Articoli di riviste: "Continous blowing"

1

McCulloch, John G. "The History of the Development of Melt Blowing Technology". International Nonwovens Journal os-8, n. 1 (marzo 1999): 1558925099OS—80. http://dx.doi.org/10.1177/1558925099os-800123.

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Almost a half century ago development efforts were initiated by very different entities, in widely different locations, to demonstrate one step processes to convert polymer to web: • Major fiber producers (DuPont, Freudenberg, Monsanto) began work on converting polymer (PE, PET, Nylon) into continuous “cold drawn” filaments and integrating the conversion of these filaments into a random-laid bonded nonwoven fabric. • An oil company (Exxon), building on the earlier work (1950's) of the Naval Research Labs to produce fine fibers, began work on converting their recently commercialized PP polymer into discontinuous, or continuous, “hot drawn” filaments and integrating these filaments into a random-laid self bonded nonwoven web having average fiber sizes 2–5 microns (fine fibered webs) to 100+ fibers (coarse fibered webs). As a result of these early development efforts, three different, but related melt spinning nonwoven processes have achieved significant commercial importance, with tremendous benefits to consumers worldwide: • Spunbond process • Melt blowing process • Flash spinning process This presentation will summarize the development of the melt blowing process from conceptualization to current state-of-the-art. Important product, process and equipment developments are detailed in the 50 year growth of the melt blowing process from a laboratory concept to a 125 million pound a year U.S. and Canadian commercial business and substantial additional worldwide consumption. Today, spunbond and melt blown processes are used for approximately 54% of the total 18.6 million square yards U.S. nonwoven market.

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Margaris, P., e I. Gursul. "Wing tip vortex control using synthetic jets". Aeronautical Journal 110, n. 1112 (ottobre 2006): 673–81. http://dx.doi.org/10.1017/s0001924000001536.

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AbstractAn experimental investigation was conducted to study the effect of synthetic jet (oscillatory, zero net mass flow jet) blowing near the wing tip, as a means of diffusing the trailing vortex. Velocity measurements were taken, using a Particle Image Velocimetry system, around the tip and in the near wake of a rectangular wing, which was equipped with several blowing slots. The effect of the synthetic jet was compared to that of a continuous jet blowing from the same configurations. The results show that the use of synthetic jet blowing is generally beneficial in diffusing the trailing vortex and comparable to the use of continuous jet. The effect was more pronounced for the highest blowing coefficient used. The driving frequency of the jet did not generally prove to be a significant parameter. Finally, the instantaneous and the phase-locked velocity measurements helped explain the different mechanisms employed by the continuous and synthetic jets in diffusing the trailing vortex.

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Yang, Chenghao, Elias J. G. Arcondoulis, Yannian Yang, Jing Guo, Reza Maryami, Chuanxing Bi e Yu Liu. "Active control of airfoil turbulent boundary layer noise with trailing-edge blowing". Journal of the Acoustical Society of America 153, n. 4 (aprile 2023): 2115–30. http://dx.doi.org/10.1121/10.0017787.

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Large Eddy Simulation (LES) and Ffowcs Williams-Hawkings acoustic analogy are performed to study the effect of trailing-edge blowing on airfoil self-noise. Simulations were conducted using a National Advisory Committee for Aeronautics 0012 airfoil at zero angle of attack and a chord-based Reynolds number of [Formula: see text]. The aerodynamic and aeroacoustic characteristics of the baseline airfoil were thoroughly verified by comparison with previous numerical and experimental data. The noise reduction effects of continuous and local blowing with different blowing ratios and blowing momentum coefficients were compared. A maximum noise reduction of 20 dB was achieved via trailing-edge blowing and the noise reduction mechanisms of the two blowing methods were discussed. The LES results show a pair of recirculation bubbles in the airfoil wake which are suppressed by trailing-edge blowing. As the blowing vortices convect into the wake, they stretch and stabilize the shear flows from airfoil surfaces. Instantaneous vorticity and root mean square velocity fluctuations are also weakened. There is a decrease in the spanwise coherence and an increase in the phase difference, which contribute to noise reduction. It is concluded that the suppression of turbulence fluctuations in the near wake is the main mechanism of noise reduction for airfoil trailing-edge blowing.

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Li, Wenjie, Shibo Wang, Jianxin Xu, Jianhang Hu, Hua Wang, Yuling Zhai, Qingtai Xiao, Ge Deng e Dongbo Li. "Numerical Investigation of the Enhanced Stirring Characteristics of a Multi-Lance Top-Blowing Continuous Converting Furnace for Lance Arrangement and Variable-Velocity Blowing". Energies 16, n. 5 (2 marzo 2023): 2412. http://dx.doi.org/10.3390/en16052412.

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Oxygen lances are key equipment for copper converters. The effect of the lance arrangement on the mixing of a gas–slag two–phase is discussed using numerical simulation and experimental verification with a water model, and the stirring characteristics enhanced by variable–velocity blowing are explored. The results showed that the single–row lance arrangement (SA) increased the average velocity in the slag phase by 17.93% and reduced the disturbance to the metal phase by 27.78% compared to the double–row lance arrangement (DA). Compared to the constant–velocity blowing system (CSB), the sine–wave blowing system (SWB) and rectangular–wave blowing system (RWB) increased the average velocity in the slag phase by 24.03% and 13.96%, respectively, and reduced the proportion of the low–velocity area by more than 46.2%. The velocity imbalance in the SA local area enhances the mixing of the gas–slag two–phase. The variable–speed blowing improves the mass transfer and mixing effect.

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Meijie, Z., G. Huazhi, H. Ao, Z. Hongxi e D. Chengji. "Numerical simulation and industrial practice of inclusion removal from molten steel by gas bottom-blowing in continuous casting tundish". Journal of Mining and Metallurgy, Section B: Metallurgy 47, n. 2 (2011): 137–47. http://dx.doi.org/10.2298/jmmb110120006m.

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Gas blowing at the bottom of tundish is an efficient metallurgy technique in clean steelmaking. In this paper, the removal of small size inclusions in the gas bottom-blowing tundish was studied by numerical simulation and industrial practice. The residence time distribution (RTD) of molten steel in the tundish was calculated by mathematical modeling. The content of small size inclusions in the slab was analyzed using a oxygen probing and metallographic images. The results show that the molten steel characteristics obviously change when applied gas bottom-blowing, the average residence time of molten steel in the tundish prolongs more than 100s and the dead volume fraction decreases about 5%. Therefore, the removal efficiency of small size inclusions greatly increases because of bubbles attachment and long moving path. Industrial experiment results show that the average inclusions content of less than 20?m decreases more than 24%, the average overall oxygen content decreases about 15% when controlling the reasonable blowing parameters.

