Simulation of Spray Injection in the Pressurizer Using RELAP5

A modeling research using Relap5 to assess the pressurizer of a pressurized water reactor(PWR) power plant has been performed. The heater and water injection systems in the pressurizer system of the PWRare of greatimportance for system pressure control.The heater is designed to increase the pressure while the water sprayer injection is to perform depressurization. Most of studies conducted in the past mainly focused on determining the effects of nozzle spray design and droplet size using testing loops. The purpose of this simulation is to analyze the spray injection flow rate against the pressure characteristics of the pressurizer using RELAP5. Through this approach, the optimum injection flow rate of full scale plant pressurizer can be analyzed. The parameters investigated are pressure and temperature.In RELAP5, the pressurizer tank wasmodeled with six volume nodes and the heater was modeled by using heat structure. In the model, the sprayer takes water from the cold leg to inject it into the top of tank region.The resultsshowedthat the mass flow of about 4 kg/s is the mosteffectivevalueto limit pressure in the pressurizer to below 15.7 MPa. However, the flow rates of 8 kg/s and more cause overpressure. This simulation is usefulto complement the data related to the water flow rate injection systems of the pressurizer

Simulation of Spray Injection in the Pressurizer Using RELAP5

A modeling research using Relap5 to assess the pressurizer of a pressurized water reactor(PWR) power plant has been performed. The heater and water injection systems in the pressurizer system of the PWRare of greatimportance for system pressure control.The heater is designed to increase the pressure while the water sprayer injection is to perform depressurization. Most of studies conducted in the past mainly focused on determining the effects of nozzle spray design and droplet size using testing loops. The purpose of this simulation is to analyze the spray injection flow rate against the pressure characteristics of the pressurizer using RELAP5. Through this approach, the optimum injection flow rate of full scale plant pressurizer can be analyzed. The parameters investigated are pressure and temperature.In RELAP5, the pressurizer tank wasmodeled with six volume nodes and the heater was modeled by using heat structure. In the model, the sprayer takes water from the cold leg to inject it into the top of tank region.The resultsshowedthat the mass flow of about 4 kg/s is the mosteffectivevalueto limit pressure in the pressurizer to below 15.7 MPa. However, the flow rates of 8 kg/s and more cause overpressure. This simulation is usefulto complement the data related to the water flow rate injection systems of the pressurizer

Pengaruh Faktor Budaya, Sosial, Individu Dan Psikologis Terhadap Keputusan Konsumen Membeli Di Indomaret

This study aims are to investigate the influence of cultural factors, social factors, personal factors and psychological factors on purchase decision in Indomaret Surakarta. Analysis using multiple linear regression, F test, t test, test the coefficient of determination (R2). Multiple linear regression analysis showed that all variables figures obtained positive coefficient. The test results (F) indicates that the variable cultural factors, social factors, personal factors and psychological factors together influence the purchasing decisions in Indomaret Surakarta. T test results showed that the variables of individual factors and psychological factors significantly influence purchasing decisions while variable cultural factors and social factors do not significantly influence the purchasing decision. To test the R2 (coefficient of determination) indicates that the variable cultural factors, social factors, personal factors and psychological factors were able to explain the variability of the variable of 39.8%. While the remaining 60.2% is explained by other variables outside the model. Keywords: cultural factors, social factors, personal factors, psychological factors

Estimasi Pengaruh Desalinasi terhadap Temperatur Umpan Pembangkit Uap RDE

ESTIMASI PENGARUH DESALINASI TERHADAP TEMPERATUR Umpan PEMBANGKIT UAP RDE. Reaktor temperatur tinggi tipe HTGR telah dikembangkan dengan berbagai kapasitas daya dan dapat menghasilkan aplikasi listrik dan panas. Salah satu aplikasi panas adalah digunakan untuk desalinasi. Penelitian ini bertujuan untuk mengestimasi pengaruh desalinasi terhadap parameter operasi temperatur air umpan masuk ke dalam pembangkit uap RDE dengan menggunakan program ChemCAD. Parameter yang terkait dengan aplikasi panas tersebut adalah temperatur proses pada untai sistem pendingin sekunder. Oleh karena itu pengaruh terhadap temperatur umpan pembangkit uap perlu estimasi. Uap dari turbin ditentukan sebagai kondisi operasi dalam rentang variasi laju alir massa dan daya untuk desalinasi. Hal ini penting karena air umpan dari tangki dipengaruhi oleh aliran dari kondensor dan dari unit desalinasi. Sistem desalinasi menggunakan penukar panas untuk menguapkan air laut. Hasil estimasi menunjukkan untuk mencapai kondisi temperatur umpan pembangkit uap pada kisaran 140oC – 150oC maka dapat ditentukan dengan penggunaan laju alir massa uap 0,5 kg/s – 0,6 kg/s untuk kebutuhan desalinasi, adapun dayanya pada kisaran 0,3 MJ/s – 0,5 MJ/s. Diharapkan estimasi ini bermanfaat untuk kajian terhadap aplikasi panas untuk sistem desalinasi pada RDE. Selanjutnya kajian secara komprehensif kedepan sangat diperlukan

