Pieces Of Blade Research Articles

Modeling Design of Picohydro Power Generation System Using Crossflow Turbine

The goal of this project is to learn how to use a Crossflow turbine to create a Picohydro power plant system modeling. The manufacturing process, from design to evaluation, is the methodology employed. The turbine type utilized is a crossflow turbine, measuring 26 cm in outer diameter, 17.3 cm in inner diameter of the blade runner, and up to 35 pieces of blades. The calculations show that the distance between the blades is 2.3 cm, the blade length is 8.5 cm, the blade width is 4.4 cm, and the radius of curvature of the blade is 2.8 cm. The test results without load obtained the highest turbine rotation of 421 Rpm produces a voltage of 7.29 V before going through the boost converter.

Pengaruh Pengaruh Sudut Kemiringan Head Turbin Ulir Terhadap Daya Putar Turbin Ulir Dan Daya Output Pada Pembangkit Listrik Tenaga Mikro Hidro

The dependence of power plants on energy sources such as diesel, natural gas and coal is almost 75%, encouraging the development of renewable energy in an effort to meet the electricity supply. One of them is the micro hydro power plant by utilizing the potential of existing water. The working principle of PLTMH is to change the potential energy of water into electrical energy. In this final project has been designed modeling of micro hydro power plant by using screw turbine (Archimedes Screw). The turbine used resembles a drill bit, with a diameter of a turbine of 26 cm, a screw width of 10 cm, and an amount of 10 pieces of blade. Measurements made on the modeling of micro hydro power plants include: water discharge, turbine rotation, generator rotation, voltage, current, torque and generator output power and efficiency. The parameters are measured by changing the water fall on the turbine from the position of the turbine head angle 00, 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 700, 800 and 900 . The result of measurement that has been done on the parameters of micro hydro power plant modeling, obtained the highest measurement result at the corner of turbine head 400. The output power generated is 10.92 watts, torque is 0.60 Nm and efficiency of 14%. The results obtained are still low because the turbine rotation is less able to rotate the generator, where the generator torque is greater than the torque in the turbine. This is influenced by the small water discharges in the modeling of this micro hydro power plant.

PENGARUH VARIASI JUMLAH SUDU PADA SISTEM PEMBANGKIT LISTRIK TENAGA AIR TERHADAP DAYA YANG DIHASILKAN

Indonesia has the potential of water that can become electricity with a hydroelectric power plant. In addition, the distribution of the PLN network has not reached all regions of Indonesia. From these problems the author made a hydropower generator by comparing the number of blades used with a number of 8, 10, and 12 pieces. This study aims to determine the power that will be generated from the number of blades. Data retrieval is done by calculating the power produced by the turbine with a variation of the test time of 20 minutes by 5x. The working principle of this tool is that the water will rotate the wheel connected to the generator with the help of shafts, bearings, pulleys, and V-belts that produce electrical power in the battery so that the electricity can be directly used. The results obtained that the output power is the largest in the use of a number of 12 pieces of blades namely 0.0687 HP, while the number of blades 8 and 10 pieces produces the amount of output power of 0.0627 HP and 0.0652 HP.

Ice detection using thermal infrared radiometry on wind turbine blades

Abstract Wind farms are located in areas with a high probability of ice occurrence. Icing involves problems such as energy losses, mechanical failures and downtimes. The priority is to detect icing in order to avoid these problems. Icing detection is a complex procedure for example, low temperatures are not a guaranty of ice formation, and other variables may affect. Different techniques have been recently proposed to detect ice in wind turbine blades. They are mainly based on damping of ultrasonic waves on the blade surface, or measuring the resonant frequency of a probe. But these methods have some drawbacks that may cause the system to fail, e.g. the behaviour of ultrasonic waves in composite materials is difficult to predict due to different fibre orientations, and the ice detection by changes in the resonance frequency could lead to false alarms due to variations in working conditions. This paper takes advantage of the remote sensing techniques to propose a novel approach for icing detection without physical contact. The approach is based on the drastic emissivity change that it is produced over a surface characterized with a low emissivity value when ice appears. An experiment was conducted using a broad-band thermal radiometer and a section of a wind turbine blade. Radiometric temperature measurements were collected over the blade with and without an aluminium foil patch. The piece of blade was cooled down and different scenarios were considered, including frozen with and without ice. This study was completed with a sensitivity analysis of the approach to dust accumulation, accounting for real operation conditions. Results show the feasibility of this technique to detect ice formation and discern between frozen and icing conditions.

