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"Bahaya kebakaran menjadi salah satu aspek keselamatan yang harus diperhatikan dalam mendesain dan mendirikan bangunan. Jika terjadi kebakaran, kerugian bukan hanya dari sisi materiilnya saja, melainkan juga dari segi sisi nonmateriil, seperti cedera, cacat, bahkan kematian. Pada penelitian pemodelan ini, simulasi dibuat dengan software FDS (NIST), sistem tirai kabut air dengan skala laboratorium dibuat untuk mempelajari pengaruhnya terhadap perubahan distribusi temperatur ruangan, yaitu ruangan yang tidak menggunakan kabut air dan menggunakan kabut air. Dari hasil pemodelan, adanya tirai kabut air mempengaruhi persebaran panas yang terjadi di dalam ruangan. Selain itu, pemilihan single mesh dengan 3 (tiga) ukuran grid yang berbeda dalam input dilakukan untuk mengetahui pengaruhnya terhadap keakuratan hasil output dari parameter-parameter yang akan diukur. Beberapa variabel di atas, selain berpengaruh terhadap perubahan temperatur di dalam ruangan, juga berpengaruh terhadap aliran asap yang berasal dari pool fire.

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Fire hazard is one of the aspects that has to be considered when designing and constructing buildings. Fire, will not only result in material losses but also immaterial losses, such as injury, disability or even death. In this modelling, the simulation software created by FDS (NIST), a laboratorium scale room was made to study the effect of water mist curtain system. In this case we compare 2 rooms, one room with water mist curtain and the second room without water mist curtain.

From the modeling results, we will see that the existance of water curtain affects the heat flow in the compartment. The reason of the selection of a single mesh with 3 (three) different grid sizes when inputting the data for the simulation, is to study and determine the accuracy of the output parameter. Some of the variables input above, are not only affecting the change of the room temperature, but also affecting the flow of smoke from the pool fire in the compartment."

"Penelitian mengenai mikroalga bukanlah hal yang baru dan sudah dilakukan oleh banyak peneliti. Saat ini, mikroalga telah terbukti dapat dimanfaatkan dalam berbagai bidang, mulai dari sebagai sumber pangan, kesehatan, kecantikan, biomaterial, hingga energi. Potensi mikroalga dan luasnya bidang pemanfaatan mikroalga menyebabkan biomassa mikroalga dibutuhkan dalam jumlah banyak. Untuk memperoleh biomassa mikroalga yang memadai, maka diperlukan desain fotobioreaktor yang tepat. Aspek desain yang diteliti pada penelitian ini adalah aspek pencampuran zat karena aspek tersebut merupakan salah satu aspek yang berpengaruh secara dominan dalam produksi biomassa mikroalga. Pencampuran berpengaruh terhadap pertumbuhan mikroalga karena melibatkan distribusi nutrisi yang diperlukan untuk pertumbuhan mikroalga. Mikroalga yang digunakan pada penelitian ini adalah Chlorella vulgaris. Pada penelitian ini, penulis membandingkan produksi biomassa Chlorella vulgaris pada fotobioreaktor kolom gelembung dengan pencahayaan internal dengan tiga variasi laju alir udara yang berbeda, yaitu 8, 6, dan 4 L/menit. Kemudian, dilakukan pula analisis kandungan pigmen, lipid, dan protein untuk mengetahui kelayakan fotobioreaktor yang digunakan. Penelitian ini bertujuan untuk meningkatkan produksi biomassa mikroalga C. vulgaris melalui pengaturan laju alir udara. Didapatkan bahwa penggunaan laju alir udara 8 L/menit dengan kLa CO2 0,0062451 /menit dan ug 0,0194120 m/jam menghasilkan produksi dan produktivitas biomassa C. vulgaris yang paling tinggi yaitu produksi biomassa 0,345828 g/L, produktivitas biomassa per hari 0,1153 g/L.hari dan produktivitas biomassa per energi input 0,2180 g/W.hari.

