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A 50%-chord trailing edge flap was fitted to a NACA 0006 airfoil spanning the test section of a water tunnel, equipped with a suite of electric linear motors to produce a range of flap deflection f...

This paper presents a study on the effect of solidity and airfoil profile on the performance of Vertical Axis Wind Turbines (VAWTs). A 1.1 kW commercially viable Darrieus VAWT was studied using ANSYS Fluent. Four different airfoils – NACA 0012, NACA 0015, NACA 0030 and AIR 001 – were considered in the analysis. The tip speed ratios (λ) were varied from 1 to 2.5 with an incoming wind velocity of 10 m/s. It was observed that NACA 0030 performed better at lower values of λ due to long duration of attached flow; while NACA 0012 performed better at λ > 1.8 with a wider range of λ. The shed vortex dissipates much faster for thinner airfoils than for thicker airfoils at higher values of λ. Two bladed VAWTs generated more power than the three bladed turbines. This indicated that turbines with lower solidity perform better at high λ.

The development of coherent structures within the laminar separation bubble that forms on a NACA 0018 airfoil at an angle of attack of 8 deg and a chord-based Reynolds number of 100,000 is investig...

In this paper, a robust Linear Quadratic Regulator (LQR) of a NACA 0018 wing with a flap actuator is developed for stall flutter suppression. The nonlinear and switched set of equations of the aeroelastic model is detailed and conveniently expressed as a polytopic uncertain system. A Linear Matrix Inequalities (LMIs) formulation of the LQR problem in the presence of uncertainties is used for the control design. Simulation results confirm the desirable behavior of the arising closed-loop system.

Post-stall flow structure and surface pressures are evaluated to determine the effects of large angles of attack, perching like manoeuvres on the flow about a NACA 0021 airfoil exposed to dynamic s...

In this paper, we investigated the effect of profile modifications on straight bladed VAWTs equipped with symmetrical aerofoil (NACA 4-digit series of NACA 0012, NACA 0015, NACA 0018, and NACA 0021). Aerofoil profile modifications being investigated, consists of only Gurney flap, only inward dimple and combination of both Gurney flap and dimple. In this work, we focused on the values of lift, aerofoil velocity and aerofoil forces as these are the vital parameters, which are used as the parameters to measure for power generated by the turbine by Energy and the Spalart Allmaras models. All the design modifications and simulation analysis have been done with the help of CFD by using ANSYS Fluent. The results of the modified profiles are compared in terms of lift coefficient (CL), velocity (V) and blade force (F). These results are further validated with previous experimental results at same boundary conditions for to ensure the reliability of the analysis. The overall results show that NACA 0012 and NACA 0015 gives better performance in all three aspects of results (coefficient of lift, velocity, and force). Hence, present modifications are best suitable for increasing the performance of NACA 0012 and NACA 15 symmetrical aerofoil straight bladed VAWTs.

Este trabajo detalla en general, el estado del arte en turbinas hidrocinéticas y en particular el estudio y diseño de una turbina hidrocinética para la Patagonia Austral. Para ello, inicialmente, se abarcó el estudio de la situación de dichos sistemas conversores tanto en el ámbito internacional como local, permitiendo observar así que poseen tecnología en desarrollo, dado que no hay un tipo definido en la Patagonia Austral, se siguió la metodología del Ciclo de Vida, o sea ir cumpliendo las etapas desde el estudio del recurso, concepción del prototipo y diseño según las necesidades 2014-2015 del PI 29B163 al cual está asociado este trabajo. En la aplicación se tuvo en cuenta la situación sea fluvial o marítima. En el caso del estudio del recurso se realizó la estimación energética de las corrientes sub acuáticas y los aspectos físicos o ambientales de los ríos a tener en cuenta a la hora de iniciar un proyecto en el cual se empleará este tipo de tecnología. Para el caso de concepción del prototipo o diseño conceptual se parte del estudio del proceso de transformación de energía en los mismos y cuáles son las principales características de los distintos elementos que conforman una turbina hidrocinética. Finalmente en el diseño, con los valores de la velocidad de corriente de agua promedio se define el diámetro de la turbina según una demanda estimada y se establecen las pautas de qué materiales se pueden utilizar.En esencia, este proyecto permite tener un conocimiento teórico acerca de los sistemas conversores hidrocinéticos y las necesidades prácticas para llevar a cabo un prototipo de dimensiones acotadas en un lugar determinado como podría ser Puerto san Julián.

