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"The book begins with a synopsis of the fundamentals aspects of fluid mechanics to give the reader the essential background to address the proceeding chapters. Then the fundamental elements of vortex dynamics will be discussed, explaining the conditions for their formation and the rules governing their dynamics. The main equations are accompanied by mathematical models. Cardiovascular vortex formation is first analyzed in physiological, healthy conditions in the heart chambers and in the large arterial vessels. The analysis is initially presented with an intuitive appeal grounded on the physical phenomena and a focus on its clinical significance.In the proceeding chapters, the knowledge gained from either clinical or basic science literature will be discussed. The corresponding mathematical elements will finally be presented to ensure the adequate diligence. The proceeding chapters ensue to the analysis of pathological conditions, when the reader may have developed the ability to recognize normal from abnormal vortex formation phenomenon. Pathological vortex formation represents vortices that develop at sites where normally laminar flow should exist, e.g. stenosis and aneurisms. This analysis naturally leads to the interaction of vortices due to the surgical procedures with respect to prediction of changes in vortex formation. The existing techniques, from medical imaging to numerical simulations, to explore vortex flows in the cardiovascular systems will also be described. "

"Written by internationally eminent experts in cardiovascular imaging, this volume provides state-of-the-art information on the use of MRI and CT in the assessment of cardiac and vascular diseases. This third edition, now in four-color, reflects recent significant advances in cardiovascular MRI technology and the continuing emergence of multi-detector CT as an important diagnostic modality, particularly for ischemic heart disease. Seven new chapters have been added including chapters on anatomy, cardiovascular MR in infants/​children, assessing myocardial viability, risk assessment in ischemic heart disease and MR guidance."

"This paper presents a baseline study of the development of turbulent flow separation for controlling aerodynamic phenomena, especially in the design of the vehicle body. The purpose of this study was to analyze the performance of synthetic jet actuators (SJAs) as one of the tools that can be used in reducing the flow controller separation area on the bluff body model of the vehicle. To get maximum results in the performance of the SJA, this research starts with characterizing the actuator, including changes in the shape of the cavity and orifice diameter. Cavity shapes tested were half-ball (B), tube (T) and cone (K), while orifice diameters of 3, 5 and 8 mm were examined. The study was conducted using both computational and experimental approaches. Results from both types of research methods were compared and displayed in graphical form. These results serve as a reference for determining future research. The experimental results, in the form of the flow rate for each type of cavity, determined the ability of different cavity conditions to form vortex rings, whereas in CFD simulations, the formation of vortex rings was demonstrated via the visualization of flow contours. Vortex rings occurred in cavity conditions B3, T3, T5, K3 and K5. Vortex rings were not formed on any type of cavity with an orifice having a diameter of 8 mm."

"This paper provides an explanation of the effects of cavity shape and frequency excitation to the vortex formation of the synthetic jet. In order to get comprehensive results, this study will be conducted by both computational and experimental methods.The experiment method prepared by applying hotwire probe on the center point of the synthetic jet orifice, so from here the researcher get the Ux (average airflow velocity from membrane movement)in a low voltage signal, then the data will be transferred to analog data converter within the record speed 10.000 data/s. The cavities shapes that will be applied are half-sphere, tubes, and conical. The diameter varieties of the orifice are 3 mm, 5 mm and 8 mm. the simulation is started by utilizing the flow rate data from the experiment which can be put in the simulation boundary condition. Furthermore, from visual data of flow contour from CFD simulation the qualities vortex ring formation from SJA can be determined. Based on this research result, the formation of vortex ring occurs at the configuration B3, T3, T5, K3 and K5 of the SJA. Meanwhile, the other types of the synthetic jet cavity which have 8 mm of orifice diameter is not producing the vortex ring."

"Telah berhasil dibangun pembersih permukaan substrat menggunakan metode vortex plasma yang mampu membersihkan kaca preparat yang semula memiliki sifat hidrofobik menjadi hidrofilik setelah dilakukan proses pembersihan. Sifat hidrofobik dan hidrofilik dari suatu permukaan digunakan untuk menyatakan kebersihan permukaan secara kualitatif. Pengamatan sudut kontak dari air yang diteteskan dengan metode sessile drop menyatakan kebersihan permukaan secara kuantitatif. Vortex plasma yang dihasilkan oleh sebuah kumparan sebagai penghasil medan magnet dan elektroda plat tembaga yang diberi beda potensial listrik. Medan magnet yang dihasilkan oleh kumparan dengan 320 lilitan yang diberikan arus DC sebesar 1,92 A adalah 5,42 mT. Dengan durasi waktu pembersihan 10 menit dengan tekanan 2000 micron dapat menghasilkan rata-rata sudut kontak 8 derajat, Sedangkan penggunaan perantara gas argon untuk proses pembersihan mampu menghasilkan rata-rata sudut kontak sebesar 4 derajat. Sudut kontak yang dihasilkan semakin mengecil seiring dengan lamanya waktu pembersihan, baik dengan gas argon maupun tanpa gas argon. Pengujian ini membuktikan bahwa gas argon lebih efektif untuk proses pembersihan dengan vortex plasma.

