Choking and Mixing of Two Compressible Fluid Streams

1976 ◽  
Vol 98 (2) ◽  
pp. 311-317 ◽  
Author(s):  
D. R. Otis
Keyword(s):  
Compressible Fluid ◽  
Ideal Gas ◽  
Gas Analysis ◽  
Mixing Process ◽  
Mixed States ◽  
Mixed Flow ◽  
One Dimensional ◽  
Process Solution ◽  
Forbidden Region ◽  
The Relationship

The mixing of a supersonic with a subsonic stream is treated in a one-dimensional, ideal gas analysis to determine when the mixed flow can be supersonic and to reveal the relationship between certain phenomena described by the terms “forbidden region” of “thermal choking.” A singularity in the equations is shown to divide the mixing process solution curves into two branches: subcritical or supercritical leading, respectively, to subsonic or supersonic mixed states.

Sizing Safety Valve Vent Pipes for Saturated Steam

1982 ◽  
Vol 104 (1) ◽  
pp. 247-251
Author(s):  
H. E. Brandmaier
Keyword(s):  
Ideal Gas ◽  
Gas Analysis ◽  
Saturated Steam ◽  
Flow Conditions ◽  
Flow Properties ◽  
Pipe Length ◽  
One Dimensional ◽  
Choked Flow ◽  
Pipe Outlet ◽  
Orifice Valve

An earlier one-dimensional ideal gas analysis was changed to incorporate equilibrium properties of steam as given by the 1967 ASME steam tables. A generalized procedure based on pressure and entropy as independent variables is used to calculate choked flow conditions at the valve orifice, valve pipe outlet and vent pipe outlet. At the third location, the results are independent of whether flow in the vent pipe is supersonic or subsonic. An integral method is used to calculate the vent pipe length required to choke the flow. Computed data are compared with ideal gas data. The vent pipe size, to prevent blowback into the powerplant, is less conservative using real steam data. The flow properties, particularly specific volume, are significantly different.

‘Each Song Was Just Like a Little Sermon’

2018 ◽  
Author(s):  
Isaac Land
Keyword(s):  
Nineteenth Century ◽  
Golden Age ◽  
Military Training ◽  
One Dimensional ◽  
National Pride ◽  
Recent Scholarship ◽  
The Relationship

This chapter is central to the volume’s chronological contentions, as its argument accounts for the specialized, one-dimensional Dibdin of ‘Tom Bowling’ that has endured into recent scholarship. Focusing on Dibdin’s posthumous reception, it examines the moral and rhetorical difficulties of repackaging Dibdin’s works for a Victorian sensibility; it explores the specifics of mid-century concert culture previously highlighted by Derek Scott and William Weber as central to changes in nineteenth-century taste and programming; and it develops the theme of nostalgia into a revelatory consideration of the relationship between new naval technologies, national pride, and military training, and the songs, people, and language of a remembered Napoleonic ‘golden age’—to which Dibdin proves to have been as central, in the Victorian imagination, as Nelson.

Effect of mechanical restraint on the rate of corrosion in concrete

1998 ◽  
Vol 25 (1) ◽  
pp. 81-86 ◽  
Author(s):  
N Hearn ◽  
J Aiello
Keyword(s):  
Mix Design ◽  
Concrete Repair ◽  
Accelerated Corrosion ◽  
One Dimensional ◽  
Mechanical Restraint ◽  
Corrosion Rates ◽  
Accelerated Corrosion Tests ◽  
The Matrix ◽  
The Relationship

Experimental work on prismatic concrete specimens was conducted to determine the relationship between mechanical restraint and the rate of corrosion. The current together with the changes in strain of the confining frame were monitored during the accelerated corrosion tests. The effect of mix design and cracking on the corrosion rates was also investigated. The results show that one-dimensional mechanical restraint retards the corrosion process, as indicated by the reduction in the steel loss. Improved quality of the matrix, with and without cracking, reduces the rate of steel loss. In the inferior quality concrete, the effect of cracking on the corrosion rate is minimal.Key words: corrosion, concrete, repair.