Analysis of throw distances of detached objects from horizontal-axis wind turbines

This paper aims at predicting trajectories of the detached fragments from wind turbines, in order to better quantify consequences of wind turbine failures. The trajectories of thrown objects are attained using the solution to equations of motion and rotation, with the external loads and moments obtained using blade element approach. We have extended an earlier work by taking into account dynamic stall and wind variations due to shear, and investigated different scenarios of throw including throw of the entire or a part of blade, as well as throw of accumulated ice on the blade. Trajectories are simulated for modern wind turbines ranging in size from 2 to 20 MW using upscaling laws. Extensive parametric analyses are performed against initial release angle, tip speed ratio, detachment geometry, and blade pitch setting. It is found that, while at tip speeds of about 70 m/s (normal operating conditions), pieces of blade (with weights in the range of approximately 7-16 ton) would be thrown out less than 700 m for the entire range of wind turbines, and turbines operating at the extreme tip speed of 150 m/s may be subject to blade throw of up to 2 km from the turbine. For the ice throw cases, maximum distances of approximately 100 and 600 m are obtained for standstill and normal operating conditions of the wind turbine, respectively, with the ice pieces weighting from 0.4 to 6.5 kg. The simulations can be useful for revision of wind turbine setback standards, especially when combined with risk assessment studies. Copyright © 2015 John Wiley & Sons, Ltd.

Escalating Ingestion of Razor Blades in a Patient With Borderline Personality Disorder.

To the Editor: The means employed in self-injury vary widely among patients with borderline personality disorder and so may the magnitude of the damage inflicted. Deliberate foreign body ingestion (DFBI) constitutes a distinct behavioral syndrome that is frequently associated with borderline personality disorder. While with other forms of self-injurious behavior the patient usually achieves an immediate release of tension, such release is not generally the case in DFBI, as is illustrated in the present case. Case report. A 23-year-old woman who had previously been diagnosed with borderline personality disorder, according to ICD-10 criteria, presented with an increase in self-injurious behaviors after a recent miscarriage. The patient herself contacted police regarding increasing suicidal tendencies, which led to her admission to a psychiatric ward. Physical examination at admission revealed old scars and superficial cuts on arms and legs as well as new deep cuts all over her torso. The patient received individual psychotherapy sessions as well as group skills training. During her stay, she repeatedly swallowed quartered pieces of broken razor blades, which she wrapped in wads of chewing gum. During the span of several weeks, she swallowed in excess of 30 such razor blade pieces essentially without complications. She always notified staff sometime after the act. Ingestion of razor blade pieces was confirmed by x-ray (Figure 1A). For the most part, these fragments were passed with no difficulty. However, several larger pieces were recovered endoscopically either for diagnostic purposes or because the patient had complained of pain in her abdomen. Figure 1. Repeated Ingestion of Broken Razor Blades in a Patient With Borderline Personality Disorder In all, the patient underwent 4 gastroscopy or colonoscopy sessions (Figure 1B and 1C). Luckily for the patient, no transmural lesions had occurred. At this point, it was deemed impossible to discharge the patient from the hospital because she was considered at acute risk of suicide. Subsequently, she attempted to swallow one-half of a 2-edged razor blade without chewing gum, which resulted in immediate esophageal perforation and, consequently, in mediastinal emphysema and an esophagotracheal fistula. The patient required intensive care and several courses of endoscopic sponge therapy to close the esophageal defect. During this time, she was regularly seen by liaison psychiatry. She gradually began to engage more actively in psychotherapeutic treatment. In parallel, self-injurious behaviors decreased, and the patient was eventually discharged. An elective readmission for dialectical behavior therapy was scheduled. Deliberate foreign body ingestion is a frequent occurrence in patients with borderline personality disorder, but may also occur in patients with psychosis, malingering, and pica. The latter condition is defined as the persistent ingestion of nonnutritive materials such as chalk or clay at an age at which this behavior is developmentally inappropriate. The course of DFBI is frequently chronic. Treatment is difficult. Evidence-based therapeutic interventions are largely lacking.1 In borderline personality disorder, most self-injurious behaviors are a means of affect regulation and frequently lead to a swift release of tensions. In general, this release does not appear to be the reason behind DFBI.1 The main drivers behind DFBI in borderline personality disorder seem to be an inappropriate need for attention as well as a desire to test the limits of the therapeutic relationship. Management of DFBI in borderline personality disorder poses a great challenge because of potentially lethal complications and the need for rapid medical attention. Here, it is the special role of the consultant-liaison psychiatrist to bridge the gap between medical and physical health care and to support medical and surgical colleagues in grappling with countertransference issues commonly involved in treating such patients. In our experience, it is frequently during the early period after a major complication has occurred that the patient becomes more open to psychotherapeutic interventions. Ideally, general psychiatric management and stabilization will gradually enable the patient to benefit from a specific psychotherapeutic intervention such as dialectical behavior therapy.1,2