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Sugiura, Konosuke, e Tetsuo Ohata. "Large-scale characteristics of the distribution of blowing-snow sublimation". Annals of Glaciology 49 (2008): 11–16. http://dx.doi.org/10.3189/172756408787814960.

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AbstractTo consider the large-scale characteristics of blowing-snow sublimation and its importance in the hydrological cycle in the cryosphere, we investigated the sublimation of blowing snow particles on a global scale using the global datasets of the European Centre for Medium-RangeWeather Forecasts (ECMWF) re-analysis data and the International Satellite Land Surface Climatology Project (ISLSCP) Initiative I data for 1987. The sublimation fluxes of blowing snow particles were estimated globally with 2.5˚ resolution at 6 hour intervals. We found that the sublimation of blowing snow particles occurs more widely in the Northern Hemisphere than in the Southern Hemisphere, does not increase monotonously with latitude, and becomes more active in the polar coast regions and highlands, although the annual mean sublimation fluxes of the Northern and Southern Hemispheres are almost equal. In addition, we confirmed the characteristic seasonal changes in the area of sublimation in the Northern Hemisphere. Although we need to incorporate continuous parameters from systematic ground-based studies of the structure of blowing snow in specific fields to reduce uncertainty regarding the characteristics of blowing snow, our results point to a need to review the current understanding of the hydrological cycle.

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Ayuni, Farihah, Gina Selvia Rahayu, Nesty Ermin Nadhirah, Tegar Selaras Gustavisiana e Hisny Fajrussalam. "Perspektif Islam terhadap “Kaum Majusi” Modern". YASIN 3, n. 3 (7 maggio 2023): 342–51. http://dx.doi.org/10.58578/yasin.v3i3.1080.

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In this modern era, we often encounter celebrations by blowing out candles as part of the event. This continues to develop and grow into a culture in society. As for Islam, it strictly prohibits a celebration in which there is uproar and blowing out candles as the culmination of the event because it seems to have cultivated the habits of the former Magi. However, some other Muslims actually think that blowing out candles at a celebration is a sign of gratitude. This research is aimed at analyzing how many people cultivate candle blowing in celebrations and how Muslims view blowing candles at a celebration because this problem reaps pros and cons from Muslims themselves. The methods to be used in this research are qualitative and quantitative methods, considering the level of direct data requirement for this research.

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8

Wang, Dazhi, Fang Gao, Lidong Xing, Jianhua Chu e Yanping Bao. "Continuous Prediction Model of Carbon Content in 120 t Converter Blowing Process". Metals 12, n. 1 (14 gennaio 2022): 151. http://dx.doi.org/10.3390/met12010151.

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A continuous prediction model of carbon content of 120 t BOF is established in this paper. Based on the three-stage decarburization theory and combined with the production process of 120 t converter, the effects of oxygen lance height and top blowing oxygen flow rate are also considered in the model. The explicit finite difference method is used to realize continuous prediction of carbon content in the converter blowing process. The model parameters such as ultimate carbon content in molten pool are calculated according to the actual data of 120 t BOF, which improves the hit rate of the model. Process verification and end-point verification for the continuous prediction model have been carried out, and the results of process verification indicate that the continuous prediction model established in the paper basically accords with the actual behavior of decarburization. Moreover, the hit ratio of the continuous prediction model reached 85% for the prediction of end-point carbon content within a tolerance of ±0.02%.

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9

Yoshinaga, Etsuo. "Blow Analytic Mappings and Functions". Canadian Mathematical Bulletin 36, n. 4 (1 dicembre 1993): 497–506. http://dx.doi.org/10.4153/cmb-1993-065-1.

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AbstractLet π: M —> Rn be the blowing-up of Rn at the origin. Then a continuous map-germ f: (Rn — 0,0) —> Rm is called blow analytic if there exists an analytic map-germ such that Then an inverse mapping theorem for blow analytic mappings as a generalization of classical theorem is shown. And the following is shown. Theorem: The analytic family of blow analytic functions with isolated singularities admits an analytic trivialization after blowing-up.

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10

Zhang, M. J., H. Z. Gu, A. Huang, H. X. Zhu e C. J. Deng. "Physical and mathematical modeling of inclusion removal with gas bottom-blowing in continuous casting tundish". Journal of Mining and Metallurgy, Section B: Metallurgy 47, n. 1 (2011): 37–44. http://dx.doi.org/10.2298/jmmb1101037z.

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Gas blowing at the bottom of tundish is an efficient metallurgy technique in clean steelmaking and has been widely concerned. In this paper, spherical alumina particles were selected to model inclusions, 1:3 scale model was utilized, the removal efficiency of inclusions with the gas bottomblowing in the tundish was studied by physical and mathematical modeling. The mathematical model is validated by comparing the predicted and measured residence time distributions and dye flow patterns of tracer. The results show that while the removal efficiency of large size particles has no obvious changes, the gas bottom-blowing has great contribution to the removal of small particles.

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Yamaguchi, Gaku, Hiroyuki Miura, Eiji Nakajima e Norihiko Ikeda. "Head-down tilt position successfully prevent severe brain air embolism". SAGE Open Medical Case Reports 6 (gennaio 2018): 2050313X1880926. http://dx.doi.org/10.1177/2050313x18809265.

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Air embolisms are rare life-threatening complications that develop under various conditions, including surgery. During segmentectomy for thoracic surgery, air is blown into the selected bronchus for segment margin detection. This may result in the formation of an air embolus. Herein, we report a case of successful recovery from sudden intraoperative cardiac arrest due to an air embolism in a patient undergoing left superior division segmentectomy via open thoracotomy. Intraoperatively, the patient was positioned head-down. Upon blowing air into the bronchus, the patient suddenly developed cardiac arrest. Open-chest cardiac massage and low-temperature therapy were commenced and the patient recovered. The head-down position prevents the air embolus from reaching the brain and thus prevents severe brain damage, whereas continuous open-chest massage and low temperature prevents severe body damage from anticipated cardiac air embolism. Thus, operation in the head-down position is useful in preventing severe brain damage from brain air embolisms.

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12

Jackson, Richard, Zhijin Wang e Ismet Gursul. "Control of Upswept Afterbody Vortices Using Continuous and Pulsed Blowing". Journal of Aircraft 57, n. 1 (gennaio 2020): 76–92. http://dx.doi.org/10.2514/1.c035639.

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13

Chono, Shigeomi, Yoshiyuki Iemoto e Takashi Terachi. "Model experiment on interlaced yarn. Part 5: Continuous blowing method." Sen'i Kikai Gakkaishi (Journal of the Textile Machinery Society of Japan) 43, n. 7 (1990): T53—T61. http://dx.doi.org/10.4188/transjtmsj.43.7_t53.