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A substrate surface cleaner has been successfully built using the plasma vortex method which is able to clean preparate glass which originally had hydrophobic properties to become hydrophilic after the cleaning process. The hydrophobic and hydrophilic properties of a surface are used to describe the surface cleanliness qualitatively. Observation of the contact angle of the water dripped by the sessile drop method states the surface cleanliness quantitatively.Vortex plasma produced by a coil as a generator of the magnetic field and a copper plate electrode which is given an electric potential difference of 30KV. The magnetic field produced by a coil given a DC current of 1.92 A is 5.42 mT. With a cleaning time of 10 minutes with a pressure of 2000 microns, it can produce an average contact angle of 8 degrees, while the use of argon gas intermediary for the cleaning process is able to produce an average contact angle of 4 degrees. The resulting contact angle decreases with the duration of cleaning time, both with argon gas and without argon gas. This test proves that argon gas is more effective for the cleaning process with vortex plasma."

"Vortex methods have emerged as a new class of powerful numerical techniques to analyze and compute vortex motion. This book addresses the theoretical, numerical, computational, and physical aspects of vortex methods and vortex motion. Vortex phenomena in fluid flows and the experimental, theoretical, and numerical methods used to characterize them are discussed in reviews by leading experts. Extensive photographs and sample computer graphics are provided. The development of large vortex structure in fluid flow is responsible for some of the most fascinating aspects of fluid dynamics, such as mixing, shearing, transport, and instability. Such issues arise in a variety of flow regimes, ranging from fundamental mathematical questions in laminar, transitional, and turbulent flow to sophisticated engineering settings and devices."

"Producer gas hasil gasifikasi biomassa masih mengandung pengotor berupa abu. Pembersihan producer gas dilakukan menggunakan cyclone separator. Sebuah model cyclone separator konfigurasi standar 2D2D berdiameter 150 mm telah dibuat. Tiga variasi panjang (3/8 D; 5/8 D; 1 D) dan tiga variasi diameter (35; 70; 85) vortex finder digunakan untuk mengetahui pengaruhnya terhadap performa cyclone. Eksperimen dan simulasi CFD menggunakan Ansys Fluent telah dilakukan. Simulasi CFD bertujuan untuk mengetahui profil kecepatan didalam cyclone separator. Hasil eksperimen menunjukkan semakin panjang vortex finder, collection efficiency semakin tinggi. Hasil simulasi CFD mendukung kesimpulan hasil eksperimen. Didapatkan dimensi vortex finder optimum dengan diameter 35 mm (1/4 D) dan panjang 1D (150 mm).

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Producer gas produced from biomass gasification still contain particulate ash. Producer gas is cleaned by use of cyclone separator. A cyclone separator model with 2D2D standard configuration with diameter150 mm was made. Three variation of length (3/8 D; 5/8 D; 1 D) and three variation of diameter (35; 70; 85 mm) of vortex finder are used to identify their influence on cyclone performance. Experimental study and CFD Simulation using Ansys Fluent were performed. CFD simulation goal is to determine the velocity profile inside cyclone separator. Experimental results shows that increasing vortex finder length can increase the collection efficiency. The optimum vortex finder dimension is 35 mm (1/4 D) in diameter and 1 D (150 mm) in length."

"ABSTRAKPenelitian ini akan membahas mengenai pengaruh variasi frekuensi danbentuk gelombang pada pembentukan cincin vorteks oleh aktuator jet sintetik.Variasi frekuensi yang digunakan dalam percobaan yaitu 80 Hz sampai dengan 200Hz, sedangkan variasi bentuk gelombangnya adalah bentuk gelombang sinusoidal,square, dan triangle. Bentuk cavity dari aktuator adalah kerucut dengan diameterorifis 3mm, 5mm, dan 8mm. Kriteria pembentukan cincin vorteks yang digunakandalam penelitian ini adalah kriteria yang dipublikasikan oleh Ryan Holman dkkuntuk jet sintetik 2 dimensi yaitu 1⁄𝑆𝑟 = 𝑅𝑒⁄𝑆2 > 1. Pengambilan dataeksperimen dilakukan pada mulut orifis (𝑥⁄𝐷 = 0 dan 𝑦⁄𝐷 ≈ 0) denganmenggunakan Constant Temperature Anemometer (CTA) dengan data rate 60,000data dalam 2 detik. Sedangkan data simulasi diperoleh dengan menggunakansoftware Fluent 6.2.36 dengan menggunakan model turbulensi Reynolds StressModel. Dari data yang diperoleh kemudian diolah untuk dimasukkan dalam kriteriapembentukan cincin vorteks. Dari hasil pengolahan data, diddaptkan rentangfrekuensi optimum serta bentuk gelombang yang paling baik untuk aktutor jetsintetik dalam pembentukan cincin vorteks.