Background The present study sought to evaluate the efficacy of N-acetylcysteine amide (NACA) eye drops in reversing the cataract formation induced by sodium selenite in male Wistar rat pups. Methods Forty male Wistar rat pups were randomly divided into a control group, an N-acetylcysteine amide-only group, a sodium selenite-induced cataract group, and a NACA-treated sodium selenite-induced cataract group. Sodium selenite was injected intraperitoneally on postpartum day 10, whereas N-acetylcysteine amide was injected intraperitoneally on postpartum days 9, 11, and 13 in the respective groups. Cataracts were evaluated at the end of week 2 (postpartum day 14) when the rat pups opened their eyes. N-acetylcysteine amide eye drops were administered beginning on week 3 until the end of week 4 (postpartum days 15 to 30), and the rats were sacrificed at the end of week 4. Lenses were isolated and examined for oxidative stress parameters such as glutathione, lipid peroxidation, and calcium levels along with the glutathione reductase and thioltransferase enzyme activities. Casein zymography and Western blot of m-calpain were performed using the water soluble fraction of lens proteins. Results Morphological examination of the lenses in the NACA-treated group indicated that NACA was able to reverse the cataract grade. In addition, glutathione level, thioltransferase activity, m-calpain activity, and m-calpain level (as assessed by Western blot) were all significantly higher in the NACA-treated group than in the sodium selenite-induced cataract group. Furthermore, sodium selenite- injected rat pups had significantly higher levels of malondialdehyde, glutathione reductase enzyme activity, and calcium levels, which were reduced to control levels upon treatment with NACA. Conclusions The data suggest that NACA has the potential to significantly improve vision and decrease the burden of cataract-related loss of function. Prevention and reversal of cataract formation could have a global impact. Development of pharmacological agents like NACA may eventually prevent cataract formation in high-risk populations and may prevent progression of early-stage cataracts. This brings a paradigm shift from expensive surgical treatment of cataracts to relatively inexpensive prevention of vision loss.

The aerodynamic noise of a NACA 0012 and NACA 0021 aerofoil is measured and compared in order to determine whether there are differences in their noise signatures with a focus on the onset of stall. Measurements of the self-noise of each aerofoil are measured in an open-jet Anechoic Wind Tunnel at Reynolds numbers of 64,000 and 96,000, at geometric angles of attack from −5° through 40° at a resolution of 1°. Further measurements are taken at Re = 96,000 at geometric angles of attack from −5 through 16° at a resolution of 0.5°. Results show that while the noise generated far into the stall regime is quite similar for both aerofoils the change in noise level at the onset of stall is significantly different between the two aerofoils with the NACA 0021 exhibiting a much sharper increase in noise levels below a chord-based Strouhal number of Stc = 1.1. This behaviour is consistent with the changes in lift of these aerofoils as well as the rate of collapse of the suction peak of a NACA 0012 aerofoil under these flow conditions.

Printed circuit heat exchanger (PCHE) can be used in supercritical carbon dioxide (S-CO 2 ) Brayton cycle. The present study compares NACA 0020 airfoil fin PCHE with conventional zigzag PCHE by numerical analysis. Pressure drop of the former has a striking reduction while maintaining excellent heat transfer performance. Comparison on four NACA 00XX series airfoil fin PCHEs is performed to investigate the influence of airfoil profile on flow and heat transfer performance. With a fixed vertical pitch, heat transfer performance of NACA series airfoil fin PCHE increases as airfoil thickness increases. However, comprehensive performance, in which both flow and heat transfer are taken into account, degrades with increasing airfoil thickness. Among four NACA airfoil fin PCHEs presented in this paper, NACA 0010 airfoil fin PCHE demonstrates the best comprehensive performance.

Background: Age-related macular degeneration (AMD) is a leading cause of blindness in the United States among adults age 60 and older. While oxidative stress is implicated in the pathogenesis of AMD, dietary antioxidants have been shown to delay AMD progression in clinical studies. We hypothesized that N-acetylcysteine amide (NACA), a thiol antioxidant, would protect retinal pigment epithelium and impede progression of retinal degeneration. Methods: tert-Butyl hydroperoxide (TBHP) was used to induce oxidative stress in cell cultures. The goal was to evaluate the efficacy of NACA in an in vitro model of AMD in primary human retinal pigment epithelial cells (HRPEpiC). Results: Our data indicates that TBHP generated reactive oxygen species (ROS), which reduced cell viability, depleted glutathione (GSH) levels, and compromised glutathione reductase (GR) activity. Pretreatment with NACA significantly reduced ROS generation, restored GSH levels and GR activity, and recovered transepithelial electrical resistance. Pretreatment with NACA did not decrease the number of dying cells as determined by flow cytometry analysis. However, survival was significantly improved when cells were co-exposed to NACA and TBHP after a shortened pretreatment period. Conclusion: Our data suggest that pretreatment with NACA reduces sublethal but not lethal effects of TBHP in HRPEpiC. NACA significantly improves cell survival when administered prior to and during oxidative damage similar to that observed in the development of dry AMD. These results indicate that continuation of a thiol antioxidant regimen for treatment of AMD is beneficial throughout the course of the disease, and NACA is a potent antioxidant that should be further evaluated for this purpose.