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14

Fichou, Goulwen, Jean-Philippe Monnier e Ronan Quarez. "Continuous functions on the plane regular after one blowing-up". Mathematische Zeitschrift 285, n. 1-2 (1 giugno 2016): 287–323. http://dx.doi.org/10.1007/s00209-016-1708-8.

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Baek, Soo-Whang, e Sang Wook Lee. "Aerodynamic drag reduction on a realistic vehicle using continuous blowing". Microsystem Technologies 26, n. 1 (22 febbraio 2019): 11–23. http://dx.doi.org/10.1007/s00542-019-04355-w.

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Coulthard, Sarah M., Ralph J. Volino e Karen A. Flack. "Effect of Jet Pulsing on Film Cooling—Part II: Heat Transfer Results". Journal of Turbomachinery 129, n. 2 (31 maggio 2006): 247–57. http://dx.doi.org/10.1115/1.2437230.

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Pulsed film cooling was studied experimentally to determine its effect on film-cooling effectiveness and heat transfer. The film-cooling jets were pulsed using solenoid valves in the supply air line. Cases with a single row of cylindrical film-cooling holes inclined at 35 deg to the surface of a flat plate were considered at blowing ratios of 0.25, 0.5, 1.0, and 1.5 for a variety of pulsing frequencies and duty cycles. Temperature measurements were made using an infrared camera and thermocouples. The plate was equipped with constant flux surface heaters, and data were acquired for each flow condition with the plate both heated and unheated. The local film-cooling effectiveness, Stanton numbers, and heat flux ratios were calculated and compared to baseline cases with continuous blowing and no blowing. Stanton number signatures on the surface provided evidence of flow structures, including horseshoe vortices wrapping around the film-cooling jets and vortices within the jets. Pulsing tends to increase Stanton numbers, and the effect tends to increase with pulsing frequency and duty cycle. Some exceptions were observed, however, at the highest frequencies tested. Overall heat flux ratios also show that pulsing tends to have a detrimental effect with some exceptions at the highest frequencies. The best overall film cooling was achieved with continuous jets and a blowing ratio of 0.5. The present results may prove useful for understanding film-cooling behavior in engines, where mainflow unsteadiness causes film-cooling jet pulsation.

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Xiao, Shi Cheng, L. P. Zhang, Li Yong Ni, Wen Hua Yang e H. L. Liu. "Comparison of Stretching with Horizontal V-Shaped Anvils and Common Flat Anvils". Materials Science Forum 628-629 (agosto 2009): 611–16. http://dx.doi.org/10.4028/www.scientific.net/msf.628-629.611.

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Research was conducted for stretching with horizontal V-shaped anvils (HVA) and common flat anvils (FA). The forgoing research gave the simulation results of single blowing during stretching, and did not pay attention to the influence of the deformation, resulting from the previous blowing, upon the next blowing. ANSYS software is adopted to simulate the through-continuous blowing of HVA and FA forging methods. The transversal stress distribution along the horizontal central axis on the crosssection of the stretched forging is analyzed. The simulation results show that during the stretching with flat anvils, when the ratio of the flat anvil width to the billet height is 1.0 and the ratio of the billet width to the billet height is 0.5, the transversal stress is tensile all the time, and increases as the stretching goes. On the contrary, during the HVA stretching, the stress is compressive and its absolute value increases gradually. The results show that the HVA stretching method is prior to the FA stretching method in the controlling of transversal stress. Conducted physical experiment verified the results.

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Singh, S. N., S. B. Burns, J. S. Costa e V. Bonapersona. "Method of Increasing the Solubility of Hydrocarbons and HFCs in Polyurethanes Raw Materials and the Effects on the Performance and Processing Characteristics of Construction Foams*". Cellular Polymers 16, n. 6 (novembre 1997): 1–24. http://dx.doi.org/10.1177/0262489319971606004.

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Liquid hydrocarbons and hydrofluorocarbons (HFCs) are the leading zero ozone depletion potential (ODP) blowing agents being considered for rigid polyurethane foam insulation used in the construction industry. Different isomers of pentane, namely normal-, iso- and cyclopentane, are the major hydrocarbons under consideration. The leading HFCs being evaluated are HFC-245fa (CF3-CH0-CF9H) and HFC-365mfc (CF3-CH2-CF2-CH3). The solubility of such blowing agents in many of the typical polyols and isocyanates used by the construction industry is limited. Additives have been used to improve the solubility of blowing agents in the past. For example, ethoxylated nonylphenol was added to many polyols in order to enhance CFC-11 (CCI3F) compatibility. A great many additives are being proposed today for use with hydrocarbons and HFCs. This study examines the fundamental properties of various hydrohalocarbon and hydrocarbon blowing agents, and their relationship to solubility in polyurethane raw materials. The solubility of the various pentane isomers in many polyols and isocyanates used to produce insulation boardstock in a continuous lamination process is evaluated. The potential of many isocyanate modifications and polyol additives to improve blowing agent solubility is explored. The effects of blowing agent solubility on the processing characteristics of foam properties are also examined. The data is used to examine the conventional theory regarding soluble systems - are such systems always necessary to get good processing? Many non-reactive or monofunctional additives that improve solubility are found to affect the structural, thermal or flammability performance of resulting foams. This paper presents data on potential methods to obtain robust processing and good perfonnance with the zero ODP blowing agents being considered by the rigid foam industry.

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Li, Yang, Changgui Cheng, Minglei Yang, Zhixuan Dong e Zhengliang Xue. "Behavior Characteristics of Argon Bubbles on Inner Surface of Upper Tundish Nozzle during Argon Blowing Process". Metals 8, n. 8 (30 luglio 2018): 590. http://dx.doi.org/10.3390/met8080590.

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During continuous casting of aluminum-killed steel, clogging of tundish nozzle frequently occurs, which seriously disrupts the normal casting sequences and deteriorates strand quality. Generally, argon blowing technology in the form of a stable and continuous argon film on the inner surface of the upper nozzle is employed to prevent the upper nozzle from clogging in the production. To explore the formation mechanism and influence factors of this argon film, a water model of the upper nozzle with blowing argon with a similarity ratio of 1:1 was built. The results show that the number of bubble chains increases gradually with increasing argon flow rate and casting speed, and the argon gas curtain appears at the bottom half of the upper nozzle. For a given argon flow rate, the velocity of argon gas bubbles increased gradually with increasing casting speed, and decreased gradually with increasing distance from the upper nozzle top. For a given casting speed, the average velocity of argon gas bubbles was largest at a distance from the upper nozzle top of 6 mm with argon flow rate of 150 L/h. The results could provide theoretical and technical basis for the optimization of blowing argon parameters in order to prevent the clogging of upper nozzle and improve strand quality.