Simulation of Modified TRIGA-2000 with Plate-Type Fuel under LOFA Using EUREKA2/RR-Code

The TRIGA-2000 research reactor in Bandung, Indonesia, has operated for over 50 years. Recently, the problem of fuel availability arises, since its fuel is no longer produced. A modification of reactor core with new plate-type fuel has been suggested. The study of the neutronic assessment of plate-type fuel elements reactor core had been done. The next assessment that needed to be done was thermal-hydraulic analysis. The purpose of this study is to simulate the thermal-hydraulic characteristics of major parameters, such as reactor power, fuel cladding temperature, and departure from nucleate boiling ratio (DNBR) due to LOFA transient, using EUREKA2/RR code. During steady-state condition, downward flow forced convection mode for core coolant system is operated. The upward flow occurs when the natural circulation mode takes place. Hottest core channels temperature during LOFA conditions was considered. The reactor core was modeled as three channels, i.e., the hottest channel, the average channel, and the channel for control assemblies, respectively. The simulation was based on the steady-state condition of 2 MWt reactor power, cooling mass flow rate of 63.5 kg/s,and inlet coolant temperature to the core of35.5°C. The result shows that the hottest fuel cladding temperature does not cause a nucleate boiling. During LOFA, the residual heat was removed by natural circulation flow that occurred slowly. In order to have larger inertia force, provision of the flywheel in the shaft of primary coolant pump is suggested

Pupuk Organik Sebagai Subtitusi Pupuk Anorganik Menuju Pertanian Lada Perdu Organik

Penelitian dilaksanakan di kebun percobaan Pakuwon dari bulan Mei–Desember 2009. Rancangan penelitian yang digunakan adalah Rancangan Acak Kelompok pola Faktorial, Faktor pertama terdiri dari dua jenis lada hibrida LH 4-5-5 (V1) dan LH 6-2 (V2), serta Petaling 1 (V3) sebagai pembanding. Faktor kedua merupakan Paket teknologi, yaitu penggunaan dosis pupuk organik sebagai substitusi pupuk anorganik dengan lima tingkat komposisi media tumbuh campuran tanah dengan pupuk organik dan penggunaan dosis pupuk anorganik, yaitu: P0 = tanah 1 : pupuk organik 1 + pupuk anorganik 100 % SOP, P1 = tanah 1 : pupuk organik 2 + pupuk anorganik 80 % SOP, P2= tanah 1 : pupuk organik 3 + pupuk anorganik 60 % SOP, P3= tanah 1 : pupuk organik 4 + pupuk anorganik 40 % dan P4= tanah 1 : pupuk organik 5 + pupuk anorganik 20 % SOP. Jumlah tanaman setiap perlakuan sebanyak 5 tanaman dan diulang 3 kali , sehingga jumlah tanaman keseluruhan sebanyak 225 tanaman. Parameter yang diamati meliputi tinggi tanaman, jumlah cabang primer dan sekunder, lingkar pangkal batang, panjang ruas serta jumlah daun per cabang, serta analisis hara makro dan mikro dari masing-masing perlakuan media tanam. Hasil penelitian menunjukkan bahwa kebutuhan pupuk anorganik NPK-Mg pada tanaman lada perdu dalam pot pada awal pertumbuhan dapat disubstitusi dengan pupuk organik sampai 80 % dan kebutuhan pupuk anorganik hanya 20%. Lada hibrida LH 6-2 dan LH 4-5-5 memiliki peluang produktivitas lebih tinggi dibanding Petaling-1. Kombinasi perlakuan pemupukan dan varietas tidak menunjukkan pengaruh yang nyata terhadap pertumbuhan vegetatif lada perdu sampai umur 4 bulan, hal ini memberikan peluang budidaya lada perdu dengan sistem pot dapat dibudidayakan dengan sistem pertanian organik

