Hasil Pencarian  ::  Simpan CSV :: Kembali

"This book constitutes the refereed proceedings of the 10th International Conference on Formal Modeling and Analysis of Timed Systems, FORMATS 2012, held in London, UK in September 2012. The 16 revised full papers presented together with 2 invited talks were carefully reviewed and selected from 34 submissions. The book covers topics of foundations and semantics, methods and tools, techniques, algorithms, hybrid automata, appilcations, real-time software and hardware circuits."

"Indonesia merupakan negara beriklim trpois dengan temperatur udara berkisar 28°C-35°Cdengan kelembaban Relative Humidity 70%-90%. Sedangkan kondisi nyaman udara pada suatu ruangan yaitu pada temperature 22°C-25°C dengan kelembapan relative humidity 40%-60%. Oleh karena itu pengkondisian udara merpakan sebuah solusi atas permasalahan tersebut. Hampir semua pengkondisian udara di Indonesia dilakukan dengan cooling dan dehumidification. Pada perkembangan beberapa akhir tahun ini, biaya operasional bangunan telah habis hingga 60% digunakan untuk pengkondisian udara. Aplkasi Heat pipe dalam pengkondisian udara telah banyak diterapkan. Heat pipe merupakan sebuah alat heat exchanger dengan kemampuan transfer panas yang sangat baik. Heat pipe dapat berfungsi sebagai precooler dan reheater serta berperan dalam menurunkan relative humidity.

---

Indonesia have a tropic climate with 28°C-35°C in temperature and 70%-90% in Relative Humidity. Comfortable condition of air in building is about 22°C-25°C and relative humidity 40%-60%. So, air conditioning which in Indonesia using cooling and dehumidification system is a solution. But the cost of air conditioning is very expensive and almost spend 60% of operational cost. So, heat pipe application in heat exchanger for air conditioning is often used. Heat pipe have a good ability in heat exchanger. It's function for precooling, reheating and also dehumidification in air conditioning."

"ABSTRAKRelative Humidity adalah salah satu aspek penting yang harus dikontrol pada system pengkondisian udara.Namun, Penggunaan energy reheat untuk mengontrol Humidity pada system pengkondisian udara secara konvensional memerlukan energy tambahan yang tidak sedikit . Untuk meningkatkan efisiensi, dilakukan penelitian heat pipe pada aplikasi pengkondisian udara yang dilakukan di Laboratorium Pendingin, Departmen Teknik Mesin FTUI. Pada studi ini beberapa aspek yang dikaji adalah besar performance heat pipe dalam meningkatkan Penurunan Humidity, Besar energy untuk Reheat dari Heat pipe, Penurunan Humidity ratio, dan total penghematan energy pengkondisian udara dengan memvariasikan mass flow rate udara dan orientasi heat pipe. Dari studi yang telah dilakukan, Heat pipe dapat berperan meningkatkan pernurunan kelembaban system pengkondisian udara secara konvensional dan Mengurangi energy untuk reheating. Penggunaan Heat pipe dapat meningkatkan penurunan humidity hingga maksimal 6.405% dan minimal 3.12% pada keseluruhan variable pengujian. Penggunaan Heat pipe dapat menghemat energy untuk reheating hingga maksimum 18.2% dan minimum 8.77% pada keseluruhan variable uji. Mass flow rate udara mempengaruhi performance heat pipe dalam precooling dan reheating. Peningkatan mass flow rate meningkatkan preheating dan precooling heat pipe namun disisi lain daya untuk kipas juga meningkat.Performance heat pipe dengan orientasi heat pipe vertical dan evaporator dibawah lebih baik bila dibandingkan dengan orientasi heat pipe horizontal hal ini disebabkan karena laju aliran working fluida dari condenser heat pipe ke evaporator meningkat karena pengaruh gravitasi.

---

ABSTRACTRelative Humidity is important aspect that must be controlled in Air Conditioning.however. air conditioning system, must have additional energy reheat to control Humidity in the air conditioning.To improve efficiency, conducted research on the application of heat pipe in air conditioning is performed at the Laboratory, Department of Mechanical Engineering University of Indonesia.In the present study examined several aspect of the performance heat pipe to increasing humidification, energy to reheat form heat pipe and total air conditioning saving energy by varying the air mass flow rate and heat pipe orientations. The studies have been done, heat pipe can be enchanment humdification in convetional air conditioning and reduce energy for reheating.Using heat pipe in conventional air conditioning system can improve humidification minimum at 3.12 % and maximum at 6.405% in the overall test variable. the use of heat pipe can save energy for reheating up to maximum 18.2% and minimum 8.77% on the overall test variable. Air mass flow rate affect the performance of heat pipe in the precooling and reheating. Increase in air mass flow rate increase precooling and reheating heat pipe but on the other hand power of fan also increase. Performance of heat pipe with vertical orientation where evaporator of heat pipe in bottom is more better when compared to the horizontal orientation. this is because the flow rate of working fluid from the condenser of heat pipe to evaporator of heat pipe is increasing by gravity."

"ABSTRACTPemanfaatan limbah panas adalah salah satu cara untuk mengurangi penggunaan bahan bakar fosil, salah satunya adalah dengan menggunakan generator termoelektrik untuk mengubah limbah panas menjadi energi listrik. Thermoelectric Generator TEGs adalah modul yang dapat mengubah panas menjadi daya listrik secara langsung, menggunakan efek Seebeck dan efek Peltier sebagai prinsip kerjanya, sehingga dapat meningkatkan efisiensi konsumsi energi dengan memanfaatkan panas limbah dari instrumen yang menghasilkan limbah panas. Fokus dari penelitian ini adalah untuk menemukan tegangan output modul TEG dengan memanfaatkan perbedaan suhu pada sisi dingin dan sisi panas TEG. Sisi panas dari modul akan diberi panas dari pemanas sebagai simulasi panas dari air panas, dan digunakan heat pipe untuk menghilangkan panas pada sisi dingin TEG. Tegangan output yang dihasilkan dengan menggunakan 4 modul TEG yang disusun secara Seri Termal - Seri Listrik dan menggunakan 2 heat pipe adalah 2,1 Volt.