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Research on microalgae is not a new thing nowadays and has been conducted by many researchers. The utilization of microalgae potentials has been proven in many fields, in example food, health, cosmetic, biomaterial, and energy. The potential of microalgae and its broad field of utilization caused the need of microalgae biomass. In order to obtain satisfying amount of microalgae biomass, the design of photobioreactor for cultivating microalgae should be considered appropriately.

Design aspects considered in this research is the aspect of mixing, because mixing aspect can alter the production of microalgae biomass. Microalgae Chlorella vulgaris is used in this research.

In this research, production of microalgae biomass in internally illuminated bubble column photobioreactor with three different variation of air flow rate that are 8, 6, and 4 L minute are compared. The pigment, lipid, and protein content are also analyzed to test the feasibility of the photobioreactor used in this research.

The objective in this research is to determine the air flow rate that gives optimum yield of microalgae biomass. From this research, air flow rate of 8 L minute with kLa CO2 0.0062451 minute dan ug 0.0194120 m hour gives the maximum biomass production and biomass productivity of C. vulgaris that are 0.345828 g L of biomass production, 0.1153 g L.day of biomass productivity per day and 0.2180 g W.day of biomass productivity per energy input."

"ABSTRAKThis paper is an attempt at a systematic approach to the flow field analysis in the case of air flowing through a straight channel with a circular bump. The results of the authors own experimental measurements are compared to those obtained by means of both an in house and a commercial CFD code. Apart from the RANS method, which is commonly used in engineering applications, a decision was made to use the URANS and LES methods, which are available both in the in house academic code and in the commercial program. The comparison between the calculation results is performed using what is referred to as the numerical Schlieren image, which for the RANS calculations is compared to the Schlieren image obtained from experimental testing."

"Gasification is a thermo chemical process for converting solid fuel such as coal, wood and other biomass into fuel gas that consists of the components CO, H2, CH4, CO2 and N2. Gasification technology is increasingly in demand due to oil fuel price is more expensive. And of course gasification technology must also be able to maintain continuity of Producer gas if want to compete in the world of industry. The research objective was to study the characteristics of gasification with coconut shell fuel. Type of gasification reactors that used is a downdraft fixed bed gasifier. This study aimed to obtain the temperature profile in the gasifier during operation, flow rate, flame visualization of combustion of producer gas and calculation aspects thermodynamic. The purpose of the above studies carried out to operating the gasifier for 12 hours with the primary air flow rate and suction blower that optimum. Gasification process use coconut shell with Equivalence ratio 0.423. The best efficiency of the current study scored 78.8 %; LHV from producer gas acquired 1070.49 kcal/m3."

"Properties of air flow passing out from rotary desiccant dehumidifier can be analyzed by either experimental or theoretical method in this case an experiment method was selected using Lithium Chloride (LiCl) as a desiccant. The flow rate of air at the input is varying for process air and regeneration air, and the moisture content at process air input also adjusted by using a water sprayer.

The data consisting of dry and wet bulb temperature of air is to be collected in order to find wet air properties, and flow rate of wet air flowing through the humidifier. The result of this experiment gives curves denoting properties of the outlet process air at the room temperature of 25°C These curves then can be used as a comparable data for characteristics of various dehumidifiers."

"Udara merupakan gas yang tersedia pada alam semesta. Udara dapat berubah seiring dengan perbedaan kecepatan yang terjadi. Oleh karena itu, pada penelitian ini terdapat suatu box simulasi yang diasumsikan sebagai ruangan, aliran masuk dan keluar fluida yaitu udara, serta dinding penghambat aliran yang diletakkan di dalam box simulasi. Penelitian ini dilakukan dengan simulasi CFD yang bertujuan untuk mengetahui karakteristik pola aliran fluida dengan pendekatan dinamika fluida berdasarkan beberapa kecepatan masuk udara yang berbeda. Karakteristik pola aliran yang terjadi, kemudian dianalisa melalui grafik dan kontur yang terjadi dari hasil potongan.

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Air is a gas which available in universe. Air can change together with the velocity difference which consists. Hence, on this research there used simulation box is a chamber which assumes, air intake flow and outflow, and then flow wall inhibitor what put in the simulation box.