Estimation of useful life in turbines blades with cracks in corrosive environment

Geothermal turbines of 110MW were installed in the Federal Electricity Commission in Cerro Prieto Mexico, which operating time exceeds 150,000h. Therefore, the critical components which determine the useful life of the turbine should be evaluated to determine the rehabilitation or replacement of them. The critical components are the blades of the last stage in the steam turbine. It has been observed that different blades of the turbine of 110MW with cracks presented corrosion products, which resulted in a failure for corrosion fatigue mechanisms. In this paper, it was studied the effect of crack propagation produced in a geothermal turbine blade of the last stage, L-0, which is made of stainless steel AISI 410 exposed to corrosion under a sea water solution. The corrosion phenomena including localized corrosion suffered by the cracking sample were studied through the electrochemical noise technique in current and potential and polarization curves. The tests were conducted on pieces of blades subjected to fatigue. The results indicated that the exposure to the corrosion solution modified the width and the length of the cracks. Using a scanning electron microscopy (SEM), the surface of the crack was observed, showing that the corrosion mechanism produced a significant increment of the velocity of crack propagation and therefore, a decrement of the useful life of the material. This research will allow us to understand the corrosion process in addition to estimate the useful life of the blades when they are subjected to load cycles.

CHIMERAS WITH MOSAIC PATTERN IN ARCHEOSPORE GERMLINGS OF PYROPIA YEZOENSIS UEDA (BANGIALES, RHODOPHYTA)(1).

In the marine crop Pyropia yezoensis (Ueda) M. S. Hwang et H. G. Choi, it is known that conchospores from heterozygous conchocelis develop into sectored gametophytic blades (chimeras), but archeospores asexually released from haploid blades do not usually grow into chimeric blades. In this study, chimeras with mosaic pattern consisting of the green and wildtype colors were developed from archeospores that were released from a blade piece containing a cell cluster of green color induced by heavy-ion beam irradiation. To make clear whether these archeospores were produced from the green-colored cells or the wildtype-colored cells, cell clusters of the green mutant, wildtype, and mosaic pattern were cut out from the grown chimera, and archeospores were released from each of the three blade pieces. Archeospores from the green-mutant blade piece and from the wildtype blade piece developed into only green-mutant blades and wildtype blades, respectively. In contrast, archeospores from the blade piece with mosaic pattern developed into green-mutant blades, wildtype blades, and chimeric blades with mosaic pattern of the two colors, although the frequency of the chimeras was low. Because each gametophytic cell possesses a single plastid, it is difficult to explain the occurrence of the new chimeras as a mutation of the plastid DNA. Thus, the new chimeras are considered to be due to transposable elements in Pyropia.

