author(s):  
Anatoly Kusher
Keyword(s):  
Velocity Profile ◽  
Flow Velocity ◽  
Water Flow ◽  
Flow Measurement ◽  
Water Discharge ◽  
Critical Depth ◽  
Flow Measurements ◽  
Study Results ◽  
Flow Velocity Profile ◽  
Upstream Flow

The reliability of water flow measurement in irrigational canals depends on the measurement method and design features of the flow-measuring structure and the upstream flow velocity profile. The flow velocity profile is a function of the channel geometry and wall roughness. The article presents the study results of the influence of the upstream flow velocity profile on the discharge measurement accuracy. For this, the physical and numerical modeling of two structures was carried out: a critical depth flume and a hydrometric overfall in a rectangular channel. According to the data of numerical simulation of the critical depth flume with a uniform and parabolic (1/7) velocity profile in the upstream channel, the values of water discharge differ very little from the experimental values in the laboratory model with a similar geometry (δ < 2 %). In contrast to the critical depth flume, a change in the velocity profile only due to an increase in the height of the bottom roughness by 3 mm causes a decrease of the overfall discharge coefficient by 4…5 %. According to the results of the numerical and physical modeling, it was found that an increase of backwater by hydrometric structure reduces the influence of the upstream flow velocity profile and increases the reliability of water flow measurements.

Pressure-Flow Measurements for Selected Oral and Nasal Sound Segments Produced by Normal Adults

1992 ◽  
Vol 29 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Meri L. Andreassen ◽  
Bonnie E. Smith ◽  
Thomas W. Guyette
Keyword(s):  
Limited Information ◽  
Flow Data ◽  
Female Adult ◽  
Flow Measurements ◽  
Pressure Flow ◽  
Orifice Area ◽  
Normative Pressure ◽  
Categorization Scheme ◽  
Velopharyngeal Function ◽  
Normal Adults

Pressure-flow data are often used to provide information about the adequacy of velopharyngeal valving for speech. However, there is limited information available concerning simultaneous pressure-flow measurements for oral and nasal sound segments produced by normal speakers. This study provides normative pressure, flow, and velopharyngeal orifice area measurements for selected oral and nasal sound segments produced by 10 male and 10 female adult speakers. An aerodynamic categorization scheme of velopharyngeal function, including one typical category and three atypical categories (open, closed, and mixed) is proposed.

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