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Dong, Kai, e Xueliang Wang. "CO2 Utilization in the Ironmaking and Steelmaking Process". Metals 9, n. 3 (28 febbraio 2019): 273. http://dx.doi.org/10.3390/met9030273.

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Study on the resource utilization of CO2 is important for the reduction of CO2 emissions to cope with global warming and bring a beneficial metallurgical effect. In this paper, research on CO2 utilization in the sintering, blast furnace, converter, secondary refining, continuous casting, and smelting processes of stainless steel in recent years in China is carried out. Based on the foreign and domestic research and application status, the feasibility and metallurgical effects of CO2 utilization in the ferrous metallurgy process are analyzed. New techniques are shown, such as (1) flue gas circulating sintering, (2) blowing CO2 through a blast furnace tuyere and using CO2 as a pulverized coal carrier gas, (3) top and bottom blowing of CO2 in the converter, (4) ladle furnace and electric arc furnace bottom blowing of CO2, (5) CO2 as a continuous casting shielding gas, (6) CO2 for stainless steel smelting, and (7) CO2 circulation combustion. The prospects of CO2 application in the ferrous metallurgy process are widespread, and the quantity of CO2 utilization is expected to be more than 100 kg per ton of steel, although the large-scale industrial utilization of CO2 emissions is just beginning. It will facilitate the progress of metallurgical technology effectively and promote the energy conservation of the metallurgical industry strongly.

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Coulthard, Sarah M., Ralph J. Volino e Karen A. Flack. "Effect of Jet Pulsing on Film Cooling—Part I: Effectiveness and Flow-Field Temperature Results". Journal of Turbomachinery 129, n. 2 (31 maggio 2006): 232–46. http://dx.doi.org/10.1115/1.2437231.

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Abstract (sommario):

Pulsed film cooling was studied experimentally to determine its effect on film-cooling effectiveness. The film-cooling jets were pulsed using solenoid valves in the supply air line. Cases with a single row of cylindrical film-cooling holes inclined at 35 deg to the surface of a flat plate were considered at blowing ratios of 0.25, 0.5, 1.0, and 1.5 for a variety of pulsing frequencies and duty cycles. Temperature measurements were made using an infrared camera, thermocouples, and cold-wire anemometry. Hot-wire anemometry was used for velocity measurements. The local film-cooling effectiveness was calculated based on the measured temperatures, and the results were compared to baseline cases with continuous blowing. Phase-locked flow temperature fields were determined from cold-wire surveys. Pulsing at high frequencies helped to improve film-cooling effectiveness in some cases by reducing overall jet liftoff. At lower frequencies, pulsing tended to have the opposite effect. With the present geometry and a steady mainflow, pulsing did not provide an overall benefit. The highest overall effectiveness was achieved with continuous jets and a blowing ratio of 0.5. The present results may prove useful for understanding film-cooling behavior in engines, where mainflow unsteadiness causes film-cooling jet pulsation.

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Moore, Robert E. "Refractories: Something Old and Something New". MRS Bulletin 14, n. 11 (novembre 1989): 34–37. http://dx.doi.org/10.1557/s0883769400061182.

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The earliest refractories for containing melts were quarried from natural deposits of limestone and dolomite. Today these two carbonate rocks serve important roles in the production of metal contact refractories. Early refractories for glass melting on the other hand were manufactured from clays and claystones. These materials are also still used extensively for the batch melting of glasses that are hand formed or blown into art and tableware. Glass contact refractories for the continuous (tank) melting of glass are often fired, cast into large shapes, and arranged in a soldier course which constitutes the sidewalls of the glass tank.In this brief exposition of refractories technology and allied research, the articles by B. Brezny, T.F. Vazza and T.A. Leitzel, and by T.S. Busby cover materials development, selection, and properties of the systems which have evolved for the efficient melting of steels and glasses. As such they relate to extremes of technological flux in the processes for the manufacture of steel and glass, respectively.The continuous melting of large volumes of commercial glasses has been carried out in tanks equipped with reverberators for at least 70 years. The basic design of the overall system and of many of the glass fabrication machines for pressing, rolling, and blowing the glass has been constant since World War I. Only the introduction of the float glass method, the famous Pilkington process, for the production of flat glass, has interrupted the slow quiet progress in the technology of continuous glass making.

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Turpin, Aaron M., Daniel Chin e Kenneth Granlund. "Supersonic Cavity Flow Subjected to Continuous and Transient Leading-Edge Blowing". AIAA Journal 58, n. 10 (ottobre 2020): 4415–25. http://dx.doi.org/10.2514/1.j059267.

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Fiorot, Jean-Charles, e Olivier Gibaru. "Blowing-up method. Application to G2-continuous filling surfaces in CAD". Comptes Rendus de l'Académie des Sciences - Series I - Mathematics 330, n. 7 (aprile 2000): 623–28. http://dx.doi.org/10.1016/s0764-4442(00)00231-7.

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Chen, Cha'o-Kuang, e Ming-I. Char. "Heat transfer of a continuous, stretching surface with suction or blowing". Journal of Mathematical Analysis and Applications 135, n. 2 (novembre 1988): 568–80. http://dx.doi.org/10.1016/0022-247x(88)90172-2.

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Fiorot, Jean-Charles, e Olivier Gibaru. "Blowing up: application to $G^2$ -continuous 8-sided filling patch". Numerische Mathematik 92, n. 2 (1 agosto 2002): 257–87. http://dx.doi.org/10.1007/s002110100366.

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Kayser, John C., e Robert L. Shambaugh. "The manufacture of continuous polymeric filaments by the melt-blowing process". Polymer Engineering and Science 30, n. 19 (ottobre 1990): 1237–51. http://dx.doi.org/10.1002/pen.760301908.

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Fransson, J. H. M., P. Konieczny e P. H. Alfredsson. "Flow around a porous cylinder subject to continuous suction or blowing". Journal of Fluids and Structures 19, n. 8 (novembre 2004): 1031–48. http://dx.doi.org/10.1016/j.jfluidstructs.2004.06.005.

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Liang, Xu, Zhang Ge e Wang Bo. "Application of Oxygen-enriched Side-blowing Technology in Treating Zinc Leaching Residue in China". Journal of Physics: Conference Series 2738, n. 1 (1 aprile 2024): 012023. http://dx.doi.org/10.1088/1742-6596/2738/1/012023.