The experimental study of sympathetic ophthalmia in rat induced by intraocular foreign body injury model

Objective To investigate whether sympathetic ophthalmia could be induced by setting up the rat model of unilateral mechanical ocular trauma.And to discuss the mechanism of sympathetic ophthalmia.Methods 36 Wistar rats were randomly divided into three groups.In group Ⅰ,one piece of stone embeded in one eye (n =16) ; group Ⅱ,with a piece of blade embeded in one eye (n =16) ; groupⅢ,normal eye as control group (n =4).In group Ⅰ and group Ⅱ,intraocular foreign bodies were embeded from pars plana into the vitreous of the right eyes.All the eyes were observed with the loupe.The histopathological changes were observed under HE stain and microscopy 2 weeks,4 weeks,6 weeks and 8 weeks after the establishment of injury model.Results In group Ⅰ and group Ⅱ,abnormal secretions,the conjunctiva congest and oedema were main manifest in the right eyes.The number of atrophy of eyeballs increased with the time past.Histopathology showed lymphocytes and neutrophilic granulocytes infiltration in the eyeball.And abnormal changes were not found in group Ⅲ.It was failed to evocate the sympathetic ophthalmia in the injury models.Conclusion The pathogenesis of sympathetic ophthalmia is complex.Sympathetic ophthalmia were not evocated by setting up rat models of mechanical eye injury. Key words: Sympathetic ophthalmia; Intraocular foreign body; Histopathology

La frontière entre le Châtelperronien et l’Uluzzien : analyse comparative des typologies lithiques sur la base des dernières découvertes

The end of the Middle Paleolithic sees the appearance of “transitional” industries, which emerge at the same moment as anatomical modern humans enter Europe. All these transitional industries come from a Mousterian background and are closely connected to late Neanderthals. Among these industries we find two traditions characterized by backed blade pieces in Western Europe: the Châtelperronian and the Uluzzian. Two big conditions have been defined to allow a comparison between these industries: a chronological continuity and a geographic link. The recent data allows a new comparison.

Intra-plant differences in seaweed nutritional quality and chemical defenses: Importance for the feeding behavior of the intertidal amphipod Orchestoidea tuberculata

As a result of their morphological complexity, large macroalgae show intra-thallus variations in their nutritional composition and secondary metabolite content, which influences the trophic ecology of herbivorous invertebrates, and ultimately their fitness. In this study, we evaluated for the first time the variability in nutritional quality (protein content, carbohydrates, lipids, and total organic matter), secondary metabolites (phlorotannins), and structure (shape and toughness) between blades and stipes of the macroalgae Durvillaea Antarctica. Specifically, we looked at their effect on feeding preference, rate of consumption, absorption efficiency, and growth rate of the amphipod Orchestoidea tuberculata, one of the most abundant organisms on Chilean sandy beaches. Proteins, carbohydrates, total organic matter and phlorotannin contents were significantly higher in blades than in stipes. Preference experiments revealed that the amphipods preferred blades when fresh pieces of blades and stipes were offered at the same time. Similar results were found when artificial food (in which structures of both parts of the alga were standardized) was offered, suggesting that shape and toughness of the two different parts of the alga did not influence preference patterns of O. tuberculata. Absorption efficiency of O. tuberculata was higher on blades compared to stipes. When the amphipods were kept with each of the algal parts separately (i.e. no choice), they consumed a significantly higher amount of stipe, which suggests that O. tuberculata used food quantity to compensate for the lower nutritional quality of stipes. The higher nutritional values of blades compared to stipes appears to explain observed preference patterns by O. tuberculata. Phlorotannin content did not appear to inhibit blade consumption, suggesting that the nutritional quality of the food could be more important than chemical defense in determining food choice in O. tuberculata. Growth did not differ between the amphipods maintained with either blades or stipes (i.e. no choice), which is consistent with the hypothesis of compensatory feeding. To conclude, O. tuberculata can actively select specific parts of an alga and this selection appears to be based on nutritional quality. The capacity for using different feeding strategies allow O. tuberculata, in some cases, to successfully exploit food types with different nutritional qualities.

