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"In the framework of the design of Cisadane Cable Stayed Bridge, a wind tunnel testing on scaled model has been conducted lo observe its aerodynamic forces. The wind tunnel which is used for test, was a low speed wind tunnel.The test results are the coefficient Ci, Cd and Cm. The coefficients can be used lo calculate the load of the structure, the lift Force and the pitching moment. Based on the test results, shape improvement of the proposed bridge deck is also considered."

"As an initial analysis,numerical simulation has more advantages in saving time and costs regarding experiments. For example, variations in flowconditions and geometry can be adjusted easily to obtain results. Computationalfluid dynamics (CFD) methods, suchas the k-ε model, renormalizationgroup (RNG) k-ε model and reynolds stress model (RSM), are widely used toconduct research on differentobjects and conditions. Choosing the appropriate model helps produce and developconstant values.Modeling studies as appropriate, i.e., in the turbulent flow simulation in the windtunnel, isdone to get a more accurate result. This study was conducted by comparing the results ofthe simulation k-ε model, RNG k-ε model and RSM, which is validated by the testresults. The air had adensity of 1,205 kg/m3, a viscosity of 4×10-5 m2/sand a normal speed of 6 m/s. By comparing the simulation results of the k-ε model, RNG k-ε model and RSM, which isvalidated by the test results, the third turbulencemodel provided good results to predict the distribution of speedand pressure of the fluid flow in the wind tunnel. As for predicting theturbulent kinetic energy, turbulent dissipation rate and turbulent effectiveviscosity, the k-εmodel was effectivelyused with comparable results to the RSM models."

"As an initial analysis, numerical simulation has more advantages in saving time and costs regarding experiments. For example, variations in flow conditions and geometry can be adjusted easily to obtain results. Computational fluid dynamics (CFD) methods, such as the k-? model, renormalization group (RNG) k-? model and reynolds stress model (RSM), are widely used to conduct research on different objects and conditions. Choosing the appropriate model helps produce and develop constant values. Modeling studies as appropriate, i.e., in the turbulent flow simulation in the wind tunnel, is done to get a more accurate result. This study was conducted by comparing the results of the simulation k-? model, RNG k-? model and RSM, which is validated by the test results. The air had a density of 1,205 kg/m3, a viscosity of 4×10-5 m2/s and a normal speed of 6 m/s. By comparing the simulation results of the k-? model, RNG k-? model and RSM, which is validated by the test results, the third turbulence model provided good results to predict the distribution of speed and pressure of the fluid flow in the wind tunnel. As for predicting the turbulent kinetic energy, turbulent dissipation rate and turbulent effective viscosity, the k-? model was effectively used with comparable results to the RSM models."

"ABSTRAKKondisi perkotaan modern dengan jumlah kepadatan penduduk yang meningkat sedang mengalami banyak permasalahan. Salah satu dari banyak permasalahan ini adalah naiknya jumlah kendaraan yang memenuhi volume jalanan. Untuk mengatasi masalah tersebut, banyak proposal solusi yang diajukan dan salah satunya adalah pembuatan kendaraan terbang. Konsep penggunaan kendaraan terbang merupakan solusi yang populer diajukan dan bahkan sudah diriset semenjak tahun 1926. Sayangnya, ketertarikan publik terhadap konsep ini tidak dapat ditimbalbalikan oleh idustri otomotif ataupun aeronautik, sehingga pengembangan mobil terbang tidak berjalan signifikan selama 50 tahun terakhir. Dalam satu dekade terakhir ini, pengembangan mobil terbang kembali bangkit lagi dengan munculnya pembuatan model-model prototype seperti aeromobil dan VTOL milik uber. Sebagai salah satu instansi yang terlibat dalam pengembangan kendaraan modern, tim riset kendaraan mutakhir Universitas Indonesia juga ikut berperan dengan target untuk memproduksi kendaraan yang serupa. Salah satu aspek yang turut membantu riset ini adalah penggunaan terowongan angin untuk menghitung gaya-gaya aerodinamika pada mobil terbang. Skripsi ini membahas tentang faktor-faktor yang mempengaruhi perhitungan gaya aerodinamika pada model mobil terbang berdasarkan perbandingan dari hasil simulasi dengan Wind Tunnel Test. Penelitian ini merupakan penelitian kuantitatif dengan desain deskriptif. Hasil dari penelitian ini menunjukan performa jarak take-off sepanjang 415 m dan landing sepanjang 329 m.

