ANALYSIS OF BLADE DESIGN HORIZONTAL AXIS WIND TURBINE

The demand for power is increasing day by day in India. We depend upon the traditional fuel for power production. We know that our traditional fuel resources are limited which is getting short day by day. In this condition wind power can be a very suitable replacement for power production. Particularly in rural India the domestic turbine or micro wind turbine can play an important role as it is cheaper than the other sources of power production. Computers are used to perform the calculations required to simulate the interaction of liquids and gases with surfaces defined by boundary condition. In this paper, CFD analysis of wind turbine blade, a complete drawing, and details of sub-system are carried out. Angle of twisted also has a great impact on power output if the angle of twist range is kept within the optimized limit of change of angle of attack the turbine would be more sensitive to change in wind speed

Efficacy and Safety of Intravitreal Triamcinolone Acetonide in the Management of Recalcitrant Diabetic Macular Edema

PURPOSE: To evaluate the safety and efficacy of intravitreal triamcinolone acetonide in the management of recalcitrant diabetic macular edema unresponsive to laser photocoagulation and the intravitreal anti-VEGF agent, bevacizumab. DESIGN: Prospective, non-comparative, interventional study. PARTICIPANTS: Twenty-one eyes of seventeen patients with clinically significant macular edema(CSME) that failed to respond to laser photocoagulation and 2 doses of intravitreal anti-VEGF agent, bevacizumab in which resolution of macular edema had not occurred within one month of treatment, as assessed by clinical examination and measured by optical coherence tomography (OCT) and are recalcitrant. METHODS: Eyes were diagnosed with recalcitrant diabetic macular edema which exhibited best corrected visual acuity (BCVA) of 6/18 or worse, with central macular thickness of more than 300 μm (normal 200 μm) were treated with 2 mg of intravitreal triamcinolone acetonide; and followed up for a period of 6months at intervals of 1 week, 1 month, 3 months and 6 months following the intravitreal injection. The visual and anatomic responses were observed as well as complications related to the injection procedure and corticosteroid medication. MAIN OUTCOME MEASURES: The response to treatment was monitored functionally by best corrected visual acuity and anatomically by OCT by measuring central macular thickness quantitatively. Potential complications were monitored functionally by looking for decrease in visual acuity of one line by Snellen’s chart, rise in intraocular pressure greater than 3omm of Hg not responding to anti-glaucoma medications, progression of cataract, retinal detachment, vitreous hemorrhage, and endophthalmitis. RESULTS: All patients completed 6 months follow-up period. The mean best corrected visual acuity (BCVA) in the eyes that received triamcinolone acetonide (TA) was (in decimals) 0.14 ± 0.07 (pre injection), 0.26 ± 0.12 (one week after injection of TA), 0.39 ± 0.20 (one month after injection of TA), 0.32 ± 0.15 (3 months after injection of TA) and 0.18 ± 0.10 (6months after injection of TA; these differences were statistically significant (one-way analysis of variance [ANOVA]; Fisher ‘f’ value = 11.804; P < 0.001). The mean central foveal thickness (CFT) in eyes with recalcitrant diabetic macular edema that received triamcinolone acetonide was (in μm) 536.5 ± 115.3 (pre injection), 380.7 ± 95.6 (1 week post injection), 280.9 ± 71.6 ( one month post-injection), 283.6 ± 76.8 (three months post-injection) and 370.2 ± 114.3 (six months post-injection); these differences were statistically significant [one-way ANOVA; Fisher ‘f’ value = 24.4; P < 0.001]. The mean HbA1C value was 8.2% at baseline,7.7% at 3 months and 7.7% at 6 months follow-up; this reduction in mean HbA1C values was not statistically significant.( P=0.06 ). The mean intraocular pressure (IOP) in the eyes with recalcitrant diabetic macular edema that received triamcinolone acetonide was (in mm Hg) 17.4 ± 2.2 (pre injection), 18.0 ± 2.1 (1 week post injection), 18.4 ± 2.2 ( one month post-injection), 18.6 ± 5.12 (three months post-injection) and 20.3 ± 11.8 (six months post-injection); these differences were not statistically significant (ANOVA; Fisher ‘f’ value = 0.689; P = 0.6). Of the 18 phakic eyes, four eyes ( 22.2%) developed cataract following intravitreal injection of triamcinolone acetonide for which cataract surgery and intraocular lens implantation were done. Severe complications, such as infectious endophthalmitis or retinal detachment, were not observed within the follow-up period in the present study. CONCLUSION: Intravitreal triamcinolone acetonide appears to be effective in the management of recalcitrant diabetic macular edema and improvement in best corrected visual acuity was statistically significant in the short term (1 month and 3 months). The effect of intravitreal triamcinolone acetonide appears to be transient, necessitating repeat injections 6 months after the first dose. Intravitreal triamcinolone acetonide can still be a safe therapeutic option in patients who are resistant to conventional laser photo coagulation and intravitreal anti-VEGF agents. Further study is warranted to assess the long-term efficacy and safety of triamcinolone acetonide and the need for retreatment

Numerical Investigation into the Effect of Splats and Pores on the Thermal Fracture of Air Plasma-Sprayed Thermal Barrier Coatings