scholarly journals Not Only Mania or Depression: Mixed States/Mixed Features in Paediatric Bipolar Disorders

2021 ◽  
Vol 11 (4) ◽  
pp. 434
Author(s):  
Delfina Janiri ◽  
Eliana Conte ◽  
Ilaria De Luca ◽  
Maria Velia Simone ◽  
Lorenzo Moccia ◽  
...  
Keyword(s):  
Systematic Review ◽  
Bipolar Disorders ◽  
Prevalence Rates ◽  
Mixed States ◽  
Total Patient ◽  
Hyperactivity Disorder ◽  
Mixed Features ◽  
Paediatric Age ◽  
Meta Analyses ◽  
The Relationship

Background: early onset is frequent in Bipolar Disorders (BDs), and it is characterised by the occurrence of mixed states (or mixed features). In this systematic review, we aimed to confirm and extend these observations by providing the prevalence rates of mixed states/features and data on associated clinical, pharmacological and psychopathological features. Methods: following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched from inception to 9 February 2021 for all studies investigating mixed states/mixed features in paediatric BD. Data were independently extracted by multiple observers. The prevalence rates of mixed states/features for each study were calculated. Results: eleven studies were included in our review, involving a total patient population of 1365 individuals. Overall, of the patients with paediatric age BD, 55.2% had mixed states/features (95% CI 40.1–70.3). Children with mixed states/features presented with high rates of comorbidities, in particular, with Attention Deficit Hyperactivity Disorder (ADHD). Evidences regarding the psychopathology and treatment response of mixed states/features are currently insufficient. Conclusions: our findings suggested that mixed states/features are extremely frequent in children and adolescents with BD and are characterised by high levels of comorbidity. Future investigations should focus on the relationship between mixed states/features and psychopathological dimensions as well as on the response to pharmacological treatment.

The combined effect of lattice’s uniaxial strains and electron–phonon interaction’s screening on TBEC of the intersite bipolarons

2016 ◽  
Vol 30 (26) ◽  
pp. 1650186
Author(s):  
B. Yavidov ◽  
SH. Djumanov ◽  
T. Saparbaev ◽  
O. Ganiyev ◽  
S. Zholdassova ◽  
...  
Keyword(s):  
Ideal Gas ◽  
Einstein Condensation ◽  
Chain Model ◽  
One Dimensional ◽  
Electron Phonon Interaction ◽  
Model Lattice ◽  
Experimental Values ◽  
Bose Einstein ◽  
Derivatives Of ◽  
The Ideal

Having accepted a more generalized form for density-displacement type electron–phonon interaction (EPI) force we studied the simultaneous effect of uniaxial strains and EPI’s screening on the temperature of Bose–Einstein condensation [Formula: see text] of the ideal gas of intersite bipolarons. [Formula: see text] of the ideal gas of intersite bipolarons is calculated as a function of both strain and screening radius for a one-dimensional chain model of cuprates within the framework of Extended Holstein–Hubbard model. It is shown that the chain model lattice comprises the essential features of cuprates regarding of strain and screening effects on transition temperature [Formula: see text] of superconductivity. The obtained values of strain derivatives of [Formula: see text] [Formula: see text] are in qualitative agreement with the experimental values of [Formula: see text] [Formula: see text] of La[Formula: see text]Sr[Formula: see text]CuO4 under moderate screening regimes.