The lift and drag coefficient plots for any airfoil provides a means for measuring its aerodynamic characteristics. These are very useful in deciding if a particular airfoil is appropriate for any particular application area. This study computationally predicts how the lift coefficient, drag coefficient and drag polar derived for the aerodynamic flow over the NACA 4412 airfoil vary with angles of attack. The effect of varying Reynolds number on the aerodynamic characteristics was also investigated. The finite-volume based computational fluid dynamics code; ANSYS Fluent was used to solve the continuity equation, the Reynolds Averaged Navier-Stokes equation and the turbulence transport equations governing the flow. For the range of Reynolds number considered, flow was taken as incompressible, steady and two-dimensional. Simulations were run for angles of attack ranging from -10° to 18° with an interval of 2° and for a Reynolds number range of 1.0 x 106 to 13.0 x 106. Results at a given Reynolds number revealed a steady variation between lift coefficient and angle of attack within the pre-stall region and a gradually increasing curve for the drag coefficients. A constant stalling angle at 14° with gradually increasing value for the maximum lift coefficient was recorded as the Reynolds number increased. The drag polar was also found to be constant at 6° for all the ranges of Reynolds number. The results obtained showed that numerically solving for flow problems is a valid approach for obtaining the aerodynamic characteristics of an airfoil since the results were compared with data from wind tunnel tests.

Darrieus wind turbines are simple lift based machines with exceptionally high efficiencies in terms of power coefficient compared to similar drag based vertical axis turbines. However, in low Reynolds numbers, a notable performance loss was reported. As a potential solution, truncated NACA 0018 airfoil (NACA 0018TC-39) has been introduced with baseline cavity modification to achieve better start-up characteristics and to enhance the low wind speed performance. The baseline cavity will provide an additional benefit of reverse drag at low TSR which is obligatory for low wind speed start-up. Numerical optimization has been carried out on the conceived airfoil NACA 0018TC-39 to find out the effective truncation percentage in terms of the chord. The numerical study has been extended to compare NACA 0018 and NACA 0018TC-39 airfoil for their aerodynamic performances in terms of lift, drag coefficients and separation characteristics. The NACA 0018TC-39 airfoil was incorporated within a non-swept straight bladed Darrieus turbine miniature to experimentally evaluate the performance in terms of dynamic power coefficient, dynamic torque coefficient and static torque coefficient and compared with conventional NACA 0018 airfoil at six different Reynolds numbers 178917, 193827, 208737, 223646, 238556 and 268376. The experimental contrast implied that NACA 0018TC-39 airfoil turbine yielded almost double power coefficients at low Reynolds number compared to conventional NACA 0018 airfoil without hampering its performance at higher Reynolds number.

Despite significant recent progress in the area of translational genomics of neuroblastoma, the overall survival rates for children with high-risk NB continue to be not more than 5 years due to tumor relapse and/or drug-resistant tumors. Herein we report on the development of a neuroblastoma targeting nanometric (130-150 nm) circulation stable liposomal system prepared from a novel nipecotic acid-derived cationic amphiphile (NACA). The size ranges of liposomes (130-150 nm) were confirmed by both dynamic light scattering and transmission electron microscopy. The findings in the gel electrophoresis assay revealed that siRNAs encapsulated within the liposomes of NACA (with 90% entrapment efficiency) are protected from attack by RNase. Cellular uptake experiments using FAM-siRNA loaded liposomes of NACA showed the liposomal entry in human neuroblastoma cells (IMR-32) to be mediated via the GABAA receptor. CDC20siRNA-loaded liposomes of NACA caused significantly higher CDC20 gene silencing efficiency in IMR-32 cells compared to CDC20 gene knockdown efficiency mediated by CDC20siRNA-loaded control non-targeting liposomes (NTL). The findings in the annexin-V binding based flow cytometric apoptosis assay and MTT-based cellular cytotoxicity assay support the notion that pronounced (80%) neuroblastoma cell death upon treatment with CDC20siRNA & PTX co-loaded liposomes of NACA presumably originates from enhanced apoptosis of cells. Importantly, intravenously administered CDC20siRNA & PTX co-loaded liposomes of NACA significantly inhibited growth of xenografted human neuroblastoma in athymic nude mice. The presently disclosed strategy of co-delivering potent anticancer siRNA and small molecule chemotherapeutics using liposomes of NACA opens a new door for combating the dreaded disease of neuroblastoma.

Force oscillations and flow around submerged objects at low Reynolds numbers are very important subjects in marine environments. On the other hand, NACA hydrofoils and circular sections are two of the most prevalent shapes that are applied in marine systems and due to the stated reason their hydrodynamic investigation becomes immensely important. Accordingly, in this paper, a flow solver has been developed based on finite volume method, and flow interactions between circular cylinders and NACA-0018 hydrofoils have been considered. For this purpose, different parametric studies have been conducted on the angles of attack and the distance of the foil from the cylinder at three different Reynolds numbers of 100, 200, and 300. Moreover, frequency of the lift and drag coefficients have been analyzed in different cases. As a result, suitable arrangements of the cylinders and foils are determined in the context of an energy conversion system where force fluctuation is helpful and flow around foils and cylinders where fluctuation of forces around them are harmful and vibration or noise propagation should be controlled.