The effect of splat interfaces on the fracture behavior of air plasma-sprayed thermal barrier coatings (APS-TBC) is analyzed using finite element modeling involving cohesive elements. A multiscale approach is adopted in which the explicitly resolved top coat microstructural features are embedded in a larger domain. Within the computational cell, splat interfaces are modeled as being located on a sinusoidal interface in combination with a random distribution of pores. Parametric studies are conducted for different splat interface waviness, spacing, pore volume fraction and fracture properties of the splat interface. The results are quantified in terms of crack nucleation temperature and total microcrack length. It is found that the amount of cracking in TBCs actually decreases with increased porosity up to a critical volume fraction. In contrast, the presence of splats is always detrimental to the TBC performance. This detrimental effect is reduced for the splat interfaces with high waviness and spacing compared to those with low waviness and spacing. The crack initiation temperature was found to be linearly dependent on the normal fracture properties of the splat interface. Insights derived from the numerical results aid in engineering the microstructure of practical TBC systems for improved resistance against thermal fracture

Effect of process parameters on tire pyrolysis: a review

309-315This review presents pyrolysis of scrap tires with a focus on effect of process parameters (reactor temperature, gas flow rate and catalyst-tire ratio) on yield. Three commercially important pyrolysis by-products from scrap tires are carbon residue, pyrolitic oil and pyro-gas. Pyrolysis of scrap tire starts at 250°C and gets completed at 550°C. Presence of catalysts produces lighter oil with a drastic increase in the concentration of single ring aromatics

Fabrication and Characterization of CU/B4C Surface Dispersion Strengthened Composite using Friction Stir Processing

Friction stir processing has evolved as a novel method to fabricate surface metal matrix composites. The feasibility to make B4 C particulate reinforced copper surface matrix composite is detailed in this paper. The B4 C powders were compacted into a groove of width 0.5 mm and depth 5 mm on a 9.5 mm thick copper plate. A tool made of high carbon high chromium steel; oil hardened to 63 HRC, having cylindrical profile was used in this study. A single pass friction stir processing was carried out using a tool rotational speed of 1500 rpm, processing speed of 40 mm/min and axial force of 10 kN. A defect free interface between the matrix and the composite layer was achieved. The optical and scanning electron micrographs revealed a homogeneous distribution of B4 C particles which were well bonded with the matrix. The hardness of the friction stir processed zone increased by 26% higher to that of the matrix material.Zgrzewanie tarciowe ewoluowało jako nowa metoda wytwarzania kompozytów powierzchniowych z osnową metaliczną. W pracy szczegółowo opisano możliwość wytworzenia kompozytu na powierzchni miedzi zbrojonego cząstkami B4 C. Proszki B4 C sprasowano w rowku o szerokości 0,5 mm i głębokści 5 mm wykonanym na blasze miedzianej o grubości 9,5 mm. Do wytworzenia kompozytu użyto narzędzia o profilu cylindrycznym, z wysokowęglowej stali o wysokiej zawartości chromu, hartowanego w oleju do 63 HRC. W jednym przebiegu obróbki zgrzewanie przeprowadzono przy prędkości obrotowej narzędzia 1500 obr/min. szybkości przesuwu 40 mm/min i osiowej siły 10 kN. Osiągnięto cel w postaci pozbawionego wad połączenia pomiędzy matrycą i warstwą kompozytu. Mikrofotografie optyczne i ze skaningowej mikroskopii elektronowej wykazały jednorodną dystrybucję cząstek B-C, które były dobrze połączone z matrycą. Twardość strefy zgrzewnej tarciowo wzrosła o 26% w stosunku do materiału matrycy

Wytwarzanie metodą zgrzewania tarciowego i charakterystyka powierzchniowodyspersyjnie wzmacnianego kompozytu Cu/B₄ C

Friction stir processing has evolved as a novel method to fabricate surface metal matrix composites. The feasibility to make B4 C particulate reinforced copper surface matrix composite is detailed in this paper. The B4 C powders were compacted into a groove of width 0.5 mm and depth 5 mm on a 9.5 mm thick copper plate. A tool made of high carbon high chromium steel; oil hardened to 63 HRC, having cylindrical profile was used in this study. A single pass friction stir processing was carried out using a tool rotational speed of 1500 rpm, processing speed of 40 mm/min and axial force of 10 kN. A defect free interface between the matrix and the composite layer was achieved. The optical and scanning electron micrographs revealed a homogeneous distribution of B4 C particles which were well bonded with the matrix. The hardness of the friction stir processed zone increased by 26% higher to that of the matrix material.Zgrzewanie tarciowe ewoluowało jako nowa metoda wytwarzania kompozytów powierzchniowych z osnową metaliczną. W pracy szczegółowo opisano możliwość wytworzenia kompozytu na powierzchni miedzi zbrojonego cząstkami B4 C. Proszki B4 C sprasowano w rowku o szerokości 0,5 mm i głębokści 5 mm wykonanym na blasze miedzianej o grubości 9,5 mm. Do wytworzenia kompozytu użyto narzędzia o profilu cylindrycznym, z wysokowęglowej stali o wysokiej zawartości chromu, hartowanego w oleju do 63 HRC. W jednym przebiegu obróbki zgrzewanie przeprowadzono przy prędkości obrotowej narzędzia 1500 obr/min. szybkości przesuwu 40 mm/min i osiowej siły 10 kN. Osiągnięto cel w postaci pozbawionego wad połączenia pomiędzy matrycą i warstwą kompozytu. Mikrofotografie optyczne i ze skaningowej mikroskopii elektronowej wykazały jednorodną dystrybucję cząstek B-C, które były dobrze połączone z matrycą. Twardość strefy zgrzewnej tarciowo wzrosła o 26% w stosunku do materiału matrycy