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ABSTRACTThis study will discuss the influence of variations in frequency andwaveform on the formation of vortex rings by synthetic jet actuators. Excitationfrequency variation used in the experiment is 20 Hz to 200 Hz, with a variation ofthe waveform is sinusoidal, square, and triangle. The shape of the actuator?s cavityis conical with orifice diameter of 3mm, 5mm and 8mm. Criteria for the formationof vortex rings used in this study are the criteria published by Ryan Holman et alfor 2 dimensional synthetic jet 1/Sr = Re/S ^ 2> 1. The study was conductedpremises using experimental and computational methods. Experimental data iscapured on the mouth of the orifice (x/D = 0 and y/D≈0) using the ConstantTemperature Anemometer (CTA) with a data rate of 60,000 data in 2 seconds.While the simulation data obtained using Fluent software 2.6.36 by using ReynoldsStress Model as the turbulence model. Data which have obtained is then processedfor inclusion in the criteria for the formation of vortex rings. From the dataprocessing, obtained optimum frequency range and waveform for the synthetic jetactuator in the formation of vortex rings.;;"

"Vortex tube sebagai alat spot cooling memiliki kelebihan di dalarn mekanisme kerjanya yang sederhana dan relatif murah. Penelitian ini bertujuan untuk mengetahui sejauhmana pengaruh beberapa kontigurasi pada arah aksial ternadap kemampuan penurunan temperatur dan kapasitas pendinginan maksimum yang dapat dicapai, sehingga diharapkan nantinya dapat dirancang sebuah vortex tube dengan menggunakan kombinasi penambahan inlet baik secara radial maupun aksial, dengan performa yang lebih baik.Penelitian ini dilakukan dengan melakukan eksperimen unjuk kerja helical vortex generator pada vortex tube X-1 FTUI. Modifikasi dilakukan pada bagian vortex chambernya, yaitu dengan tidak menggunakan tipe oritis yang memiliki konfigurasi inlet tangensial pada arah radial saja, tetapi digunakan 3 buah vortex chamber dengan konfigurasi lubang inlet tangensial θ 1 mm masing-masing sebanyak 1, 2 dan 3 buah, yang diposisikan secara aksial, menggunakan variasi tekanan udara masuk dari kompresor sebesar 9 dan 11 bar. Nilai yang diukur adalah temperatur udara keluar dari pipa dingin (Tc), temperatur keluar dari pipa panas (Thot), temperatur udara masuk dari kompresor (Tin), laju aliran massa serta tekanan statis pada sisi keluar hot tube maupun cold tube. Pengukuran parameter-parameter di atas dilakukan pada sepuluh variasi putaran katup jarum.Dalam pengujian dengan menambah lubang inlet pada arah aksial ini, di dapat penurunan temperatur maksimum sampai 21,5 °C, dengan temperatur minimum yang dioapai adalah 8 °C pada fraksi massa dingin 0,46 untuk penggunaan 2 Iubang inlet pada tekanan udara masuk 11 bar. Sedangkan pada penggunaan 3 lubang inlet, terjadi penurunan kinerja dalam hal penurunan temperatur jika dibandingkan dengan penggunaan 2 lubang inlet, dimana penurunan temperatur maksimum yang dapat dicapai adalah 18,3 °C dengan temperatur minimum 10 °C pada fraksi massa dingin 0,39 dan tekanan udara masuk 9 bar. Kenaikan tekanan udara masuk pada pengujian menggunakan 1 dan 2 inlet akan memperbesar pencapaian temperatur drop maksimumnya, tetapi akan berbeda untuk penggunaan 3 inlet, dimana kenaikan tekanan tersebut akan menurunkan kemampuan pencapaian temperatur drop maksimumnya.

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Vortex tube as a spot cooling device has some advantage in its low price and simple work mechanism. This research is intended to know its level of performance if some axially inlet configuration applied in the design of helical vortex generator X-1 FTUI, so in the end we can combine radial and axial configuration of inlet nozzle for better vortex tube performance.

The research is based on experimental method on vortex tube X-1 FTUI using 1, 2 and 3 inlet nozzle axially position with θ1 mm. Measured parameter are temperature at outlet of cold and hot tube, air mass tiow rate and static pressure at the outlet of both tube. Each parameter was measured simultaniously in ten different valve position.

As the result in this experiment, comparing 1, 2 and 3 inlet nozzle, maximum temperature drop was occurred when using 2 inlet nozzle. Lower performance happens when using 3 inlet, und the lowest performance occurred when using 1 inlet nozzle. The maximum temperature drop can be obtain in this experiment is 21,5 °C while using 2 inlet nozzle with coolest temperature is 8 °C."