Introduction: Oxidative stress may have detrimental effects on different structures of the cells, such as the DNA. Recently, we have published a study demonstrating that N-Acetylcysteine amide (NACA) displayed anti-inflammatory properties on the brain after exposure to oxidative stress in an established neonatal piglet model, imitating perinatal asphyxia. As different clinical studies have shown an association between the severity of hypoxic-ischemic encephalopathy and damage of the kidneys, we investigated a possible protective effect of NACA against H2O2-induced oxidative stress using a porcine epithelial-like embryonic kidney cell line (EFN-R). Objective: To investigate a potential protective effect of NACA on cells of a porcine embryonic kidney cell line exposed to H2O2. Methods: We subjected the cells to different concentrations of H2O2 for variable time periods, seeking the optimal dose-response for the experiments. Based on the results of these investigations, we exposed the cells to 100 μMol of H2O2 and/or 750 μM of NACA for 24 hours. Some of the cells would receive NACA either one hour before or one hour after exposure to H2O2. Results: The viability of the investigated EFN-R cells revealed that both, the group treated with NACA before exposure to H2O2 and the group treated with NACA after exposure to H2O2, exhibited significantly higher cell viability compared to the H2O2 group (p < 0.001 and p < 0.01, respectively). Discussion: The increased viability of the cells may indicate that NACA could play an important role in reducing oxidative stress. Taking the results from our previous study into consideration, our findings may strengthen the theory that NACA may have organ protective properties for neonates exposed to oxidative stress.

Nascent polypeptide-associated complex (NAC) is a ribosome-associated molecular chaperone which is present only in archaea and eukaryotes. The primary function of NAC is to shield the newly synthesized polypeptide chains from inappropriate interactions with the cytosolic factors. Besides that, NAC has been implicated in diverse biological functions, which suggest that it might be a multifunctional protein. An elaborate study on NAC can provide useful information on protein folding in extreme conditions in which many archaea grow. Thus, in the present study, we have studied the biophysical and the biochemical characteristics of NAC of Picrophilus torridus, an extreme thermoacidophilic archaeon. The study of protein–protein interactions and binding partners of a protein provides useful insights into the new/unreported roles of a protein. Thus, in this study, we have identified the binding partners of NAC in P. torridus. The NAC protein of P. torridus was cloned, expressed, and purified, and its binding partners were isolated by a pull down assay followed by identification with liquid chromatography–mass spectrometry. To the best of our knowledge, this is the first report on the biophysical and the biochemical characterization of NAC from P. toridus and the identification of its interacting partners.

The present study is on the experimental investigation of the flow over oscillating NACA4421 airfoils in various tandem configurations at low Reynolds number of 8.6 x 103. Force and two dimensional particle image velocimetry (PIV) measurements were carried out in the NTU closed loop water tunnel with a freestream velocity, U∞ = 0.102m/s. The effects of phase angle, ϕ, stagger distance, Sd (= x/c where x is the horizontal axial spacing between the tandem airfoils and c is the chord) and gap, G (= |y|/c, where y is the vertical spacing between the tandem airfoils) were investigated for both oscillating and static tandem airfoils. In-phase oscillating tandem configuration has shown its potential to increase average combined lift coefficient, CL up to 47.7% but resulted in a corresponding increase in average combined drag coefficient, CD up to 54% at α > ±30˚ in relation to the single oscillating case. It also attained its best combined CL / CD ratio of 2.33 which is 35% lower than the single oscillating airfoil at α = ±45˚ with Sd of 2. This is attributed to the in-phase oscillating downstream airfoil’s ability to generate 89% higher average CL than the single oscillating airfoil as a result of the down-washed vortex interaction between the primary shed vortex before its first stroke reversal. However, this interaction increases the average CD up to 5 times more than the single oscillating airfoil which decreases the combined CL / CD ratio for the in-phase oscillating tandem configuration. The out-of-phase tandem oscillating configuration produces the highest combined CL / CD ratios at larger α > ±30˚ with the larger Sd of 2.5 due to the downstream airfoil’s ability to generate large lift improvements of more than 100% and exhibiting comparable drag production in relation to the single oscillating airfoil through effectively capitalizing on its ‘indirect’ down-washed vortex interaction effects. Thus, making the out-of-phase oscillating tandem configuration at Sd = 2.5 the most ideal configuration in the present study, potentially viable for hovering flight. Doctor of Philosophy

N-acetylcysteine amide (NACA) is the amide derivative of N-acetylcysteine (NAC) that is rapidly converted to NAC after systemic administration. It has emerged as a promising thiol antioxidant for multiple indications; however, the pharmacokinetic property is yet unclear due to lack of an accurate quantification method. The present investigation aimed to develop an analytical method for simultaneous quantification of NACA and NAC in plasma. A new reagent (2-(methylsulfonyl)-5-phenyl-1,3,4-oxadiazole, MPOZ) was introduced for thiol stabilization during sample processing and storage. Further, we utilized tris (2-carboxyethyl) phosphine (TCEP) to reduce the oxidized forms of NACA and NAC. After derivatization, NACA-MPOZ and NAC-MPOZ were quantified using liquid chromatography–mass spectrometry (LC-MS). The new method was validated and found to have high specificity, linearity, accuracy, precision, and recovery for the quantification of NACA and NAC in plasma. Furthermore, the formed derivatives of NACA and NAC were stable for 48 h under different conditions. The method was utilized in pharmacokinetic study which showed that the bioavailability of NACA is significantly higher than NAC (67% and 15%, respectively). The pharmacokinetic of NACA obeyed a two-compartment open model. The glutathione (GSH)-replenishing capacity was found to be three to four-fold higher after the administration of NACA compared to that observed after the administration of NAC. In conclusion, the present method is simple, robust and reproducible, and can be utilized in both experimental and clinical studies. NACA might be considered as a prodrug for NAC. Furthermore, this is the first report describing the pharmacokinetics and bioavailability of NACA in mouse.

