DOI: 10.4236/ojfd.2019.93014 219 Open Journal of Fluid Dynamics In order to compare the outlet axial velocity of the two models carefully, the axial velocity at Z = 140 mm is presented in Figure 14. As can be seen in Figure 14, the axial velocities at 0% - 10% span for both models are similar and less than zero, which means there is backflow near the hub. At 10% - 90% span, the axial velocities of the optimal model are much higher than those of the original model. Moreover, at 30% - 80% span, the axial velocity gradients along the spanwise of the optimal model decrease obviously, which would improve the flow field and reduce the flow losses. In addition, the axial velocity at 90% - 100% span of the optimal model is smaller than that of the original model, which would decrease the tip leakage flow rate. It can be concluded that the average axial velocity of the optimal velocity increases and the axial velocity distribution becomes reasonable, which would be beneficial to increase the volume flow rate of the axial fan.
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The reaction conditions were membrane area 36.3×10 -4 m 2 , membrane thickness 1.732 mm, membrane porosity 68% and the rate constant (k) 0.0607 s -1 . Substituting all the known parameters into Eq. 22 and Eq. 24, Eq. 32 and Eq. 33 was obtained. Eq. 32 and Eq. 33 were solved as a function of volume flow rate in order to predict the effect of volume flow rate on the conversion of seven times cycle reaction and seven sheet membranes reaction in the membrane reactor, respectively. The functional relationship between conversion (x) and volume flow rate (R) of catalytic membranes is shown in Fig. 6(c).
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five different vessels—PA, PV, subcutaneous saphenous veins (S1, S2, S3) —and muscle; from top to bottom, re- spectively. The solid lines drawn through them result from linear-least-squares (LLS) fittings. The root-mean- square, χ, values for all vessels are greater than 0.95 ex- cept for PA, for which it is 0.88. The slope value of each line essentially represents the maximum flow velocity (F l,m ) of each vessel. The volume flow rate (F v , Table 1)
ABSTRACT: Hydrogen is being considered as a primary automotive fuel and as a replacement for conventional fuels. Some of the desirable properties, like high flame velocity, high calorific value motivate to use hydrogen fuel in a dual fuel mode in diesel engine. In this experiment the hydrogen was inducted in the inlet manifold with intake air. The experiments were conducted on a four stroke, single cylinder, water cooled, direct injection (DI), diesel engine at a speed of 1500 rpm. Hydrogen was stored in a high pressure cylinder and supplied to inlet manifold through water and air based flame arrestor. The pressure regulator was used to reduce the cylinder pressure from 140 bar to 2 bar. The hydrogen was inducted with various volume flow rates namely 4lpm, 6lpm and 8lpm respectively by digital volume flow meter. The engine performance, emission and combustion parameters were analyzed at various flow rates of hydrogen and compared with diesel fuel operation. The brake thermal efficiency (BTE) increased and brake specific fuel consumption (BSFC) decreased for hydrogen flow rate of 8lpm as compared to diesel and lower volume flow rate of hydrogen. The hydrocarbon (HC) and carbon monoxide (CO) decreased and the oxides of nitrogen (NOx) increased for higher volume flow rate of hydrogen compared to diesel and lower volume flow rate of hydrogen. The heat release rate and cylinder pressure increased for higher volume flow rate of hydrogen compared to diesel and lower volume flow rate of hydrogen.
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mechanical power actually needed at the tool to remove material that is thermally dissipated by the internal flow of the coolant. Similarly, a specific efficiency ratio r’ is also defined by considering the mechanical power per volume flow rate of the material removed and the dissipated thermal power per volume flow rate of the coolant. Both r and r’ are then analysed in a 3 3
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In this study a simple technique is used to find out the viscosity of diabetic blood, plasma and RBC at different flow rates by using normal capillary tube. The tool is developed based on the Poiseuille’s theory to measure the coefficient of viscosity and volume flow rate of blood,plasma and RBC for different radii The data is presented and findings and conclusions are drawn from the data.
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580 nm, 4.3 ml/min flow rate and 6 ppm of aniline blue dye , the effect of sample volume (changing loop) was studied and response was recorded for each loop. the volume of sample under study were 3.9.25 , 78.5 , 117 and 157 microliter. The result showed in figure 3 . When the sample volume Increase the response was increased , after 117 and 157 µl the response remain constant. This effect is similar to results for FIA unit used for determination of water toxicity 35 and determination of magnesium 36 . Although the response for 117 and 157 are equal ,
The present investigation was carried out to find the role of glutamate in development of depression in asthma using mice. Female albino mice were divided into five groups, group I- normal control, group II- depression, group III- asthma, group IV- asthma+depression and group V- memantine-treated asthma+depression. Various respiratory parameters, histopathology of lungs, forced swim test, sucrose preference test and brain neurotransmitter levels were measured. A significant decrease in tidal volume and air flow rate as well as increase in respiratory rate was found in depression asthmatic group as compared to only asthmatic group, only depression group and normal control group. These same animals when subjected to despair swim test and sucrose preference test, the immobility time was significantly increased whereas preference to the sucrose solution was significantly decreased. Glutamate, 5-HT and norepinephrine levels were significantly increased and dopamine level significantly decreased in depression group and depression along with asthma group as compared to normal control group or asthma group. Treatment with memantine showed improvement in the respiratory parameters and depression parameters as compared to untreated asthmatic mice with depression. Moreover, a positive correlation was observed between airflow rate and immobility. Also, a direct correlation was observed between brain glutamate level and airflow rate as well as brain glutamate level and immobility. These results suggested that glutamate might be the key mediator involved in development of depression in asthma.