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Abstract Zinc hydrometallurgy is the main process of zinc smelting in the world. The leaching residue produced by different hydrometallurgical processes have different components, but they contain valuable metals such as zinc, silver, gold, indium and germanium, and heavy metals such as lead, cadmium and arsenic. In China, leaching residue is defined as hazardous waste, which requires harmless treatment and recovery of valuable metals. At present, China’s main zinc leaching residue treatment technologies include Welz kiln, fuming furnace and Top-submerged lance Smelting furnace. These technologies have been applied for many years and are mature and reliable, but they need further improvement in energy conservation and environmental protection. In recent years, with the continuous progress of China’s smelting technology, the oxygen-enriched side-blowing technology has been successfully applied to the treatment of zinc leaching residue, mainly including the Side-submerged combustion smelting technology of China ENFI and the Vanukov side-blowing technology. At present, the above two side blowing technologies have been put into industrial practice in many zinc smelters in China, which are characterized by low energy consumption, high recovery rate of valuable metals and high sulfur recovery rate. This paper introduces the application of the above two side blowing technologies in China’s zinc smelters, and compares them from furnace structure, production operation, and technical indicators. Oxygen-enriched side-blowing technology will become the mainstream treatment process of zinc residue in China and even in the world in the future.

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Li, Canyang, Wenkai Fu e Xi Meng. "A Contrast Experiment on the Ventilation Direction towards Human Head in Personalized Environmental Control System (PECS)". Sustainability 16, n. 13 (3 luglio 2024): 5704. http://dx.doi.org/10.3390/su16135704.

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A heating, ventilation, and air-conditioning system is designed for the entire space but falls short in meeting diverse individual needs. Therefore, the personalized environmental control system is proposed to address individual thermal requirements and it has been widely accepted and produced to have significant practical value for humans. In order to enhance the comfort level based on the PECS, the impact of the airflow direction towards the head in terms of physiological and psychological sensations was investigated. Different airflow directions were considered as follows: front blowing (FB-PV), side blowing (SB-PV), back blowing (BB-PV), top blowing (TB-PV), and a control group No-PV. A total of 56 participants were invited to assess the thermal environment, and their skin temperature was measured. The results revealed that the airflow towards the head improved thermal comfort and reduced the mean skin temperature by 0.4–0.6 °C, with FB-PV showing particularly promising results. TB-PV demonstrated the highest level of comfort with a score of +1.05 (slightly higher than “Just comfortable (+1)”) and scored significantly higher in overall willingness at +1.21 (higher than “Willing (+1)”). Conversely, FB-PV resulted in a discomfort level due to restricted breathing under the continuous airflow condition.

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31

Mammadov, Arif, Aqil Babayev, Nizami Ismayilov, Muxtar Huseynov e Faiq Guliyev. "Improvement of Production Processes of Seamless Steel Pipes for Oil and Gas Production". Key Engineering Materials 979 (5 aprile 2024): 63–71. http://dx.doi.org/10.4028/p-i7keoa.

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The article discusses the features of improving the technological processes of electric smelting, out-of-furnace processing, continuous casting and heat treatment of steel pipe blanks used for oil and gas production. To this end, ways to improve steel processing processes in electric furnaces and non-furnaces were shown, processes for the production of continuous casting pipes with special properties for oil and gas production were studied, the design of an alloying-refining lance (LRF) was developed, refining processes by blowing magnesium-based powders were studied, heat treatment modes for continuously cast billets during pressure treatment of pipe billets have been developed. The conducted research created the basis for the development of measures to organize the production of high-quality pipes for oil and gas production in the conditions of Baku Steel Company LLC. It has been established that blowing liquid steel with inert gases (for example, argon) in an intermediate furnace or treating it with a special composition of synthetic slag, the use of LRF in an electric furnace, the correct setting of the cooling system on a continuous casting machine (CCM), the use of a vacuum system on a continuous caster, the process of refining steel by blowing Powders based on magnesium oxide instead of lime are considered more effective means of improving the quality of steel. Based on the application of these measures, low-carbon low-alloy steel 13HFA was developed and seamless pipes with a ferrite-pearlite structure were obtained from it using continuous casting technology. The strength characteristics of this steel after casting and heat treatment fully comply with the requirements of the European standard. After heat treatment (hardening and high-temperature tempering), the surface of the pipes becomes harder (troostite + sorbitol), and the core has a soft, i.e., viscous (perlite + sorbitol) structure. This “layered” structure allows the pipes to operate successfully in difficult oil and gas production conditions.

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32

Djojodihardjo, Harijono. "Overview of Coănda Jet and Vortex Cell Circulation Control". Applied Mechanics and Materials 564 (giugno 2014): 118–25. http://dx.doi.org/10.4028/www.scientific.net/amm.564.118.

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Abstract (sommario):

Flow control for enhanced aerodynamic performance have been utilized for enhanced lift, reduced drag and delay of stall at higher angle of attack. To this end, techniques such as continuous, synthetic and pulsed jets, compliant surface, vortex-cell, Coănda jet and the like have been developed and applied to alter the behavior of airfoils, wings, and bodies and other aerodynamic components. Two such techniques are here assessed as potentially promising technique in the framework of airfoil surface blowing circulation enhancement, i.e. Coănda-jet circulation enhancement and vortex-cell. Their progress and development in influencing the effectiveness and configuration of airfoil surface blowing for circulation enhancement of aerodynamic surfaces are discussed, using fundamental principles and CFD technique.

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33

Tong, Xinting, Xiaohui Zhang, Rui Feng, Jinhu Lin e Hua Wang. "Numerical simulation of continuous bubbles motion behavior with different lance spacings". Thermal Science, n. 00 (2022): 204. http://dx.doi.org/10.2298/tsci220813204t.

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The lance is a critical component of the bottom-blowing pool melting process, and its placement has an important impact on the pool?s gas-liquid two-phase flow. In this study, a mathematical model of the bottom-blowing process is established, and the flow pattern, trajectory, wake vortex, and velocity of bubbles under four lance spacings are simulated. Results show that there are three basic bubble flow patterns appear in the flow field: bubbles coalesce before leaving the nozzle (Pattern I), bubbles coalesce after leaving the nozzle (Pattern II), and no coalescence during the rise of bubbles (Pattern III). The bubble pattern varies from Pattern I to Pattern III with the increase in lance spacing. The intensity of the influence of the wake vortex on the bubbles decreases. The Q (The Q is the second Galilean invariant of the velocity gradient tensor ?v.) value of the wake vortex is small, but the vortex structural distribution is complex. Moreover, there is a large velocity difference between gas and liquid at the beginning of gas injection, but the velocity difference between them decreases after gas injection, so the average turbulent kinetic energy in the pool initially increases sharply, and then approaches dynamic equilibrium. The top and bottom velocities of the bubbles are consistent, and the velocity fluctuation is orderly. Moreover, the greater the lance spacing is, the greater the disturbance in the pool is. The mixing effect of D = 0.2 m is the best among the four spacings.

