Genetic characterization of native donkey (Equus asinus) populations of Turkey using microsatellite markers

This study presents the first insights to the genetic diversity and structure of the Turkish donkey populations. The primary objectives were to detect the main structural features of Turkish donkeys by microsatellite markers. A panel of 17 microsatellite markers was applied for genotyping 314 donkeys from 16 locations of Turkey. One hundred and forty‐two alleles were identified and the number of alleles per locus ranged from 4 to 12. The highest number of alleles was observed in AHT05 (12) and the lowest in ASB02 and HTG06 (4), while ASB17 was monomorphic. The mean HO in the Turkish donkey was estimated to be 0.677, while mean HE was 0.675. The polymorphic information content (PIC) was calculated for each locus and ranged from 0.36 (locus ASB02) to 0.98 (locus AHT05), which has the highest number of alleles per locus in the present study. The average PIC in our populations was 0.696. The average coefficient of gene differentiation (GST) over the 17 loci was 0.020 ± 0.037 (p < 0.01). The GST values for single loci ranged from −0.004 for LEX54 to 0.162 for COR082. Nei’s gene diversity index (Ht) for loci ranged from 0.445 (ASB02) to 0.890 (AHT05), with an average of 0.696. A Bayesian clustering method, the Structure software, was used for clustering algorithms of multi‐locus genotypes to identify the population structure and the pattern of admixture within the populations. When the number of ancestral populations varied from K = 1 to 20, the largest change in the log of the likelihood function (ΔK) was when K = 2. The results for K = 2 indicate a clear separation between Clade I (KIR, CAT, KAR, MAR, SAN) and Clade II (MAL, MER, TOK, KAS, KUT, KON, ISP, ANT, MUG, AYD and KAH) populations. © 2020 by the authors. Licensee MDPI, Basel, Switzerland

Hydrogen production potential and cost of wind-hydrogen hybrid energy system

ASME International Mechanical Engineering Congress and Exposition -- NOV 09-15, 2012 -- Houston, TXWOS: 000350070400183Main aim of this study is to investigate annual wind power output, annual hydrogen production quantity and hydrogen production cost of wind-hydrogen energy system in the Pinarba i-Kayseri region in Turkey which has remarkable wind potential in the central region of Turkey. Turkish State Meteorological Service (TSMS) measured the value of mean wind speed of Pmarba i. as 3.67 m/s above 10m ground between 2000 and 2006 years. In this study, three different hub heights (50m, 80m and 100m) were considered, and so the measured mean wind speed at 10m was extrapolated to considered heights and annual wind power output was calculated. Four different turbine rated powers (800kW, 900kW, 2000kW and 3000 kW) and two different electrolyser powers (120kW and 40kW) for hydrogen production were assumed. Levelised cost of electricity method was used in order to determine the cost analysis of wind energy and hydrogen production. The results of this study bring out clearly the variation of potential of hydrogen production and cost with wind speed, wind turbine hub height and wind turbine rated power and electrolyser power.ASM

Düşük Re Sayılı Akışda Naca2415 Kanat Profili Üzerindeki Ayrılma Kabarcığının Sayısal Ve Deneysel İncelenmesi

Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2010Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2010Düşük Re sayılı akışlarla; mini, mikro ve insansız hava araçlarının uçuşlarında, rüzgar türbini kanatları üzerindeki akışlarda, model uçaklarda, böcek, sinek gibi küçük uçan hayvanların uçuşlarında karşılaşılır. Bu tür hava araçlarında türbülansa geçiş akışları ve laminer akım ayrılması ile karşılaşıldığından akışın yapısı ve hava aracından elde edilebilecek en yüksek taşıma önem kazanmaktadır. Bu nedenle düşük Re sayılı akışların ve bu akışlarda meydana gelen ayrılma kabarcığının yapısı ve davranışı iyi bilinmelidir. Bu çalışmada, 2,xl 05 Re sayılı türbülansa geçiş akışında NACA2415 kanat profili etrafındaki akış sayısal ve deneysel olarak incelenmiştir. Deneysel çalışmalar, hem Batla Üniversitesi'nde hem de TOBB Ekonomi ve Teknoloji Üniversitesi'nde yapılmıştır. Sayısal benzeşimler ise, FLUENT FM yazılımında türbülans ve türbülansa geçiş benzeşim modelleri ile gerçekleştirilmiştir. NACA2415 profili üzerinde bu Re sayısında deneylerde lamineı• ayrılma kabarcığı oluşmuştur. Sayısal benzeşim için lam türbülanslı ve türbülansa geçiş modelleri denenmiş ve Ree2x105 iken akım fiziksel olarak bir geçiş akımı olduğu için türbülansa geçiş modelleri gerçeğe daha yakın sonuç vermiştir

AN EXPERIMENTAL STUDY OF PERPENDICULAR ACOUSTIC DISTURBANCES EFFECT ON FLOW OVER AN AEROFOIL AT LOW REYNOLDS NUMBERS

In this study, the effect of perpendicular acoustic excitation on laminar separation bubble over a NACA2415 aerofoil and stall characteristics of the aerofoil was investigated experimentally at low Reynolds numbers (50000 and 75000) and various angles of attack on the aerofoil using force measurement, pressure measurement and smoke-wire flow visualization techniques. The experiments of resonance characteristics of test section of the wind tunnel showed that the frequencies used for acoustic control were not equal to the peak (resonance) frequencies of the wind tunnel test section. The experimental results of acoustic control showed that when acoustic excitation of a certain frequency was applied, the length of the laminar separation bubble was shortened owing to the energy added to the flow by acoustic excitation. Because of the shortened laminar separation bubble, coefficient of lift was increased. Furthermore, at the stall angles the separated flow was forced to reattach to the surface of the aerofoil, so the stall angle was increased from 12 degrees to 17 degrees and maximum coefficient of lift was increased from 1.16 to 1.24 at Re=50000 and from 13 degrees to 18 degrees and maximum coefficient of lift was increased from 1.18 to 1.34 at Re=75000

