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Abstrak :
Perkembangan ilmu pengetahuan dan penelitian saat ini berfokus pada pembuatan nanoteknologi. Salah satu nanoteknologi yang sedang dikembangkan saat ini adalah nanofluida yang merupakan salah satu jenis thermal fluida dan dapat dijadikan sebagai media pendingin. Dalam penelitian ini, thermal fluida dibuat melalui metode 2 tahap, yaitu pembuatan partikel karbon dari karbon arang batok kelapa dengan cara di Ball mill dan kemudian partikel karbon didispersikan dalam fluida berupa air distilasi dengan konsentrasi partikel 0.1%, 0.3% dan 0.5% yang kemudian ditambahkan surfaktan SDBS dengan konsentrasi 0%, 10%, 20% dan 30% untuk meningkatkan stabilitasnya, lalu di ultrasonifikasi. Thermal fluida tersebut kemudian digunakan sebagai media quench baja S45C yang diaustenisasi pada suhu 900°C untuk dilihat performanya. Dari penelitian yang dilakukan diketahui bahwa penambahan surfaktan SDBS dengan konsentrasi 10%, 20% dan 30% pada thermal fluida cenderung akan menurunkan konduktvitas termal dari thermal fluida dan nilai konduktivitas termal tertinggi diperoleh thermal fluida dengan konsentrasi karbon 0.1% tanpa penambahan surfaktan SDBS, yaitu 0.75 W/m°C. Sementara nilai kekerasan baja tertinggi didapat dengan meng-quench baja dengan media quench thermal fluida dengan konsentrasi karbon 0.3% tanpa penambahan surfaktan SDBS yaitu 57 HRC. ......Current scientific and researches developments focuses on the manufacture of nanotechnology. One of the nanotechnology that being developed is nanofluids which is a type of thermal fluids and can be uses as cooling media. In this research, the thermal fluid is synthesized using a 2-step methods, which is carbon particle that synthesized by ball milling the coconut shell charcoal carbon and then dispersing the carbon particle with concentrations of 0.1%, 0.3% and 0.5% into distilatted water which was then added with SDBS surfactant with concentrations of 0%, 10%, 20% and 30% to increase their stability, then ultrasonication was performed. The Thermal fluids was the used as quench medium for S45C steel that was being austenitizing at temperature of 900°C to observe the performance. From the research conducterd, it is known that the addition of SDBS surfactant with concentrates of 10%, 20% and 30% will tend to decrease the thermal conductivity of thermal fluids and the highest thermal conductivity is approached by thermal fluid with 0.1% carbon concentration without SDBS surfactant added, which value is 0.75 W/m°C. Meanwhile, the highest hardness value is approache by the steel that being quenched using thermal fluids with 0.3% carbon concentration without surcactant added as quench medium which value is 57 HRC.

Abstrak :
In recent developments in the area of thermofluid technologies, active flow control has emerged as an interesting topic of research. One of the latest methods, which will be discussed in this paper, is the application of a plasma actuator. Plasma actuation is achieved by conducting a high-voltage electric current through an actuator device. Our research was specifically conducted to discover its effect on the reduction of the drag coefficient, with Ahmed Body the experimental object put inside a suction-flow wind tunnel with varying inputs of flow velocity. The plasma actuator device was run with an A.C. power supply and installed in three different placement configurations on the aerodynamic model to determine which most optimally affected the aerodynamic drag, while the drag coefficients were acquired via the use of a load cell installed as the harness for the aerodynamic model inside the tunnel. The results of the experiments include that the optimal configuration of the actuator placement was on the leading edge, the optimal wind flow velocity of the experiment, which was essential for the actuation to be observed, was at 1.7 m/s, and the resulting drag reduction percentage, as a result of induced flow, was 22% of the initial drag coefficient.

Abstrak :
This Handbook provides readers with the current cutting edge of multiphase flow technology. It reviews the rapid development of multiphase flow technology, demonstrates the latest development of the technology, and showcase the very latest applications. It provides readers with comprehensive updated reference information covering theory, modelling and numerical methods, design and measurement, and new applications in multiphase flow systems. The Handbook consists of three parts or volumes: 1. Theory: describes the fundamentals including the concepts and definitions of multiphase flows. Classifications of multiphase flows. Basic understanding of different length scales involved – micro/nano, meso and macro. Treatment of such flows by different solution frameworks. 2. Modelling and Measurement: covers both classical and state-of the-art measurement and modelling approaches to resolve different classifications of multiphase flows. 3. Applications: highlights the very latest applications of measurement and modelling approaches in tackling different classification of multiphase flows in a variety of natural, biological and industrial systems and different length scales.