Automatic Blade Shape Optimization of a Three-Bladed Modified Savonius Turbine

In this study, the performance of a new wind turbine design derived from a conventional Savonius turbine is optimized by numerical simulation. The new design consists of three blades without passage between them (closed center). The coupling between the CFD codes (ANSYS Fluent) and the optimizer (OPAL) is used through an automatic procedure in-house codes, as documented, for example, in Thévenin et al.’s Optimization and Computational Fluid Dynamics (2008). A single-objective function (output power coefficient, Cp) is considered as the target of the optimization technique and the shape of the blade as an optimization parameter and relies on evolutionary algorithms. An optimal solution can emerge from this optimization study. By comparison between regular design (semi-cylindrical shape blades) and the optimal configuration, a considerable improvement (up to 7.13% at λ = 0.7) of the optimal configuration performance can be obtained in this manner.

Prediction and investigation between impeller blade shape parameters and performance parameters in CFD and ANN

The blade shape parameters have a remarkable effect on the centrifugal pump performance. In order to reveal the relationship between these parameters and pump performance, a single channel was regarded as the research object to calculate its performance by numerical simulation, and the performance was measured on an experimental rig. The optimized ANN is proposed, and it is proved to be highly accurate. The ANN correlation coefficient of the total response could be above 0.997 after thousands of retaining. The sorts and degrees affecting performance parameters were found out by gray relation analysis. It was found that the blade angles at the leading edge were more influential for reaction force, head and minimum pressure, while the wrap angles had greater impact for efficiency. Furthermore, a multiple linear regression model was established to quantify the weight and trend of the influence of blade shape parameters on performance. The results provide a reference guide for the optimized design of centrifugal impeller to improve pump performance.

Tracheal Tube-Mounted Camera Assisted Intubation vs. Videolaryngoscopy in Expected Difficult Airway: A Prospective, Randomized Trial (VivaOP Trial)

Background: Tracheal intubation in patients with an expected difficult airway may be facilitated by videolaryngoscopy (VL). The VL viewing axis angle is specified by the blade shape and visualization of the larynx may fail if the angle does not meet anatomy of the patient. A tube with an integrated camera at its tip (VST, VivaSight-SL) may be advantageous due to its adjustable viewing axis by means of angulating an included stylet.Methods: With ethics approval, we studied the VST vs. VL in a prospective non-inferiority trial using end-tidal oxygen fractions (etO2) after intubation, first-attempt success rates (FAS), visualization assessed by the percentage of glottis opening (POGO) scale, and time to intubation (TTI) as outcome parameters.Results: In this study, 48 patients with a predicted difficult airway were randomized 1:1 to intubation with VST or VL. Concerning oxygenation, the VST was non-inferior to VL with etO2 of 0.79 ± 0.08 (95% CIs: 0.75–0.82) vs. 0.81 ± 0.06 (0.79–0.84) for the VL group, mean difference 0.02 (−0.07 to 0.02), p = 0.234. FAS was 79% for VST and 88% for VL (p = 0.449). POGO was 89 ± 21% in the VST-group and 60 ± 36% in the VL group, p = 0.002. TTI was 100 ± 57 s in the VST group and 68 ± 65 s in the VL group (p = 0.079). TTI with one attempt was 84 ± 31 s vs. 49 ± 14 s, p < 0.001.Conclusion: In patients with difficult airways, tracheal intubation with the VST is feasible without negative impact on oxygenation, improves visualization but prolongs intubation. The VST deserves further study to identify patients that might benefit from intubation with VST.

Performance optimization of liquid ring pumps based on Gappy POD surrogate model

To solve the problems of high calculation cost and difficult optimization caused by the complex gas–liquid two-phase flow in liquid ring pumps, an optimization method of a liquid ring pump impeller based on the proper orthogonal decomposition (POD) surrogate model was proposed. The impeller blade shape was parameterized by using the quartic Bezier curve. The sample was obtained from the uniform experimental design of blade shape design parameters. The POD surrogate model was constructed by the parameters of sample blade shape and its corresponding flow field data, which was used instead of CFD numerical simulation to predict the flow field variables under the perturbations of blade design parameters in the optimization process. And then, the gradient vector of the objective function to design variables was predicted quickly and accurately. The blade shape was updated continuously along the negative direction of the gradient vector, and then, the optimal design of the impeller was acquired. The calculation case results show that the relative error between the pressure field in the impeller predicted by the POD method and that of CFD simulation is less than 5%, and the calculation cost is only 1/8460 of CFD simulation. Compared with the original model, the flow field distribution in the optimized model is significantly improved, and the efficiency is promoted by 3.8%.

Aerodynamic Analysis of Novel Savonius Rotor

Wind is a renewable form of energy that holds vital solutions to energy crisis that will be faced in the possible future. Apart from the viable lift based turbines that we have been working on, research can be done on drag based turbines that can be installed in urban areas for short power requirements. The research aims at developing a novel design for Savonius type rotor which will help to improve the power producing characteristics of the turbine. CFD fluent analysis will help in analysis of the proposed blade shape. The results explain how the combination of elliptical profiled blade improves coefficient of power for Savonius type rotor. Keywords: Aerodynamics, Wind Energy, Savonius, VAWT, Wind Turbine

Impatiens bijieensis (Balsaminaceae), a new species from karst plateau in Guizhou, China

Impatiens bijieensis X.X. Bai & L.Y. Ren, a new species from Northwest Guizhou, China, is here described and illustrated. This new species is distributed discontiguously in Jiulongshan of Dafang County and Dajiucaiping of Hezhang County, both of which belong to Wumeng mountains area, a karst plateau landform. It is morphologically similar to I. lasiophyton J.D. Hooker and I. leptocaulon J.D. Hooker in height, leaf blade shape and flower form, especially resembles I. lasiophyton in pilose plant. However, it differs in its deep purplish-red to rose-red flower, 2-lobed lower sepal apex and cylindrical capsule. A detailed description, color photographs, and a provisional IUCN red list assessment are provided, and its geographical distribution, ecology, and morphological relationship with relevant similar species are discussed.

Analysis of variability of morphological characteristics of Japanese camellia varieties (Camellia japonica L.) In the conditions of protected ground of the city Moscow

In the present work, the analysis of the variability of quantitative and qualitative morphological traits of Japanese Camellia (Camellia japonica L.) varieties used in greenhouses of botanical institutions in Moscow is considered. The paper considers the following varieties: ‘Governor Mouton’, ‘Madame Lebois’, ‘Covina’, ‘Bella Toscana’, ‘Bonomiana’, ‘Alba Simplex’, ‘Lavinia Maggi’, ‘ Silver Waves ’,‘ Doncklaeri ’. To assess the variability, 10 characters were selected, six of which describe the leaf (leaf blade length, leaf blade width, leaf ovality index, leaf blade base shape, leaf blade apex shape, leaf blade shape) and four – flowers (corolla color, flower diameter, degree of terry and aroma). The variability of quantitative characteristics was assessed by determining the confidence intervals method and calculating the coefficients of variation. The variability of qualitative features was assessed by establishing modalities and determining modes. It is noted that, in terms of quantitative and qualitative characteristics, weak variability is observed in most cases. Thus, the studied varieties of Japanese camellia have stable features that characterize the flower and leaf blade. Keywords: CAMELLIA JAPONICA, JAPANESE CAMELLIA, VARIABILITY, VARIETIES