Simulation of Spray Injection in the Pressurizer Using RELAP5

A modeling research using Relap5 to assess the pressurizer of a pressurized water reactor(PWR) power plant has been performed. The heater and water injection systems in the pressurizer system of the PWRare of greatimportance for system pressure control.The heater is designed to increase the pressure while the water sprayer injection is to perform depressurization. Most of studies conducted in the past mainly focused on determining the effects of nozzle spray design and droplet size using testing loops. The purpose of this simulation is to analyze the spray injection flow rate against the pressure characteristics of the pressurizer using RELAP5. Through this approach, the optimum injection flow rate of full scale plant pressurizer can be analyzed. The parameters investigated are pressure and temperature.In RELAP5, the pressurizer tank wasmodeled with six volume nodes and the heater was modeled by using heat structure. In the model, the sprayer takes water from the cold leg to inject it into the top of tank region.The resultsshowedthat the mass flow of about 4 kg/s is the mosteffectivevalueto limit pressure in the pressurizer to below 15.7 MPa. However, the flow rates of 8 kg/s and more cause overpressure. This simulation is usefulto complement the data related to the water flow rate injection systems of the pressurizer. Normal 0 false false false EN-US X-NONE X-NONE <![endif]-

Potensi Pengembangan Kemiri Sunan (Reutealis Trisperma (Blanco) Airy Shaw)di Lahan Terdegradasi

The Multiple Benefits of Developing Kemiri Sunan (Reutealis trisperma (Blanco) Airy Shaw) In Degraded LandKemiri sunan (Reutealis trisperma (Blanco) Airy Shaw) is one kind of vegetable oil crops that have great potential as a source of raw material for biodiesel. The productivity level that can reach 8-9 tons of crude oil, equivalent to 6-8 tons of biodiesel/ha/year make as a strategic commodity associated with government programs to find alternative sources of renewable energy. Development of renewable energy such as from vegetable oils of kemiri sunan is one of the alternatives in an effort to solve the deficit of energy for domestic use so that Indonesia can way out of the crush of the energy crisis. Lands that have been degraded in Indonesia continuously increasing both cause of the extent of natural factors and uncontrolled exploitation. On the other hand the development of this plants retricted by aviability of land. The research88 Volume 14 Nomor 2, Des 2015 : 87 - 101 studies have been conducted on the characteristics of plants, oil and biodiesel production, and adaptability in very broadly of Indonesian agro-ecosystem, this plant show well hopes besides as a source of raw material for biodiesel, it can also function as a conservation plant to reclaim marginal lands that have been degraded. In addition, the development of kemiri sunan on degraded land will not only be able to increase the economic value of the land, but also can be used as crops of high economic value, and able to provide for the energy needs of the surrounding communities and to the wider region

SIMULASI KENDALI DERAU AKTIF UMPAN MAJU DENGAN MENGGUNAKAN ALGORITMA ADAPTIVE LINE ENHANCER - LEAST MEAN SQUARE (ALE-LMS)

Kendali derau aktif menghilangkan derau berdasarkan prinsip superposisi. Sinyal anti derau dibangkitkan dengan amplitudo yang sama dengan sinyal derau namun berbeda fasa 1800. Kedua sinyal ini dikombinasikan sehingga akan saling menghilangkan. Dengan menerapkan kendali derau aktif maka dapat menunjang performansi sistem agar lebih baik. Metoda yang digunakan untuk membangkitkan sinyal anti derau ini yaitu dengan menerapkan algoritma Adaptive Line Enhancer - Least Mean Square (ALE-LMS) untuk memperbaharui koefisien filter adaptif FIR (Finite Impulse Response). Masalah utama dalam kendali derau aktif dengan algoritma Adaptive Line Enhancer Least Mean Square (ALE-LMS) yaitu pemilihan nilai faktor konvergensi yang tepat untuk mendapatkan peredaman yang optimal, agar pengendali cepat konvergen dan performansi sistem lebih baik. Simulasi diawali dengan pembangkitan sinyal derau, kemudian menerapkan filter adaptif dengan algoritma Adaptive Line Enhacer - Least Mean Square (ALE-LMS) untuk mereduksi derau. Hasil simulasi memperlihatkan bahwa kendali derau aktif dengan algoritma Adaptive Line Enhacer - Least Mean Square (ALE-LMS) mampu meredam sinyal sinusoidal baik pada frekuensi 1000 Hz sebesar 28.32 dB dan meredam sinyal random sebesar 7.99 dB. Kata Kunci : kendali derau aktif, algoritma Adaptive Line Enhacer - Least Mean Square (ALE - LMS) , faktor konvergensi, filter adapti