Wind energy as one of the new renewable energies that has considerable potential in Indonesia is known by the rapid development of wind power plants in Indonesia. The windmill blade which is one of the main components of the windmill has a role as the conversion of wind potential energy into motion energy to eventually become electrical energy that is influenced by the shape of the windmill blade of the windmill. NACA (National Aeronautical Committee Advisory) in charge of aeronautics has standards regarding varying airfoil shapes. A comparison of variations of 4-digit type airfoils (NACA 4412), 5 digits (NACA 23012) and series 16 (NACA 16-212) to determine the value of Cl / Cd from the variation of NACA airfoil types. The results of simulations carried out using Qblade software showed that the value of Cl / Cd to the highest alpha of the three types of airfoils was NACA 4412 with a value of 134, alpha 6 and the Cp value for the highest TSR was 0.44 at TSR 5.5. Furthermore, the NACA 4412 airfoil blades can be developed by making lighter material variations so that the windmill blades are easier to spin so that the resulting power becomes more maximal.

This paper investigates the unsteady flow field around the NACA 63-215 hydrofoil. Computational fluid dynamics (CFD) study is followed by tomographic particle image velocimetry (TomoPIV) experiments in a closed-loop water channel at Reynolds number of approximately 2.9 × 104. The k-ω SST turbulence model results, namely the performance metrics such as lift and drag coefficients, are within 2% of the published values in the literature. There is also a good agreement between the numerical and experimental flow filed characteristics (i.e. average total velocity) around the studied NACA 63-215 hydrofoil; a maximum difference of 2% is observed. The difference in the results is mainly from the implemented boundary condition constraints in the CFD model. Longitudinal variations of streamwise velocity (i.e. u component) deficit from CFD are within 5% of the experimental values. In contrast with 2D measurements, the TomoPIV captures the 3D phenomena such as out of the plane velocity gradients. The results from this work supports both fundamental and applied research areas such as studying the development of high-performance and cost-effective ocean current turbine array models.

The unsteady flow field in the vicinity of a NACA 63-215 hydrofoil in a closed-loop water channel at Reynolds number of Re ≈ 29103 is investigated experimentally. A Tomographic Particle Image Velocimetry (TomoPIV) is used to determine the velocity field in the near-wake region of the studied hydrofoil. The manufactured hydrofoil was mounted on the 3D traverse and installed vertically in the water tunnel test section. The TomoPIV measurement volume was performed in a voxel with the volume of 164 × 168 × 82 mm3 (X, Y, Z). Vortex identification techniques including Q-criterion and λci criterion, together with helicity of flow are evaluated in the wake of the hydrofoil. Vorticity and swirling strength are used to further understand the location and behavior of the dynamic pattern of the vortex shedding in the trailing edge of the hydrofoil. The vorticity magnitudes as they transport downstream is explored to dissipate their energy in the wake. The flow pattern reflects a turbulent behavior required for higher efficiency of the designed hydrofoil. The results are compared with literature. This work obtains a validated model for the wind farm case and will be a basis of the ocean current turbine arrays wake structure analysis.

In this study, the effect of flow suction attrailing edge on aerodynamic performance of NACA 0015 airfoil was investigated,numerically. Numerical solutions were performed by ANSYS Fluent using k-kL-ωtransition model at Reynolds number of Re=48000. Three different suction ratios(θ=0.05, 0.1 ve 0.2) were tested at four different angles of attacks (α=2°, 4°, 6° ve 8°) and obtained results were comparedwith the base case. Laminar separationbubble was controlled significantly at low angles of attack. It was observedthat CL/CD increases up to 2.4 times CL/CDof the base case with the increasing suction ratio at α=2° ve 4°. On the other hand,it was observed that the CL/CDdid not alter significantly in comparison with the base case at α=8° since CD alsoincreases while CL increases., Bu çalışmada,kanat firar kenarında uygulanan akış emme yönteminin NACA 0015 kanat profilininaerodinamik performansı üzerine etkileri sayısal çalışma ile araştırılmıştır.Sayısal çözümler Reynolds sayısının Re=48000 değerinde k-kL-ωtransition model kullanılarak ANSYS Fleunet tarafından gerçekleştirilmiştir. Üçfarklı emme oranı (θ=0.05, 0.1 ve 0.2) dört farklı kanat hücum açısında (α=2°,4°, 6° ve 8°) test edilmiştir ve elde edilen bulgular kontrolsüz durum ilekıyaslanmıştır. Düşük hücum açılarında laminer ayrılma kabarcığı önemli ölçüdekontrol edilmiştir. Hücum açılarının α=2° ve 4° değerlerinde artan emme oranıile CL/CD oranının kontrolsüz durumun 2.4 katına kadararttığı gözlemlenmiştir. Ancak hücum açısının α=8° değerinde kaldırmakatsayısının artması ile birlikte sürüklenme katsayısının da artmasından dolayıCL/CD oranının kontrolsüz duruma göre önemli ölçüdeartmadığı gözlemlenmiştir.