---

ABSTRACTWaste heat recovery is one way to reduce the use of fossil fuels, one of them is by using thermoelectric generator to convert waste heat into Thermoelectric Generator TEGs is a module that can convert heat into electrical power directly, using Seebeck effect and Peltier effect as its working principle, so it can increase efficiency of energy consumption by utilizing waste heat from an instrument that generate waste heat. The focus of this research is to find the output voltage of TEG by utilizing the temperature difference on the cold side and the heat side of the TEGs. The heat side of the module will be given heat from the heater as a simulation of the heat from hot water, and on the cold side heat pipes will be used to remove the heat on the cold side of TEGs. The result, output voltage that generated by using 4 module TEGs that arranged to thermal series electrical series and using 2 heat pipes is 2,1 Volt."

"Contents :- Thermal residual stress relaxation and distortion in surface enhanced gasturbine engine components - Development of machining procedures to minimize distortion during manufacture - Control of distortion by quenching in fluidised beds - Optimization of single part quenching in nozzle fields - Hardening of steel parts using wave technology - Continuous vacuum carburizing furnace with 20 bar high-pressure gas quenching - New carburizing techniques using fluidized bed furnaces - The experience at dana corporation, spicer transmission division - Progress in the application of high pressure gas quenching - Atmosphere control system to achieve consistent carburizing in batch furnaces - MSSR (Military Specification and Standards Reform) how does it affect your operation? - Advanced radiant tubes: payback calculations of furnace retrofits - Cost justification in the selection of heat resistant alloys - Principles of airlessTM solvent degreasing - Principles and use of dissociated ammonia - Principles and use of endothermic atmosphere - Supervisory control systems for vacuum furnaces - Supervisory and process control to enhance batch vacuum processing - Brite heat treating in a fluidized bed - Heat treating in fluidized bed furnaces in cutting tool manufacturing treaters - Gas-fired ion nitriding furnace lowers utility costs for commercial heat treaters - Techniques for distortion control during vacuum oil quenching of high strength steel aircraft components...."

"This volume presents the refereed proceedings of the 7th International ICST Conference on Security and Privacy in Communication Networks, SecureComm 2011, held in London, UK, in September 2011. The 35 revised papers included in the volume were carefully reviewed and selected from numerous submissions. Topics covered include network intrusion detection, anonymity and privacy, wireless security, system security, DNS and routing security, and key management."

"Peningkatan flux kalor yang dihasilkan oleh peralatan elektronik khususnya komponen dari CPU komputer harus selalu diiringi dengan pendinginan yang baik. Flux kalor pada komponen CPU komputer harus dapat direduksi secara maksimal agar bisa mencapai kemampuan operasi yang optimal dengan tingkat reliability yang tinggi. Penggunaan straight heat pipe dalam pendinginan tersebut menjadi salah satu solusi alternatif guna menyerap kalor yang dihasilkan.Penelitian ini memperlihatkan pengaruh number of screen mesh wick terhadap kinerja straight heat pipe yang menggunakan pipa tembaga. Screen mesh wick yang digunakan adalah screen 100, 200, 250, dan 300 mesh. Pengujian dilakukan menggunakan pipa tembaga dengan panjang 200 mm dan berdiameter 6 mm, 8 mm, dan 10 mm dengan fluida kerja air. Hambatan termal diukur melalui wick dengan variasi input daya yang diberikan oleh pemanas elektrik dengan 6 titik pengukuran temperatur sepanjang heat pipe menggunakan termokopel.Didapatkan bahwa semakin besar number of screen mesh wick yang digunakan, dapat meningkatkan kinerja heat pipe dimana temperatur di bagian evaporator dapat direduksi paling besar hingga 20,63% untuk screen 300 mesh dibanding screen 100 mesh. Hal ini dikarenakan hambatan termal pada straight heat pipe semakin kecil dengan meningkatnya number of screen mesh wick yang digunakan. Semakin besar number of screen mesh wick, straight heat pipe yang diuji menunjukkan nilai Heat Transfer Coefficient yang semakin besar pula.

---

Increased of heat flux generated by electronic equipment in particular componentsof a computer CPU should always be accompanied with a good cooling. Heat fluxon the computer CPU components must be reduced to maximum in order toachieve optimal operating capability with a high level of reliability. The use ofstraight heat pipes in the cooling of it become one of alternative solution in orderto absorb the heat generated.This experiment shows the influence of number of screen mesh wick on performance of straight heat pipe that use copper pipe. Screen mesh wick that used is screen 100, 200, 250, and 300 mesh. The experiment use copper pipe with a length of 200 mm and diameter 6 mm, 8 mm, and 10 mm with working fluid water. Thermal resistant is measured through the wick with a variety of input power supplied by electric heaters with 6 points along the heat pipe temperature measurement using thermocouples.It was found that the greater the number of screen mesh wick which is used, can improve the performance of heat pipes where the temperature at the evaporator can be reduced to the most up to 20.63% for the screen 300 mesh compare to the screen 100 mesh. This is because the thermal resistance on the straight heat pipe decreased with increasing number of screen mesh wick which is used. The greater the number of screen mesh wick, straight heat pipes that are tested show the number of Heat Transfer Coefficient is greater as well."