Optimize Mixing Process Parameters of Synchronous Rotor Mixer Based on Orthogonal Method

2012 ◽  
Vol 501 ◽  
pp. 442-447
Author(s):  
Ping Fu ◽  
Feng Bao Bai ◽  
Chuan Sheng Wang ◽  
Shan Hu Li
Keyword(s):  
Physical Properties ◽  
Process Parameters ◽  
Fill Factor ◽  
Cooling Water ◽  
Mixing Process ◽  
Rotor Speed ◽  
Orthogonal Method ◽  
Cooling Water Temperature ◽  
Vulcanized Rubber ◽  
The Relationship

In this paper adopting the orthogonal method, self-developed compound formulation had tested, and the relationship between the physical properties of vulcanized rubber and rectangular synchronous rotor mixer parameters had researched. The results showed that when the fill factor was 0.6, the rotor speed was 70r/min, cooling water temperature was 45 °C, pressure on the top bolt was 0.8Mpa, the physical properties of the vulcanized rubber was best.

The oxygen dissociation curve of haemoglobin in dilute solution

1936 ◽  
Vol 120 (819) ◽  
pp. 484-495 ◽  
Keyword(s):  
Spectroscopic Method ◽  
Marked Change ◽  
Maternal Blood ◽  
Gas Analysis ◽  
Dilute Solution ◽  
Dissociation Curve ◽  
Foetal Haemoglobin ◽  
Oxygen Dissociation ◽  
Dissociation Curves ◽  
The Relationship

The spectroscopic determination of the oxygen dissociation curves of haemoglobin has an advantage over the tonometer and gas analysis method, in that much smaller quantities of haemoglobin can be made use of. The spectroscopic method was used to determine the relationship between the foetal and maternal haemoglobins in the sheep during a study of foetal respiration made by Barcroft (1935). The conditions for the comparison of the haemoglobins were a dilute solution of the haemoglobin at p H 9·2 (borate buffer) and at 20° C. These conditions were chosen because of the very accurate determinations of the dissociation curves of dilute haemoglobin of the sheep by Forbes and Roughton (1931) and because these authors recommend p H 9·2 at room temperature as most suitable for a study of the oxygen equilibrium of haemoglobin, all the haemoglobin being in the form of the alkali salt. McCarthy (1933) and Hall (1934) had found previously that the haemoglobins of the foetal and maternal goat were different, the foetal haemoglobin (in the blood and as purified haemoglobin) having a higher affinity for oxygen. The same relationship was found to exist in the sheep haemoglobins in dilute solution at 20° C and p H 9·2. When samples of human foetal and maternal blood (sent by Professor Fleming from the Obstetrical Department of the Royal Free Hospital) were compared in dilute solution it was found that the foetal haemoglobin had a lower affinity for oxygen than the maternal. This was also found by Haurowitz (1935) for dilute solutions of the haemoglobins of mother and new born infant. Haurowitz, however, pointed out that in the corpuscles the affinity for oxygen is less in the infant’s haemoglobin than in that of the mother, but the method used by him did not allow of measurements on suspensions of corpuscles. In the present work the dissociation curves of dilute suspensions of corpuscles have been compared with similar solutions of the haemoglobin. It was found that the relationship of the dissociation curves for human foetal and maternal corpuscles is the same as that found by Barcroft in the goat and in the sheep. It has now been found that by a dilution of human adult haemoglobin the dissociation curve is altered by 200% to a position of higher affinity for oxygen, without any marked change in shape. The haemoglobin of the human foetus, on the other hand, is much less affected by dilution, thus explaining the anomaly of the reversed relationship when solutions of the haemoglobins are used instead of suspensions of corpuscles. It was shown by the work of Bock, Field, and Adair (1924), and by Adair (1925), that a solution of haemoglobin free from stromata and of a similar concentration to blood gives a dissociation curve like whole blood. This makes it clear that in the comparison of dilute haemoglobin solutions with suspensions of corpuscles we are concerned, not simply with a change in the haemoglobin due to haemolysis, but a change due to a dilution of the contents of the corpuscle.

scholarly journals A Novel Approach to the Analysis of the Soil Consolidation Problem by Using Non-Classical Rheological Schemes