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ABSTRACTThe condition of todays modern urban cities with increasing population density is under the weight of various problems. One of these problems is the contiously increasing number of vehicles that fills the traffic spaces. To resolve that problem, many proposals containing various solutions are submitted and one of it is to create a flying vehicle. The idea of using flying vehicles has been one of popular interest and the research even dates back to 1926. Unfortunately, public interest of this idea has not been mutually responded by aeronautics and automotive industries, thus the development of flying cars has been stale for the past 50 years. In the last decade, flying car development has risen again with creation of prototype models such as the aeromobil and VTOL by uber. As one of the institutes that also take part in researching modern vehicles, the advanced vehicle research team of Universitas Indonesia also plays a role with a target to produce a similar vehicle. One of the aspects that helps this research is the use of wind tunnels to calculate the aerodynamic forces of flying car. This thesis covers the factors that affects the measurements of aerodynamic forces on flying car model based on comparison of simulation results using wind tunnel testing. This research is a quantitative type with descriptive design. The results of this research shows take-off performance distance of 415 m and landing distance of 329 m."

"Pada era globalisasi ini, mesin-mesin yang dibuat oleh manusia  telah mendominasi kebutuhan sehari-hari. Salah satu mesin yang paling umum adalah mobil. Kemacetan telah menjadi masalah krusial yang dihadapi kota-kota besar di seluruh dunia selama bertahun-tahun terakhir. Tak hanya berakhir pada permasalahan tersebut, namun kemacetan juga menimbulkan efek domino kepada permasalahan lainnya seperti produktivitas, sebagaimana waktu yang dihabiskan untuk perjalanan tanpa mengasilkan sesuatu yang produktif; polusi, akibat waktu yang dihabiskan untuk perjalanan dengan mesin mobil yang menyala berarti proses pembakaran bahan bakar kemudian berujung pada polusi; dan permasalahan-permasalahan lainnya. Adalah sebuah solusi yang ditawarkan, bagi beberapa perusahaan dunia yang sudah memulai namun masih dalam tahap perkembangan. Solusi tersebut adalah mobil terbang. Studi ini adalah salah satu bentuk mewujudkan solusi tersebut menjadi kenyaataan. Skripsi ini membahas tentang  diagram polar, sebagai bentuk ilustrasi dari perbandingan koefisien gaya angkat (C_L) dan koefisien gaya hambat (C­_D). Nilai maksimum perbandingan digunakan sebagai penentu rancangan desain. Hasil ini diambil berdasarkan pengujian terowongan angin. Analisis drag polar berujung pada nilai L/D maksimum yang diperoleh sebesar 7.449 pada saat sudut serang berada pada posisi 12^o. Dengan pemerolehan nilai ini, dapat dihitung nilai gaya dorong yang diperlukan. Gaya dorong yang diperlukan dengan pendekatan analitis sebesar 1 702.246 N dan pendekatan grafis sebesar 33.823 N.

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In this globalization era, human made machines dominate the daily needs. One of the most accustomed machine is car. Thus, traffic jam is a major problem big cities all over the world have been dealing with these past years. And it does not end there. Traffic has the domino effects to some of other problems, like productivity, as the time spent on the road doing nothing productive is increasing means less productive results; pollution, because the longer time on the road mena smore fuel is burnt thus more pollution; and many more. There is one solution offered, that several companies in the world have created but still under development. That one solution is flying car. This study is one proof to make the solution comes true.

This thesis covers entirely about polar diagram, as an illustration for the ratio of lift coefficient (C_L) and drag coefficient (C_D). The maximum value of this comparison is a crucial number for the determination of the overall design. The values are collected based on the wind tunnel testing. This research is a quantitative type with descriptive design. The polar diagram analysis shows that the maximum value of the ratio is 7.449 at 12^o of angle of attack. With the value of maximum lift-to-drag ratio, the thrust required for steady level flight is calculated. The thrust required with analytical approach reaches 1 702.246 N and the graphical approach result is 33.823 N."