This research is using CFD simulation with purpose to know fluid flow characteristic with fluid dynamics approaching and based on the several different air intake velocity. Flow characteristic which happen, and analysis into graphic and contour from plane after then."

"Kualitas udara dalam ruangan di rumah sakit harus menjadi perhatian khusus karena pasien salah satu sumber pencemar mikroorganisme patogen ke udara yang dapat memicu persebaran infeksi nosokomial, maka dilakukan penelitian terhadap kualitas udara di salah satu rumah sakit di Depok, yaitu Rumah Sakit Tugu Ibu, untuk mengetahui konsentrasi mikroorganisme di udara. Sampel udara diambil menggunakan EMS Bioaerosol Sampler Single Stage Sampler dengan debit aliran udara sebesar 28,3 L/menit. Bakteri di udara diambil selama dua menit pada media Tryptic Soy Agar dan diinkubasi pada temperatur 35-37oC selama 24 jam, sementara itu jamur pada media Malt Extract Agar selama dua menit dan diinkubasi pada temperatur 25-29oC selama 48-72 jam. Koloni yang tumbuh dihitung sebagai colony-forming Units CFU/m3 . Hasil penelitian menunjukkan hasil angka kuman, temperature dan kelembaban udara dalam ruangan pada rentang 1.385-2.930 CFU/m3, 25-28oC dan 72-91 yang mana melebihi batas baku mutu KepMenKes No. 1204/MENKES/SK/X/2004. Hasil pengukuran konsentrasi diuji secara statistik menggunakan uji non-parametrik untuk menunjukkan korelasi dengan jumlah orang dan hasil menunjukkan korelasi sig< 0,05 pada konsentrasi bakteri dengan jumlah orang dan tidak menunjukkan korelasi sig > 0,05 pada konsentrasi jamur dengan jumlah orang. Berdasarkan pengukuran dan perhitungan, sebagian besar Bilangan Reynold lebih besar dari 2.000 yang mengindikasikan bahwa jenis aliran udara didominasi oleh aliran turbulen. Jumlah pertukaran udara sebagian besar kurang dari 4 kali/jam sehingga tidak memenuhi standar yang ditetapkan oleh ASHRAE 1999 . Besarnya konsentrasi bakteri dan jamur dipengaruhi oleh temperature, kelembaban udara, kecepatan udara, jenis aliran udara, dan pertukaran udara per jam. Sementara itu, jumlah orang sangat berpengaruh terhadap konsentrasi bakteri namun tidak berpengaruh terhadap konsentrasi jamur.

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Indoor air quality in hospital has to be considered because patients could be a source of pollutant and lead a nosocomial infection. Therefore, bioaerosol was measured in selected hospitals at city of Depok, which is Tugu Ibu Hospital. Air sampling was conducted by using EMS Bioaerosol Single Stage Sampler and worked at a flowrate of 28.3 l min. Airborne bacteria were collected for two min on Tryptic Soy Agar and then incubated at 35 37oC for 24 h, while fungi on Malt Extract Agar for two min and then incubated at 25 29oC for 48 72 h. The colonies were counted as colony forming units CFU m3 . The result showed that indoor air bacteria and fungi concentrations, air temperature and humidity with the range approximately between 1,385 2,930 CFU m3, 25 28oC and 72 91 , respectively. All the numbers have exceeded the quality of standards by Ministry of Health Decree No. 1204 MENKES SK X 2004. Spearman rank correlation showed strong correlation sig 0.05 between indoor air bacteria concentrations and number of visitors and no correlation sig 0.05 between indoor air fungi concentrations and number of visitors. Based on measurements and calculations, Reynold numbers were mostly over 2,000, which indicated the indoor airflow dominated by turbulent flow. Air change rates were mostly less than 4 times hour and did not meet quality standards by ASHRAE 1999 . Indoor air bacteria and fungi concentrations were influenced by temperature, air humidity and velocity, type of airflow and air change rates. Meanwhile, number of visitors affected the concentration of bacteria but did not on fungi."