Climbing performance of sea urchinStrongylocentrotus nudusfor upright, thin objects in wave-induced oscillatory flow

In order to examine the possibility of creating kelp beds with upright thin structures above sea urchin-dominated barrens, oscillating-flow-tank experiments were conducted on the climbing performance by the sea urchin Strongylocentrotus nudus using upright rods of two different diameters (3 and 10 mm) with five blade pieces of the kelp Eisenia bicyclis as algal food attached at 2.5-cm intervals in four levels of orbital velocities (0, 0.2, 0.3 and 0.4 m/s). In the absence of oscillatory flow urchins readily climbed to graze on food items in sequence from the bottom. The frequency of grazing up to the top food significantly decreased with velocity but no significant difference in the frequency was detected between the thin and thick rods. Fitting of a Markovian model with stationary transition probability to the observed frequency of the grazed height (number of pieces of food eaten from the bottom) suggested that, once climbing was initiated, an urchin continued to climb at a particular rate determined by the water motion. The resultant model predicted that, even with increasing height of upright rods, an orbital velocity higher than at least 0.1 m/s would be required to prevent urchin invasion in urchin-dominated barrens.

A case of reverse engineering for the manufacture of wide chord fan blades (WCFB) used in Rolls Royce aero engines

The paper describes the manufacturing process for wide chord fan blades (WCFB) and how the production of die sets used for their manufacture can be substantially improved using reverse engineering. Super plastic formed WCFBs are manufactured by diffusion bonding five separate blade pieces under high pressure. The blade is then hot creep formed into the required shape, using pressure to force the blade against the die walls to yield the desired form, blade twist and the honeycomb centre required. Two die sets are required, one for the hot creep forming of the blade billet and the second for the super plastic blade forming process. Their manufacture requires three solid models to be generated from a bespoke ‘Fan Key System’. This calculates the die set geometry required for both hot and cold states. The three solid models comprise the casting model geometry which incorporates the draw angle and shrinkage allowance, the pattern model for the top and bottom die sets and a die set model used to define the NC part programs for the five axis finish machining process. The machining process has three elements, pre-machining sometimes termed water line or terrace machining, semi-finish and finish machining. Distortion caused by rate of cooling, graphite precipitation and mould dilation cause massive amounts of metal removal in the waterline machining process which can take up to 35 h and is a non-value added process. It often leaves the die wall thin with the resulting effect on performance and life. A reverse engineering solution was used to improve the geometry of the castings by predicting die distortion more accurately. Point cloud models of nine casting sets were imported into reverse engineering software, ‘Surfacer’ which made possible a comparison with the surface geometry representation required. The resulting design information enabled more accurate die set design. Waterline machining had been substantially reduced and die life has been extended.

Selection of hairy root clones of Artemisia annua L. for artemisinin production

Hairy roots were induced from two kinds of explants and selection of hairy root clones was studied for artemisin in production. Leaf blade pieces and petiole segments of Artemisia annua plantlets were infected with Agrobacterium rhizogenesstrain 1601. The efficiency of leaf blade pieces forming hairy roots was higher than that of petiole segments. Light promoted hairy root induction and branching. Two hundred and twenty hairy root clones showed considerable variations in capacity of growth and branching. Six hairy root clones were established in suspension culture and showed obvious differences in their biomass and artemisin in content. Among six clones, clone 1601-L-3 produced the highest biomass, more than 70 times the inoculum, while clone 1601-L-1 gave the lowest biomass. The artemisin in content of clone 1601-L-1 was the highest, 1.195 mg/g DW, and this line yielded the highest artemisinin level of 9.08 mg/L.