hydraulic retention time depends on several parameters like flow rate of effluent through the vermifiltration bed, volume and quality of soil used for the vermifiltration bed. During the H.R.T the earthworms present in the filtration unit eat organic pollutants present in the effluent and decompose it. This biological activity of earthworms along with sand and gravel media reduces the BOD and COD values of the effluent and also total suspended or dissolved solids present in it.
Find the wet bulb temperature on the top, left-hand (curved) edge of the chart which is the saturation line. Travel down the dotted line of constant wet bulb temperature (at around 30° to the horizontal) until it intersects the vertical line coming up from the dry bulb temperature (which is found on the horizontal axis). The point at which the two lines meet fully describes the conditions. The humidity ratio (or specific humidity) can be read off the vertical axis. The specific enthalpy of the air/vapour mixture per kg of dry air can be found by travelling up the solid lines approximately parallel to the wet bulb lines, while the specific volume of the mixture can be found by interpolating between the lines at approximately 70° to the horizontal.
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were also used for the simulation of flow in the Chiari model. We assumed a pressure at the top of the model corresponding to 20 cm of water. We assumed a plug-shaped inflow velocity profile varying si- Fig 1. The idealized model (A) of a subarachnoid space with herniated tonsils and the original model (B) with normally positioned tonsils. The models are shown with sagittal MR images illustrating a typical normal individual and a typical Chiari I malformation. For the normal model, a midline sagittal plane is shown and for the tonsillar herniation case, its paramedian through the nearest tonsil. A white reference line indicates the midpoint of the model at the correlate of the craniovertebral junction. The extensions to the model to facilitate the description of boundary conditions are demonstrated by the red lines. Anterior is to the reader’s left and posterior to the right.
nanofluid leading to increase in friction factor. Zan Wu et al.  has carried out experimental investigation on the pressure drop and convective heat transfer characteristics of water and five alumina/water nanofluids of weight concentrations from 0.78% wt. to 7.04% wt. for both laminar flow and turbulent flow inside a double- pipe helically coiled heat exchanger. For both laminar flow and turbulent flow, no anomalous heat transfer enhancement was found. The heat transfer enhancement of the five nanofluids over tap water ranges from 0.37% to 3.43% for the constant flow velocity basis for both laminar and turbulent flows. E. Esmaeilzadeh et al.  conducted experimental study to investigate heat transfer and friction factor characteristics of g- Al 2 O 3 /water
The retention times of analyte (AT) and internal standard (ATD8) were eluted at 1.42 ± 0.2 min and 1.44 ± 0.2 min respectively with 3 min total runtime. Different procedures like PPT (Protein precipitation), SPE (solid phase extraction) and LLE (liquid-liquid extraction) methods were optimized. Out of all, it was observed that the PPT was suitable due to simple extraction, high recovery and the less ion suppression effect on drug and internal standard. Electro spray ionization (ESI) provided a maximum response over atmospheric pressure chemical ionization (APCI) mode, and was chosen for this method. The instrument was optimized to obtain sensitivity and signal stability during infusion of the analyte in the continuous flow of mobile phase to electrospray ion source operated at a flow rate of 20 μl/min. Alectinib gave more response in positive ion mode as compare to the negative ion mode.
basic fluid dynamic principles required for the calculations are outlined, but ultimately the equations are not derived comprehensively. Similarly, the coursework provided by the Air Pollution Training Institute on air sampling (APTI, 1980) presents only the calibration equations along with a multi- tude of numerical examples, without explaining their origin. Even governmental regulations (40 CFR Appendix B Part 50, US EPA, 2011) and guidelines (US EPA, 1999) focus on the calibration of Hi-Vol samplers but do not derive the proce- dure in detail. The early literature does not elaborate on the calibration equations. For example, Lynam et al. (1969) in- vestigate different calibration methods for Hi-Vol samplers, showing that significant differences can occur. Similarly, Lee et al. (1972) investigate different methods for measuring sus- pended particles in air and elaborate in detail on the calibra- tion process of Hi-Vol samplers without deriving any equa- tions. As recently as 2013, ASTM International (2013), in Method D6209-13 for collection of Hi-Vol samples, leave several blanks in sections covering flow control, flow calibra- tion, calibration orifices, and roots meters (Sect. 9.1.2, 9.1.3, 9.1.4 and 9.1.5), all of which are critical to proper calibra- tion. In the calibration section of this method (12.1), there are references to these blanks in Sect. 9.1. Most studies of atmo- spheric contaminants collected with Hi-Vol samplers assume that the calibration procedure is understood, rarely discuss calibration details, and never include the equations used, this includes Hermanson and Hites (1989), Monosmith and Her- manson (1996), Hermanson et al. (1997, 2003, 2007), Basu et al. (2009), Salamova et al. (2014), and Hites (2018).