Traumatic brain injury resulting from exposure to blast overpressure (BOP) is associated with neuropathology including impairment of the blood-brain barrier (BBB). This study examined the effects of repeated exposure to primary BOP and post-blast treatment with an antioxidant, N-acetylcysteine amide (NACA) on the integrity of BBB. Anesthetized rats were exposed to three 110 kPa BOPs separated by 0.5 h. BBB integrity was examined in vivo via a cranial window allowing imaging of pial microcirculation by intravital microscopy. Tetramethylrhodamine isothiocyanate Dextran (TRITC-Dextran, mw = 40 kDa or 150 kDa) was injected intravenously 2.5 h after the first BOP exposure and the leakage of TRITC-Dextran from pial microvessels into the brain parenchyma was assessed. The animals were randomized into 6 groups (n = 5/group): four groups received 40 kDa TRITC-Dextran (BOP-40, sham-40, BOP-40 NACA, and sham-40 NACA), and two groups received 150 kDa TRITC-Dextran (BOP-150 and sham-150). NACA treated groups were administered NACA 2 h after the first BOP exposure. The rate of TRITC-Dextran leakage was significantly higher in BOP-40 than in sham-40 group. NACA treatment significantly reduced TRITC-Dextran leakage in BOP-40 NACA group and sham-40 NACA group presented the least amount of leakage. The rate of leakage in BOP-150 and sham-150 groups was comparable to sham-40 NACA and thus these groups were not assessed for the effects of NACA. Collectively, these data suggest that BBB integrity is compromised following BOP exposure and that NACA treatment at a single dose may significantly protect against blast-induced BBB breakdown.

Wind industry needs high quality airfoil data for a range of the angle of attack (AoA) much wider than that often provided by the technical literature, which often lacks data i.e. in deep- and post-stall region. Especially in case of vertical axis wind turbines (VAWTs), the blades operate at very large AoAs, which exceed the range of typical aviation application. In a previous study, some of the authors analyzed the trend of the lift coefficient of a NACA 0021 airfoil, using the suggestions provided by detailed CFD analyses to correct experimental data at low Reynolds numbers collected in an open-jet tunnel. In the present study, the correction method is extended in order to analyze even the drag and moment coefficients over a wide range of AoAs for two different Reynolds numbers (Re = 140k and Re = 180k) of particular interest for small wind turbines. The utility of these data is again specifically high in case of VAWTs, in which both the drag and the moment coefficient largely contribute to the torque. The investigation involves tunnel data regarding both static polars and dynamic sinusoidal pitching movements at multiple reduced frequencies. Concerning the numerical simulations, two different computational domains were considered, i.e. the full wind tunnel and the open field. Once experimental data have been purged by the influence of the wind tunnel by means of the proposed correction method, they were compared to existing data for similar Reynolds both for the NACA0021 and for similar airfoils. By doing so, some differences in the static stall angle and the extent of the hysteresis cycle are discussed. Overall, the present paper provides the scientific community with detailed analysis of low-Reynolds NACA 0021 data in multiple variations, which may enable, inter alia, a more effective VAWT design in the near future.

Potassic-jeanlouisite, ideally K(NaCa)(Mg4Ti)Si8O22O2, is the first characterised species of oxo amphibole related to the sodium–calcium group, and derives from potassic richterite via the coupled exchange CMg–1W${\rm OH}_{{\rm \ndash 2}}^{\ndash}{} ^{\rm C}{\rm Ti}_1^{{\rm 4 +}} {} ^{\rm W}\!{\rm O}_2^{2\ndash} $. The mineral and the mineral name were approved by the International Mineralogical Association Commission on New Minerals, Nomenclature and Classification, IMA2018-050. Potassic-jeanlouisite was found in a specimen of leucite which is found in the lava layers, collected in the active gravel quarry on Zirkle Mesa, Leucite Hills, Wyoming, USA. It occurs as pale yellow to colourless acicular crystals in small vugs. The empirical formula derived from electron microprobe analysis and single-crystal structure refinement is: A(K0.84Na0.16)Σ1.00B(Ca0.93Na1.02Mg0.04${\rm Mn}_{{\rm 0}{\rm. 01}}^{2 +} $)Σ2.00C(Mg3.85${\rm Fe}_{{\rm 0}{\rm. 16}}^{2 +} $Ni0.01${\rm Fe}_{{\rm 0}{\rm. 33}}^{3 +} {\rm V}_{{\rm 0}{\rm. 01}}^{3 +} $Ti0.65)Σ5.01T(Si7.76Al0.09Ti0.15)Σ8.00O22W[O1.53F0.47]Σ2.00. The holotype crystal is biaxial (–), with α = 1.674(2), β = 1.688(2), γ = 1.698(2), 2Vmeas. = 79(1)° and 2Vcalc. = 79.8°. The unit-cell parameters are a = 9.9372(10), b = 18.010(2), c = 5.2808(5) Å, β = 104.955(2)°, V = 913.1(2) Å3, Z = 2 and space group C2/m. The strongest eight reflections in the powder X-ray pattern [d values (in Å) (I) (hkl)] are: 2.703 (100) (151); 3.380 (87) (131); 2.541 (80) ($\bar 2$02); 3.151 (70) (310); 3.284 (68) (240); 8.472 (59) (110); 2.587 (52) (061); 2.945 (50) (221,$\bar 1$51).