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34

Alter, M. A., O. L. Chaika, B. V. Kornilov e A. O. Moskalyna. "Analysis of the development of blast furnace blowing technologies in the 20th and 21st centuries". Fundamental and applied problems of ferrous metallurgy 37 (2023): 26. http://dx.doi.org/10.52150/2522-9117-2023-37-26-49.

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The article discusses the trends and classification of blast furnace blowers over the past 100 years. The development of blower technology is divided into 3 periods: The 1st period lasted until the end of the 30s of the XX century, characterized by a lack of scientific knowledge, mysticism and based on previous experience; the 2nd period - until the early 70s, when the "traditional" blower technology was mastered with one problem - difficulties with opening the first releases and simultaneous overheating of the top; the 3rd period continues today, it includes the development of new methods for intensifying heat transfer during blowing and scientific generalization of blower techniques. The main tasks of blowdown are to bring the blast furnace back to normal operation in a short time, in compliance with safety rules, without significant costs, and to preserve the blast furnace and auxiliary equipment for long-term productive operation. These tasks are closely linked to the design features of blast furnaces, including the cooling system, lining type and furnace size, which have steadily increased from less than 500 m3 to 5,600 m3. The complexity of understanding the processes of heating the charge column during the blowing period with the formation of a gas flow and a cohesion zone in it is the reason for numerous discussions about rational blowing methods: methods for calculating and placing layers of the blast furnace charge, the use of various hot blast additives (nitrogen, natural, blast furnace or coke oven gas, oxygen, steam, etc.), the rate of increase in hot blast flow and its temperature, the trend of pressure drop along the height of the charge column. The use of wood in the blast charge, the installation of constrictor rings in air tuyeres or the closure of a part of the tuyeres for blowing are discussed. Recommendations for blast furnace blowers are given. A comparison of "traditional" blowing with "progressive" blowing and blowing with nitrogen developed at the Iron and Steel Institute National Academy of Sciences of Ukraine are presented.

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35

Tung Pham Duy, Tomoaki Watanabe e Koji Nagata. "LES Investigation of a Piston-driven Synthetic Jet Actuator with Multiple Orifices". CFD Letters 16, n. 1 (29 novembre 2023): 150–70. http://dx.doi.org/10.37934/cfdl.16.1.150170.

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Abstract (sommario):

A piston-driven synthetic jet actuator has the potential for application in flow control and fundamental studies of turbulence, although the high-speed flow generated by this actuator is less investigated than a low-speed synthetic jet. The interaction of high-speed jets issued from a piston-driven synthetic jet actuator with multiple orifices is investigated with large eddy simulation (LES). The maximum jet Mach number is related to the maximum pressure inside the actuator regardless of the number of orifices. Temporal variations of the jet Mach number are almost identical for different cycles, and the jet formation in each cycle occurs under the same conditions despite the unsteady nature of the jet interaction. The phase-averaged statistics are used to examine the interaction of the synthetic jets. The converging, merging, and combined regions known for the interaction of continuous jets appear for the interaction of the high-speed synthetic jets slightly before the end of the blowing phase. However, the converging region is not clearly observed at the beginning of the blowing phase because the jets tend to be parallel to each other. Therefore, the combined region forms at a late stage of the blowing phase. Before the jets are combined, velocity fluctuations in the blowing phase become large near the furthest locations where the jets reach. Once the jets merge by their interaction, large velocity fluctuations are observed at the downstream end of the merging region. The probability density functions of velocity fluctuations in the blowing phase tend to deviate from a Gaussian distribution along the centerline of the jets. This deviation is more significant for the two-orifice model than for the four-orifice model under the same actuation frequency.

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36

Ivdre, Aiga, Anda Fridrihsone-Girone, Arnis Abolins e Ugis Cabulis. "Effect of different concentration of rapeseed oil and recycled poly (ethylene terephthalate) in polyols for rigid polyurethane foams". Journal of Cellular Plastics 54, n. 2 (23 settembre 2016): 161–77. http://dx.doi.org/10.1177/0021955x16670585.

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Abstract (sommario):

In this research, polyols from rapeseed oil and recycled poly(ethylene terephthalate) were synthesized by two-step continuous synthesis with a different rapeseed oil and poly(ethylene terephthalate) concentration. All rapeseed oil/poly(ethylene terephthalate) polyols showed complete compatibility with blowing agent Solkane 365/227. The resulting polyols were used to prepare rigid polyurethane foams which were characterized with various techniques for determination of their physical, mechanical and thermal insulation properties. The effect of rapeseed oil and poly(ethylene terephthalate) concentrations in polyols on the characteristics of rigid polyurethane foams was investigated. The results showed that obtained rigid polyurethane foams were suitable for thermal insulation appliance. Also, the potential use of rapeseed oil as raw material combined with poly(ethylene terephthalate) to synthesize polyols with good compatibility with blowing agent was confirmed.

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37

Gaponov, Sergey, e Natalya Terekhova. "The Combined Influence Of Heat And Mass Transfer Through A Porous Wall On The Boundary Layer Stability Compressible Gas At High Mach Numbers". Siberian Journal of Physics 10, n. 3 (1 ottobre 2015): 31–40. http://dx.doi.org/10.54362/1818-7919-2015-10-3-31-40.

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This work continues the research on modeling the management regime in the boundary layer of compressible gas. The effect of the distribution of heat and mass transfer on the stability characteristics of supersonic boundary layer at high supersonic Mach number M = 5,35. The focus is on the modeling of acoustic disturbances in the conditions as a normal injection, in which the only nonzero component of the average velocity V, and the injection of other areas, including tangential, when the wall is not zero only U component. Production close to the problem of influence on the development of gas curtain small oscillations. It is assumed that the effect of injection of a homogeneous gas of different temperature similar to that of the blowing gas of different density, namely, blowing cold gas simulates heavy gas blowing and vice versa. Therefore in this modeling work is achieved by changing the factor of temperature (heating or cooling of the walls). The variant when the socalled regime implemented «lock» when the velocity perturbations on the porous surface can be taken as zero.

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38

Zhao, Yutang, Xiaohui Zhang, Xinting Tong, Xiaolv Yu, Jing Luo, Yanxiong Fu e Hua Wang. "The motion and wake characteristics of bottom blowing coaxial double bubbles". Thermal Science, n. 00 (2024): 92. http://dx.doi.org/10.2298/tsci231208092z.