Skrining Provenan Jarak Pagar Terpilih Di Beberapa Agroekosistem

Pengembangan jarak pagar sebagai bahan bakar nabati (BBN) memerlukan bahan tanam yang unggul. Se-leksi rekuren sederhana terhadap populasi hasil eksplorasi dari beberapa daerah telah menghasilkan tiga po-pulasi unggul, yaitu IP-1A, IP-1M, dan IP-1P yang diprediksi mempunyai potensi produksi 45 ton per ha/ta-hun mulai tahun ke-4. Namun demikian populasi terpilih tersebut apabila dibudidayakan oleh petani secara sederhana, nilai ekonomis hasilnya belum menguntungkan. Penelitian skrining provenan ini dalam rangka mendukung pengembangan varietas unggul jarak pagar berproduktivitas tinggi dan berkadar minyak tinggi. Penelitian ini diawali pada tahun 2007, berlokasi di 3 tempat yaitu Kebun Percobaan (KP) Asembagus, KP Muktiharjo, dan KP Pakuwon. Genotipe yang diskrining sebanyak 20 provenan terdiri atas 17 genotipe yang berasal dari provenan terpilih yaitu HS-49/NTT, SP-16/Sulsel, SP-8/Susel, NTB-2555, NTB-554, NTB-3189, NTB-3052, NTB-575, Puncu/Jatim, PT-3/Lampung, PT-7/Lampung, PT-13/Lampung, PT-14/Lampung, PT-15/Lampung, PT-18/Lampung, PT-26/Banten, PT-33/Lampung, dan 3 populasi terpilih hasil seleksi masa ya-itu IP-1A, IP-1M, IP-1P, yang digunakan sebagai pembanding. Perlakuan disusun dalam rancangan acak ke-lompok dengan ulangan 3 kali. Setiap perlakuan ditanam dalam petak berukuran 10 m x 8 m dengan jarak tanam 2 m x 2 m. Hasil skrining provenan terpilih jarak pagar di Asembagus, Muktiharjo, dan Pakuwon ada-lah tiga provenan yang berpotensi produksi dan berkadar minyak tinggi, yaitu HS-49, NTB-3189, dan PT-7/Lampung. Ketiganya memiliki potensi produksi pada tahun 2009 masing-masing 1.150,70 kg; 1.113,30 kg; 1.064,60 kg/ha/th dan kadar minyak 37,66%; 35,39%; dan 35,84%. The main problem in developing physic nut as a source of biofuel is unavailability of the superior plant mate-rials. Recurent selection of collected physic nut population found three superior provenances i.e., IP-1A, IP-1M, and IP-1P which have been predicted to have production potency of 45 tones/ha/year in fourth year onwards. However, if selected provenances are cultivated with a simple crop management it would not give economically profitable. Therefore, it needs to develop high yield and oil varieties. Screening of selected pro-venances was started 2007 in three Research Stations (RS) Asembagus, Muktiharjo, and Pakuwon, with dif-ferent agroecosystem. The screened genotypes were: HS-49/NTT, SP-16/Sulsel, SP-8/Susel, NTB-2555, NTB-554, NTB-3189, NTB-3052, NTB-575, Puncu/Jatim, PT-3/Lampung, PT-7/Lampung, PT-13/Lampung, PT-14/Lampung, PT-15/Lampung, PT-18/Lampung, PT-26/Banten, PT-33/Lampung, and three of mass se-lected: IP-1A, IP-1M, IP-1P as comparison. This research used randomized block design with three replica-tions. Results showed that three provenances: HS-49, NTB-3189, and PT-7/Lampung have superior potential production and oil content in those three locations. The potential production and oil content of HS-49, NTB-3189, and PT-7/Lampung in 2009 were 1,150.70 kg; 1,113.30 kg; 1,064.60 kg/ha/year; and 37.66%; 35.39%; 35,84% respectively