In 2018 NACA celebrated its 50th anniversary. During this period, NACA has contributed in a significant way to promote clean air in communities around South Africa. This has not always been an easy task. The passing of the National Environmental Management: Air Quality Act in 2004 has seen a step change in air quality management. NACA provided insightful inputs to the legislation setting process, subsequent amendments and revisions as well as the implementation of this legislation

The present paper deals with the selection of blade profile for VAWTs which is to be installed in the low potential zones like central India where the mean velocity of the air is around 4 km/hr. These amplitudes are quite low for commissioning the wind turbine in that region, whereas we need around 10 km/hr speed for the installation of wind turbines. Both experimental and numerical analysis has been carried out for the three selected airfoils recommended by NASA. We are working with the three optimized profiles NACA 0012, NACA 0015 & S2027. The results show a good correlation with the existing literature. Airfoil profile S2027 has been chosen which best suits our condition.

This paper investigates the potential of modifications of the NACA 2412 aerofoil geometry which could be implemented as a morphing wing in the Cessna 172SP. A 2D study on three morphing configurations: landing, take-off and stall maneuvering was conducted. The new geometries were designed using XFLR5. The initial aerodynamics characteristics were computed using XFOIL and compared to that of NACA 2412 in the Cessna 172SP. A selected configuration (landing) was tested at the University of Brighton wind tunnel facility and comparison to XFOIL predictions. Moreover, the ESDU 07010 report was used to extrapolate the Reynold’s number to full scale, which was necessary to obtain an approximation of the aerodynamic characteristics at actual flight. The paper presents results of ANSYS FLUENT simulations for all three configurations. Results reveal that XFOIL is suitable for morphing airfoil configuration analysis but only at low Reynolds number (Re≈500,000). Adaptive aerofoil geometry improves the lift to drag (L/D) ratio by decreasing the drag coefficient; it also expands the flight envelope by delaying stall.

The wind industry needs airfoil data for ranges of angle of attack (AoA) much wider than those of aviation applications, since large portions of the blades may operate in stalled conditions for a significant part of their lives. Vertical axis wind turbines (VAWTs) are even more affected by this need, since data sets across the full incidence range of 180 deg are necessary for a correct performance prediction at different tip-speed ratios. However, the relevant technical literature lacks data in deep and poststall regions for nearly every airfoil. Within this context, the present study shows experimental and numerical results for the well-known NACA 0021 airfoil, which is often used for Darrieus VAWT design. Experimental data were obtained through dedicated wind tunnel measurements of a NACA 0021 airfoil with surface pressure taps, which provided further insight into the pressure coefficient distribution across a wide range of AoAs. The measurements were conducted at two different Reynolds numbers (Re = 140 k and Re = 180 k): each experiment was performed multiple times to ensure repeatability. Dynamic AoA changes were also investigated at multiple reduced frequencies. Moreover, dedicated unsteady numerical simulations were carried out on the same airfoil shape to reproduce both the static polars of the airfoil and some relevant dynamic AoA variation cycles tested in the experiments. The solved flow field was then exploited both to get further insight into the flow mechanisms highlighted by the wind tunnel tests and to provide correction factors to discard the influence of the experimental apparatus, making experiments representative of open-field behavior. The present study is then thought to provide the scientific community with high quality, low-Reynolds airfoil data, which may enable in the near future a more effective design of Darrieus VAWTs.

This paper presents uncertainty quantification (UQ) benchmarking activities within the NATO AVT-252 Task Group on "Stochastic Design Optimization for Naval and Aero Military Vehicles." UQ methods are assessed and compared as an essential part of stochastic optimization procedures. Several metamodel (dynamic radial basis functions, dynamic Kriging, Gaussian process), Monte Carlo (multi-level Monte Carlo) and collocation (non-intrusive stochastic collocation) methods are applied to 2D and 15D UQ problems (that is with 2 or 15 uncertainties) of a NACA 2412 airfoil subject to operational (Mach number) and geometrical (design variables) uncertainties, both in the subsonic and transonic regimes. The flow is solved by MSES, XFoil, and the FINE TM /Open suite. A pure Monte Carlo simulation based on more than 300,000 samples is used as a benchmark to assess the accuracy and efficiency of UQ methods. These can provide satisfactory results with errors for the expected value and standard deviation of C D smaller than 0.5 and 5% respectively.