different dimensionless time. As it can be seen, the velocity at different dimensionless time varies vice versa during a period due to the change of the pressure gradient. The nanofluid velocity in a channel changes from zero at the surface because of the no-slip condition to a maximum at the channel center. The thickness of this boundary layer increases in the flow direction until the boundary layer reaches the channel center and thus fills the entire channel, as shown in Fig. 14. Near the wall, the velocity gradient becomes very large, corresponding to the boundary layer and is called the boundary region. In the buffer region between the channel center and the boundary regions, a velocity ‘‘overshoot’’ occurs at a few moments, for example, at τ = 5 and 25, shown in Fig. 14. That means the flow velocity at these moments exceeds the velocity at channel center and, hence, causes larger velocity gradient at the wall than that in steady-state flow. Consequently, more heat is transported at these moments. This phenomenon is also called Richardson effect .
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D etailed knowledge o f the liquid-liquid hydrodynam ics in CCC m achines is o f great im portance if accurate calculation o f chrom atographic param eters, such as solute distribution and column efficiency, is to be achieved. Furtherm ore, as w ill be dem onstrated in Chapter 8, knowledge o f the hydrodynam ics at different scales o f operation is im portant if accurate scale-up predictions o f the solute elution tim e are to be achieved. Liquid-liquid hydrodynam ics in the J-type CCC m achines have been extensively studied for a wide range o f binary, ternary and quaternary phase systems, w ith a linear relationship between the square root o f m obile phase flow (F^^) and the degree o f stationary phase retention (S/) shown to apply for all phase system s (D u et al., 1999). This relationship between S/ and F^'^ enables the accurate determ ination o f stationary phase retention over the range o f operational flow rates investigated sim ply by perform ing two retention tests (Sutherland, 2000a). Extended hydrodynam ic studies by Sutherland (2000a), based on the observed correlation betw een retention and flow (D u et al., 1999) have also shown there to be a linear relationship betw een S/ and the linear m obile phase velocity (u).
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The study result shows that heat removal coefficient increases proportionally with volume fraction as shown in figure 7. This is attributed to the improved conductivity with higher volume fraction. The mass flow rate of the hot water was kept constant at 6 l/min. About 16% and 34.4% enhancement was found for 0.1 and 0.3 vol% respectively. Therefore heat exchanger area reduction shall be achieved with 0.3 vol%. Similarly maximum heat transfer enhancement of about 6 % was observed at 0.3 Vol%. Fig 8 shows the heat transfer enhancement for different volume fraction.
tigo, such as benign paroxysmal positional vertigo, vestibular neuronitis, Me´nie`re disease, and so on. Recent approaches to monitor degeneration of the brain stem or stenosis of the basilar or vertebral arteries with MR imaging or MR angiography have provided valuable means for the diagnosis of PCI (8–10). However, these means are limited in that their evaluations are qualitative rather than quantita- tive. Recent advances in MR angiography hardware and software have enabled measurements of blood flow velocity and flow volume rate (12–16). In this study, we used contrast-enhanced 2D cine phase MR angiography to measure quantitative blood flow of the basilar artery in patients with PCI who had com- plained primarily of dizziness and who had the diag- nosis of PCI on the basis of clinical findings.
Fibrosis (f2,3,4) (%) 1/15 (6.7%) 14/33 (42.4%) 0.01 HBs-Ag hepatitis B surface antigen, HCV-Ab hepatitis C virus antibody, WBC white blood cell, Hb hemoglobin, Plt platelet, CRP C-reactive protein, PT prothrombin time, AST aspartate aminotransferase, ALT alanine aminotransferase, Che cholinesterase, Alb albumin, HbA1c A1c glycated hemoglobin, ICGR15 indocyanine green retention test at 15 min, 99mTc-GSA technetium 99 m diethylenetriaminepentaacetic acid-galactosyl-human serum albumin, LHL15, receptor index: uptake ratio of the liver to that of the liver plus heart at 15 min of technetium 99 m diethylenetriaminepentaacetic acid- galactosyl-human serum albumin scintigraphy, PVP portal venous pressure, PTPE percutaneous transhepatic portal embolization, IR-pFV increase rate of portal venous flow volume
For several decades now, an air vessel has been believed to be a vital component in improving the pumping efficiency of a conventional hydram water pumping system (Rajput, 2009; Ojha et al., 2011). However the matching of an appropriate air vessel volume to a hydram pump of a particular size had so far been irrationally handled as there were several differing opinions from several hydram pump researchers. For example a researcher Mitchell (1977) had argued that there was no maximum limit for the air vessel size (volume - wise) to be used in hydrams. Likewise in the recent hydram pump developments, a designer named Bamford, (Bamford, 2002) was reported to have made a hydram pump which could pump water without necessarily using an air vessel