2021 ◽  
Vol 11 (5) ◽  
pp. 1980
Author(s):  
Kazimierz Józefiak ◽  
Artur Zbiciak ◽  
Karol Brzeziński ◽  
Maciej Maślakowski
Keyword(s):  
Constitutive Models ◽  
Organic Soil ◽  
Organic Soils ◽  
Soil Consolidation ◽  
Flexible Tool ◽  
One Dimensional ◽  
Novel Approach ◽  
Soil Skeleton ◽  
The One ◽  
The Relationship

The paper presents classical and non-classical rheological schemes used to formulate constitutive models of the one-dimensional consolidation problem. The authors paid special attention to the secondary consolidation effects in organic soils as well as the soil over-consolidation phenomenon. The systems of partial differential equations were formulated for every model and solved numerically to obtain settlement curves. Selected numerical results were compared with standard oedometer laboratory test data carried out by the authors on organic soil samples. Additionally, plasticity phenomenon and non-classical rheological elements were included in order to take into account soil over-consolidation behaviour in the one-dimensional settlement model. A new way of formulating constitutive equations for the soil skeleton and predicting the relationship between the effective stress and strain or void ratio was presented. Rheological structures provide a flexible tool for creating complex constitutive relationships of soil.

A Study of a Sharp 90 Degree Curved Flow

1992 ◽  
Author(s):  
R. H. Kim
Keyword(s):  
Turbulence Model ◽  
Ideal Gas ◽  
Radius Of Curvature ◽  
Dimensional Theory ◽  
One Dimensional ◽  
Algebraic Stress Model ◽  
Finite Difference Technique ◽  
Curved Tube ◽  
Kinetic Energy Loss ◽  
The Ideal

Abstract An investigation of air flow along a 90 degree elbow-like tube is conducted to determine the velocity and temperature distributions of the flow. The tube has a sharp 90 degree turn with a radius of curvature of almost zero. The flow is assumed to be a steady two-dimensional turbulent flow satisfying the ideal gas relation. The flow will be analyzed using a finite difference technique with the K-ε turbulence model, and the algebraic stress model (ASM). The FLUENT code was used to determine the parameter distributions in the passage. There are certain conditions for which the K-ε model does not describe the fluid phenomenon properly. For these conditions, an alternative turbulence model, the ASM with or without QUICK was employed. FLUENT has these models among its features. The results are compared with the result computed by using elementary one-dimensional theory including the kinetic energy loss along the passage of the sharp 90 degree curved tube.

scholarly journals Estimation for Two-Dimensional Nonsymmetric Coherently Distributed Source in L-Shaped Arrays

2018 ◽  
Vol 2018 ◽  
pp. 1-16
Author(s):  
Tao Wu ◽  
Zhenghong Deng ◽  
Qingyue Gu ◽  
Jiwei Xu
Keyword(s):  
Expectation Maximization ◽  
Two Dimensional ◽  
Signal Distribution ◽  
Distributed Source ◽  
One Dimensional ◽  
Least Squares Estimators ◽  
Iterative Calculation ◽  
Symmetric Source ◽  
Relationship Of ◽  
The Relationship

We explore the estimation of a two-dimensional (2D) nonsymmetric coherently distributed (CD) source using L-shaped arrays. Compared with a symmetric source, the modeling and estimation of a nonsymmetric source are more practical. A nonsymmetric CD source is established through modeling the deterministic angular signal distribution function as a summation of Gaussian probability density functions. Parameter estimation of the nonsymmetric distributed source is proposed under an expectation maximization (EM) framework. The proposed EM iterative calculation contains three steps in each cycle. Firstly, the nominal azimuth angles and nominal elevation angles of Gaussian components in the nonsymmetric source are obtained from the relationship of rotational invariance matrices. Then, angular spreads can be solved through one-dimensional (1D) searching based on nominal angles. Finally, the powers of Gaussian components are obtained by solving least-squares estimators. Simulations are conducted to verify the effectiveness of the nonsymmetric CD model and estimation technique.

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