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In the process of bottom blowing bath smelting, continuous bubbles are formed and rise in the melt after the bottom blowing gas is ejected. In order to reveal the motion behavior and wake characteristics of continuous bubbles formed during the injection process, the rising process of coaxial double bubbles is studied through numerical simulation, the velocity and deformation characteristics of coaxial double bubbles in the rising process are obtained. Based on the vortex identification reconstruction of the flow field, the characteristics of formation, evolution, and configuration of bubble wake are obtained. The results show that in terms of motion characteristics, the aspect ratio of the upper bubble is always less than 1, and lower bubble has a large span of change: The minimum is 0.85 and the maximum is 1.2. As the two bubbles approach, the aspect ratio of the upper bubble is always less than 1, while the maximum aspect ratio of the lower bubble can reach 1.2. In terms of wake characteristics, the vorticity on the upper bubble surface is larger. When the wake rotation centers of the upper and lower bubbles merge with each other, the instantaneous acceleration of the lower bubble reaches the maximum.

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39

Tachimura, Takashi, Kanji Nohara, Koichi Satoh e Takeshi Wada. "Evaluation of Fatigability of the Levator Veli Palatini Muscle during Continuous Blowing Using Power Spectra Analysis". Cleft Palate-Craniofacial Journal 41, n. 3 (maggio 2004): 320–26. http://dx.doi.org/10.1597/02-038.1.

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Objective The purpose of this study was to compare the fatigability of the levator veli palatini (LVP) muscle during blowing in speakers who exhibit velopharyngeal incompetence with that from normal speakers by means of power spectra analysis. Design All subjects were instructed to blow into a tube for more than 10 seconds at maximum possible effort. The LVP muscle activity (electromyography) was sampled at 2 kHz for 10 seconds from the time when the oral air pressure during blowing was stabilized. These samples were subjected to Fast Fourier Transfer analysis with analytic windows of 0.5-second width. The electromyography mean power frequency slope with respect to time for each subject was estimated. Participants Three speakers with repaired cleft palate and three normal speakers were selected as subjects. Results The slopes of the regression lines for all three subjects with repaired cleft palate were negatively signed with statistical significance (t test, p < .01). The slopes for all of the normal speakers were negatively signed, but these were not statistically significant. Conclusion These results suggest that the LVP muscle of speakers with repaired cleft palate who exhibit varying degrees of velopharyngeal dysfunction may deteriorate more easily in comparison with the LVP muscle of normal speakers.

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40

Xu, Guojie, Bei Zhou, Jian Guo, Jun Zeng, Rongguang Zhang, Nian Cai, Yongxing Li et al. "Research on the Mechanism of Multi-Domain Coupling Centrifugal Electrostatic Blowing Flying Deposition". Micromachines 13, n. 9 (24 agosto 2022): 1378. http://dx.doi.org/10.3390/mi13091378.

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The centrifugal electrostatic blowing process proposed in this paper solves the difficult continuous and stable deposition problem in the traditional centrifugal electrostatic spinning process. By establishing a flight deposition model of the centrifugal electrostatic spraying process, CFD is used to simulate and analyze the electrohydrodynamic effect of centrifugal jets, and the driving mechanism is explored. Subsequently, MATLAB is used to obtain the optimal solution conditions, and finally, the establishment of a two-dimensional flight trajectory model is completed and experimentally verified. In addition, the deposition model of the jet is established to clarify the flight trajectory under the multi-field coupling, the stable draft area of the jet is found according to this, and the optimal drafting station is clarified. This research provides new ideas and references for the exploration of the deposition mechanism of the centrifugal electrostatic blowing and electrostatic spinning process.

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41

Wang, Wentao, Hui Zhang, Yangyong Dai, Hanxue Hou e Haizhou Dong. "Effects of low poly(vinyl alcohol) content on properties of biodegradable blowing films based on two modified starches". Journal of Thermoplastic Composite Materials 30, n. 7 (28 ottobre 2015): 1017–30. http://dx.doi.org/10.1177/0892705715614080.

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Biodegradable films from hydroxypropyl distarch phosphate (HPDSP)/poly(vinyl alcohol) (PVA) and cationic starch/PVA blends were obtained by extrusion blowing at ratios of 100:0, 95:5, 90:10, 85:15, and 80:20. The morphology, X-ray patterns, transparency, mechanical properties, thermal properties, and water vapor permeability (WVP) of the films were measured and compared. Scanning electron microscopic micrographs of the films showed continuous matrix texture as well as better compatibility between modified starches and PVA. X-Ray diffraction indicated the formation of ordered crystalline structures in the films during extrusion blowing. The addition of PVA to modified starches significantly increased their tensile strength (TS, 3.92 MPa) while decreasing their water vapor permeability (WVP, 3.23 × 10−10 g m−1 s−1 Pa−1). The starch/PVA composite films did not show phase separation.

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42

Zhou, Jie Min, Qiang Gao, Liu Liu, Fang Kan Liu e Hong Jie Yan. "Fluid-Flow Characteristics and Critical Phenomenon in a Bottom Blowing Bath". Advanced Materials Research 402 (novembre 2011): 365–70. http://dx.doi.org/10.4028/www.scientific.net/amr.402.365.

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Water model experiments were carried out to understand the behavior of the bubble formation near the immersion nozzle, bubble rising velocity in the liquid. The critical state appeared when Fr number changed from 5 to 6 was described. The character of the critical phenomenon was whether the evident separation between two continuous bubbles or air masses appeared.

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43

NAKAJIMA, Keiji, e Morio KAWASAKI. "Promotion of Inclusion Float-out in Continuous Casting Tundish Bath by Gas Blowing". Tetsu-to-Hagane 73, n. 7 (1987): 860–67. http://dx.doi.org/10.2355/tetsutohagane1955.73.7_860.

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44

Zhuang, Xupin, Kaifei Jia, Bowen Cheng, Xi Feng, Shaojun Shi e Bo Zhang. "Solution blowing of continuous carbon nanofiber yarn and its electrochemical performance for supercapacitors". Chemical Engineering Journal 237 (febbraio 2014): 308–11. http://dx.doi.org/10.1016/j.cej.2013.10.038.

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45

van der Knoop, W., W. H. L. Moonen, J. Post e G. van Unen. "Nitrogen control in liquid steel for slab casting". Revue de Métallurgie 92, n. 4 (aprile 1995): 503–10. http://dx.doi.org/10.1051/metal/199592040503.

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For the production of a two piece can (DWI), a continuous aonealed material for tin plate is preferred witb a low nitrogen content. At Hoogovens BOS No. 2, a steelmaking practice has been developed for the entire route to obtain N < 20 ppm. Major features are the blowing techniques to obtain low nitrogen in the BOF, prevention of -pick up during ladle treatrnent and improved shrouding at the caster.

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46

Xie, Zhipeng, Zeyong Hu, Lianglei Gu, Genhou Sun, Yizhen Du e Xiaoqiang Yan. "Meteorological Forcing Datasets for Blowing Snow Modeling on the Tibetan Plateau: Evaluation and Intercomparison". Journal of Hydrometeorology 18, n. 10 (1 ottobre 2017): 2761–80. http://dx.doi.org/10.1175/jhm-d-17-0075.1.