Chloroplast changes and differentiation of callus cells in Eckloniopsis radicosa (Kjellman) Okamura (Phaeophyta, Laminariales)

Excised rectangular blade pieces of young sporophytes of Eckloniopsis radicosa (Kjellman) Okamura were cultured at four different temperatures (10, 15, 20, 25 °C) and light intensities (10, 20, 40, 80 µmol photon m−2 s−1) to observe callus cell propagation and differentiation. Although rapidly propagating callus cells were observed at a low temperature (15 °C) and low light intensities of (10–20 µmol photon m−2 s−1), differentiation to bladelets was only observed at higher temperatures and light intensities. In rapidly propagating callus cells, the chloroplasts decreased in both size and number. When callus cells with few chloroplasts were exposed to high temperature and light intensity, the chloroplasts gradually increased in number and size until they were the same size as found in cells from young blades. Finally, these cells differentiated and produced bladelets. This is the first report describing a relationship between differentiation and chloroplast size and number in the callus cells on E. radicosa.

Swallowed Foreign Bodies in Children: Aspects of Management

Swallowed Foreign Bodies in Children: Aspects of Management

Studies of Damascus steel blades: Part II—Destruction and reformation of the patterns

Two genuine Damascus steel blades and two reconstructed Damascus blades have been austenitized to the point where all of the cementite particles responsible for their Damask pattern were dissolved into the austenite. It is demonstrated that subsequent thermal cycling causes the reprecipitation of cementite particles in the same sheetlike morphology of the original blades, provided that the austenization temperature is low enough to avoid homogenization of the major impurity elements. Mn, Si, S, and P. The results provide strong support for the hypothesis of Part I[ Materials Characterization 30:175–186 (1993)], that the formation of sheets of clustered cementite particles in geniune Damascus blades is a type of carbide banding caused by microsegregated third elements deformed into sheets during the cyclic process. Several thermal cycling experiments on reconstructed blade pieces are presented. The experiments support a model in which the third-element additions bias the nucleation of cementite particles into the sheet geometry, followed by enhancement of the sheet morphology by particle coarsening during the thermal cycles.

SOMATIC EMBRYOGENESIS AND PLANTLET REGENERATION FROM SHOOT EXPLANTS OF Hamelia patens

A variety of Hamelia patens (firebush) explants (nodal and internodal segments, leaf blade pieces, floral buds, shoot tips) were cultured on Murashige and Skoog's revised medium containing various concentrations of 2,4-D and kinetin. Embryogenic callus was produced only from shoot-tip explants placed on media containing 2,4-D or 2,4-D plus kinetin. None of the other explants produced embryogenic callus. Somatic embryogenesis from callus was greatest on media containing both 2, 4-D and kinetin. Direct somatic embryogenesis was observed on the roots of callus-derived primary embryos maintained on media containing 2,4-D or 2,4-D plus kinetin. Conversion of somatic embryos into plantlets only occurred on media containing 2,4-D, kinetin and activated charcoal.

The Sharpness of Incision Instruments in Corneal Tissue

ABSTRACT Because breadths of surgical blades are very difficult to measure directly, we designed a method to measure sharpness of a variety of instruments by determining the power they required to incise corneal tissue to a uniform depth. Diamond knives were the sharpest, followed by razor blade pieces individually prepared by a special new method. Ruby knives varied considerably. The method of measuring sharpness described may allow manufacturers to improve and stabilize production methods, as well as enable surgeons with such knowledge in advance of surgery to optimize wound healing and maximize cost-effectiveness.