AN EXPERIMENTAL STUDY OF PERPENDICULAR ACOUSTIC DISTURBANCES EFFECT ON FLOW OVER AN AEROFOIL AT LOW REYNOLDS NUMBERS

In this study, the effect of perpendicular acoustic excitation on laminar separation bubble over a NACA2415 aerofoil and stall characteristics of the aerofoil was investigated experimentally at low Reynolds numbers (50000 and 75000) and various angles of attack on the aerofoil using force measurement, pressure measurement and smoke-wire flow visualization techniques. The experiments of resonance characteristics of test section of the wind tunnel showed that the frequencies used for acoustic control were not equal to the peak (resonance) frequencies of the wind tunnel test section. The experimental results of acoustic control showed that when acoustic excitation of a certain frequency was applied, the length of the laminar separation bubble was shortened owing to the energy added to the flow by acoustic excitation. Because of the shortened laminar separation bubble, coefficient of lift was increased. Furthermore, at the stall angles the separated flow was forced to reattach to the surface of the aerofoil, so the stall angle was increased from 12 degrees to 17 degrees and maximum coefficient of lift was increased from 1.16 to 1.24 at Re=50000 and from 13 degrees to 18 degrees and maximum coefficient of lift was increased from 1.18 to 1.34 at Re=75000

An experimental study of acoustic disturbances effect on laminar separation bubble and transition over an aerofoil at low reynolds number

In this study, the effect of parallel acoustic excitation on laminar separation bubble over NACA2415 aerofoil and stall characteristics of the aerofoil were investigated at Re=50x103 and at various angles of attack. A sound source connected to a signal generator and an audio amplifier was placed in front of the wind tunnel to be parallel to the aerofoil. The amplitude of the sinusoidal sound wave was kept constant at 60 dB to determine the effects of varying frequencies from 70 Hz to 1100 Hz. In the experiments, an external three component load-cell system for force measurements, a scanivalve unit and a pressure transducer for pressure measurements and smoke-wire technique for flow visualization were used. The pressure measurement experiments showed that at the range of 200 Hz to 850 Hz the separated flow was reattached at the angle of attack of 15° and the laminar separation bubble was shortened at the angle of attack of 8° The shortened laminar separation bubble was seen clearly from some-wire flow visualization photos. Furthermore, the stall angle was delayed from αs=12° to αs=16° and CLmax was increased from 1.2 to 1.56 with acoustic excitation of 350 Hz. © 2012 by the American Institute of Aeronautics and Astronautics, Inc

Acoustic Control of Flow over NACA 2415 Airfoil at Low Reynolds Numbers

In this study, the effects of acoustic excitation frequency on flow over an NACA 2415 airfoil were determined, and all of the experiments were done both with and without the presence of the acoustic excitation. The acoustic excitation was applied for a range of angles of attack (0 degrees-25 degrees) and Reynolds numbers of 50,000, 75,000, 100,000, 150,000, and 200,000. To examine the effects of acoustic excitation on the flow, force measurements, pressure measurements, hot-wire anemometry, smoke-wire flow-visualization, and particle image velocimetry techniques were employed. The results indicated that for stall and some limited poststall angles of attack of the acoustic excitation having a frequency in a certain range forced the separated shear layer to reattach to the surface of the airfoil. As the Reynolds number increased, the effective excitation frequency increased, but the range of Zaman number [St/(R-1/2)] was the same. With the acoustic excitation, the stall angle was delayed from 12 degrees to 16 degrees at R = 50,000, and there was a 30% and 50% increase on the maximum value of the lift coefficient and the ratio of the lift and drag forces, respectively. Moreover, the stall angle was delayed from 13 degrees to 17 degrees at R = 75,000, from 15 degrees to 18 degrees at R = 100,000, from 15 degrees to 17 degrees at R = 150,000. Furthermore, it was concluded that acoustic excitation shrunk laminar separation bubble, and an effect of the acoustic control on the separation bubble decreased as the Reynolds number increased. (C) 2016 American Society of Civil Engineers

Numerical investigation of flow on NACA4412 aerofoil with different aspect ratios

In this study, the flow over NACA4412 was investigated both numerically and experimentally at a different Reynolds numbers. The experiments were carried out in a low speed wind tunnel with various angles of attack and different Reynolds numbers (25000 and 50000). Airfoil was manufactured using 3D printer with a various aspect ratios (AR = 1 and AR = 3). Smoke-wire and oil flow visualization methods were used to visualize the surface flow patterns. NACA4412 aerofoil was designed by using SOLIDWORKS. The structural grid of numerical model was constructed by ANSYS ICEM CFD meshing software. Furthermore, ANSYS FLUENT™ software was used to perform numerical calculations. The numerical results were compared with experimental results. Bubble formation was shown in CFD streamlines and smoke-wire experiments at z / c = 0.4. Furthermore, bubble shrunk at z / c = 0.2 by reason of the effects of tip vortices in both numerical and experimental studies. Consequently, it was seen that there was a good agreement between numerical and experimental results