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Abstract In this paper, the reliability of the wind speed, temperature, humidity, pressure, and precipitation values of three surface meteorological forcing products [China Meteorological Administration Land Data Assimilation System, version 2 (CLDAS-2); China Meteorological Forcing Dataset (CMFD); and Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2)] in the Tibetan Plateau (TP) region was investigated from 2008 to 2014. Compared with the China Meteorological Administration (CMA) observations, CLDAS-2 exhibited the highest correlation coefficient for wind speed, CMFD displayed the best coefficients for temperature and specific humidity, and MERRA-2 best reflected pressure variations. Based on the biases, CLDAS-2 exhibited the best overall performance for temperature, specific humidity, and pressure, while CMFD displayed the best performance for wind speed. The high overall accuracy and false alarm ratio of precipitation based on MERRA-2 both stem from its continuous overestimation of the precipitation frequency. Both CLDAS-2 and CMFD overestimated the nonprecipitation frequency in comparisons with CMA observations, and a significant positive bias exists in MERRA-2 based on the analysis of daily precipitation. The results obtained from the comparisons with field observations over the TP and CMA observations are similar, except for the temperature and humidity biases of CLDAS-2. The meteorological effects on the coupled land–blowing snow modeling discussed in this paper suggest that the occurrence of blowing snow and snowdrift sublimation are projected to be reduced by CLDAS-2 due to the underestimation of wind speed, continual lack of snowfall events, and the positive biases in low temperatures and humidity, while simulations of blowing processes by MERRA-2 are likely to be much more severe than they actually are. These results may contribute to identifying deficiencies associated with the development of land surface models coupled with a blowing snow model.

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Wu, C. H., Y. Li, Y.-D. Liu, X. Xie, G. R. Wu e M. Zhang. "Numerical simulation and application of argon blowing from tundish cover for bloom continuous casting". Journal of Mining and Metallurgy, Section B: Metallurgy, n. 00 (2023): 27. http://dx.doi.org/10.2298/jmmb221027027w.

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Abstract (sommario):

During the continuous casting process, the remaining oxygen in the tundish can be significantly decreased by argon blowing from the tundish cover(ABTC). As a result, the effect of protective casting can be obviously improved, which helps decrease the reoxidation of molten steel in tundish. In the present work, numerical models for ABTC of a six-strand continuous casting machine were established and verified by the measured oxygen mass fraction in tundish during ABTC. The results indicate that the best conditions of ABTC are installing the argon pipes on either side of the tundish cover holes, sealing the baking holes, and keeping stopper rod holes open. The argon flow rate should be ?120m3/h during the period of empty tundish and ?60m3/h during the period of normal casting. Industrial trials of ABTC based on the calculation results were carried out. The results indicated that the increased nitrogen in steel(?w[N]) from the end of RH to tundish decreased by 21.5% from 8.78?10-6 to 6.89?10-6, and the amount of inclusions except for MnS in bloom (scanned size: 8mm?8mm) decreased by 21.3% from 13.43 to 10.57, and the average size of inclusions decreased by 19.0% from 9.27?m to 7.51?m.

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48

Edwige, Stéphie, Philippe Gilotte e Iraj Mortazavi. "Computational Analysis of Actuation Techniques Impact on the Flow Control around the Ahmed Body". Fluids 7, n. 2 (24 gennaio 2022): 52. http://dx.doi.org/10.3390/fluids7020052.

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Abstract (sommario):

Active flow control with jet devices is a promising approach for vehicle aerodynamics control. In this work an extended computational study is performed comparing three different actuation strategies for active flow control around the square back Ahmed body at Reynolds number 500,000 (based on the vehicle height). Numerical simulations are run using a Large Eddy Simulation (LES) approach, well adapted to calculate the unsteady high Reynolds number flow control using periodic jet devices. computations are validated comparing to in-house experiments for uncontrolled and some controlled cases. The novelty of this investigation is mainly related to the in-depth study of the base flow and actuation approaches by an accurate LES method and their comparison to experiments. Here, several simulations are performed to estimate the effect of active controls on the flow topology and the drag reduction. Beside the continuous blowing jet, three periodic actuation techniques including periodic blowing and suction as well as the zero flux synthetic jet devices are explored. The slots are implemented discontinuously in order to achieve a better control efficiency linked to vortex generation. In this framework, spectral analyses on global aerodynamical quantities, rear pressure/drag coefficient behavior examination as well as wake structure investigations are performed in order to compare these jet actuations. As a result, shear layer variations are observed during the blowing phase, but the main flow topology change occurs with suction and synthetic jets. Rear back pressure is therefore substantially increased.

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Опрышко, Б. А., В. А. Швецов, А. Э. Шагинян e О. А. Белавина. "Improved design of the head of a blowing production well". Vodosnabzhenie i sanitarnaia tehnika, n. 4 (15 aprile 2021): 11–14. http://dx.doi.org/10.35776/vst.2021.04.02.

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Abstract (sommario):

Камчатский государственный технический университет 683003, Россия, г. Петропавловск-Камчатский, Ключевская ул., 35, тел.: +7 (4152) 30-08-77, e-mail: oni@kamchatgtu.ru Предложена усовершенствованная конструкция оголовка для эксплуатационной самоизливающейся скважины водозаборов питьевых подземных вод. Оголовок относится к области технических средств, предназначенных для непрерывного контроля режима работы и гидрогеологического мониторинга водозаборов. Оголовок используется на скважинах, расположенных на неохраняемых территориях. Установка оголовка позволяет автоматизировать контроль работы скважин и мониторинг подземных питьевых вод, при этом повышается точность измерений контрольных параметров подземных вод. An improved design of the head for a blowing production well for drinking underground water intakes is proposed. A well head is assigned to the technical means for continuous monitoring of the operating mode and hydrogeological monitoring of water intakes. The head is used in wells located in unguarded areas. The installation of the head provides for the automated control of wells and monitoring of underground drinking water, while increasing the accuracy of measurements of the control parameters of underground waters.

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Yang, Xing Di. "Study on Refining Technology for Reducing the Content of T[O] in Steel". Advanced Materials Research 418-420 (dicembre 2011): 419–23. http://dx.doi.org/10.4028/www.scientific.net/amr.418-420.419.

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Abstract (sommario):

In order to produce low oxygen steel with high quality, converter slag-tapping, slag oxidability and oxygen activity have been analyzed. In addition, modifying and adding process of slag, control of slag oxidability and bottom argon-blowing in ladle were studied as well. On this basis, refining process which is beneficial to low oxygen steel producing with converter-continuous casting process has been developed. The results show that content of T[O] in steel is not more than 15×10-6.

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