In this paper NACA 2421 Aerofoil is analyzed at several angles of attack ranging from -200 to 200 and with the Reynolds number at 1.8 × 105 and the velocity are 20 m/s. The co-efficient of lift and drag are compared with the standard values in the literature. Variation of pressure co-efficient is plotted in the form of contour. The aerofoil is designed in ANSYS and it is imported to Computational Fluid Dynamics and the variations of CL and CD with respect to various angles of attack is analyzed.

Coflow-jet (CFJ) airfoil is a new type of zero-net mass flux active flow control of the airfoils. The concept was proposed by Zha et al from Miami University and presents several extraordinary aerodynamic characteristics like: super-lift coefficient, small or even negative drag coefficient and almost stall free behaviour. All these make the CFJ airfoils suitable for highly efficient airplanes including electric airplanes with distributed thrust. This paper presents an evaluation of the broadband aeroacoustic noise of a NACA 6415 CFJ airfoil and compares it with the basic NACA 6415. Numerical simulation for aerodynamic and aeroacoustic field using Navier –Stokes equations and aeroacoustic analogies are conducted with Ansys Fluent and Msc Actran solvers.

Wind energy is renewable energy and can be used as an alternative energy source. To harvest wind energy, wind turbines are used. The low power coefficient of the vertical axis wind turbine (VAWT) is one of its drawbacks. To overcome this, numerical research was carried out using a variation of the blade on NACA 0018. CFD-Fluent use in this research with turbulent model k – epsilon. The number of blades 3, 4, 5, and 6 each tested at a tip speed ratio of 1.8. The result of the simulation is plotted and discussed as contour velocity, the maximum power coefficient obtained at the number blades 5 is 0.589.

The airflow around two-dimensional standard NACA 0015 airfoil effect was studied and analysed. The study was performed by simulating three geometrical modification airfoils (bumps NACA 0015, multi-element NACA 0015, and a backward-facing step NACA0015). Using SST (Shear Stress Transport) turbulence model and compared with standard NACA 0015 was the performed methodology. The research focuses on two cases (at different attack angles from 0 to 18 degrees with Re=1.65x106). Case I: the numerical analysis method data for the coefficient of lift of standard NACA 0015 (baseline case study) is compared to the previous experimental data. Case II: the coefficient of pressure, coefficient of lift, the contour of static pressure, and the velocity contour for standard NACA 0015(chord length c=1m) were calculated and compared with three geometrical modifications NACA 0015 airfoil. The CFD software ANSYS FLUENT version 17.1 was used for the computations in the present study. As a result, the geometrical modification influences on the aerodynamic properties of NACA 0015 was investigated. Compared to standard NACA 0015 airfoil, a significant improvement in the lift coefficient for multi-element NACA 0015 was noticed especially at the angle of attack (6°,14° and 18°) while slight improvement was noticed in the lifting coefficient for the other two models (bumps NACA 0015, and a backward-facing step NACA0015) at AOA 14 degree.

Background In the breast cancer setting, anticancer therapies including doxorubicin (DOX) and trastuzumab (TRZ) are associated with a significantly increased risk of cardiotoxicity. Despite the increasing support for the role of oxidative stress (OS) in its pathophysiology, we still do not have an optimal antioxidant for the prevention of DOX + TRZ–mediated cardiac dysfunction. The objective of this study was to investigate whether the novel antioxidant N-acetylcysteine amide (NACA) can attenuate DOX + TRZ–induced heart failure in a murine model. Methods A total of 100 C57Bl/6 female mice received 1 of the following drug regimens: (1) saline, (2) NACA, (3) DOX, (4) TRZ, (5) DOX + TRZ, (6) NACA + DOX, (7) NACA + TRZ, and (8) NACA + DOX + TRZ. Serial echocardiography was performed over a 10-day study period, after which the mice were killed for histologic and biochemical analyses. Results In mice receiving DOX, the left ventricular ejection fraction (LVEF) decreased from 73% ± 4% to 43% ± 2% on day 10. In mice receiving DOX + TRZ, the LVEF decreased from 72% ± 3% to 32% ± 2% on day 10. Prophylactic administration of NACA to mice receiving DOX or DOX + TRZ was cardioprotective, with an LVEF of 62% ± 3% and 55% ± 3% on day 10, respectively. Histologic and biochemical analyses demonstrated a loss of cellular integrity, increased OS, and increased cardiac apoptosis in mice treated with DOX + TRZ, which was attenuated by the prophylactic administration of NACA. Conclusions NACA attenuated the cardiotoxic side effects of DOX + TRZ in a murine model of chemotherapy-induced cardiac dysfunction by decreasing OS and apoptosis.