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Abstrak :
Salah satu pengembangan metode terbaru terkait alat uji siklus termal PCM adalah dengan menggunakan modul termoelektrik sebagai elemen pemanas dan pendingin. Kekurangan dari metode sebelumnya yaitu perubahan polaritas termoelektrik yang berdasarkan waktu, volume sampel yang besar dalam cartridge, kesulitan dalam mengeluarkan sampel PCM, dan membersihkan cartridge setelah digunakan. Penelitian ini bertujuan untuk mengembangkan metode pengujian siklus berbasis termoelekrik dengan perubahan polaritasnya berdasarkan temperatur sampel PCM, membuat cartridge dengan volume yang lebih sedikit, dan juga dapat dibongkar-pasang. Metode yang baru ini diuji dengan menggunakan sampel PCM berupa beeswax dan RT44HC. Hasil dari penelitian menunjukkan metode terbaru ini dapat mencapai titik leleh dan titik beku dari sampel secara bergantian dan otomatis. Pengujian karakteristik termal menunjukkan beeswax dan RT44HC yang dapat mempertahankan temperatur leleh dan bekunya setelah pengujian 1000 siklus. ...... One of the most recent developments of PCM thermal cycling test method is by applying thermoelectric module as a heating and cooling element. The disadvantages of previous method were the alteration in thermoelectric polarity was based on time, large volume of sample in a cartridge, difficulty in taking out PCM samples, and cleaning the cartridge after use. This research aims to develop a method of cycling test using thermoelectric polarity was changed according to PCMs sample temperature, to build cartridge with less volume, and make a cartridge that can be disassembled. The new modified apparatus was operated over beeswax and RT44HC as PCM samples. The results of this research showed that the modified test apparatus had alternately and automatically reached melting and cooling temperature. From thermal characterization, beeswax and RT44HC is able to maintain its melting and freezing temperature after 1000 cycles, while its heat of fusion had undergone degradation.

Abstrak :
Penelitian ini memiliki tujuan untuk menghasilkan Phase Change Material (PCM) organik berbasis natural wax dan aplikasinya pada manajemen termal bangunan. Selain itu untuk mengetahui pengaruh nanopartikel, yaitu grafena dan MAXene dalam komposit PCM yang dihasilkan melalui metode impregnasi basah. Natural wax yang digunakan adalah soy wax, paraffin wax dan palm wax. Nanopartikel grafena dan MAXene (Ti3AlC2) ditambahkan sebesar 0,1 – 1 wt.% ke dalam PCM untuk meningkatkan konduktivitas termal dan stabilitas termal komposit nano-PCM. Uji siklus termal (500 – 5000 siklus) dan aplikasi manajemen termal hanya dilakukan pada PCM soy wax murni yang memiliki performa terbaik berbanding natural wax yang lain. Alat uji siklus termal berbasis termoelektrik, penambahan 4 modul, desain sederhana, sistem kerja otomatis dan simultan juga dirancang untuk meningkatkan efisiensi waktu pengujian. Nano-PCM dikarakterisasi menggunakan Scanning Electron Microscope- Energy Dispersive X – Ray Spectroscopy (SEM-EDS), Differential Scanning Calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR) dan konduktivitas termal. Hasil konduktivitas termal komposit nano-PCM soy wax-grafena dan soy wax-MAXene masing-masing adalah 0,88 W/mK dan 0,85 W/mK pada 1 wt%. Konduktivitas termal pure soy wax (0,18 W/mK) meningkat sebesar 6,01% untuk soy wax+grafena dan 5,71% untuk soy wax+MAXene. Hasil DSC menunjukkan soy wax dengan penambahan masing-masing grafena dan MXene 0,1 wt% memiliki kenaikan titik leleh sebesar 15% dan 16% serta penurunan titik beku sebesar 14% dan 13%. Hasil uji siklus termal menggunakan pure soy wax dengan alat thermal cycle yang didesign menghasilkan 13 siklus dalam waktu sangat efisien hanya 1 jam pengujian dan setelah 5000 siklus mengalami penurunan ΔH sebesar 60%. Uji performa PCM pada prototipe model dinding bangunan ukuran 101 x 50 x 80 cm untuk skala 1:5 mengunakan polywood dilakukan dengan mengenkapsulasi pure soy wax dalam kantong aluminium foil sebesar 250 g dan ketebalan 1 cm dan pengujian dilakukan selama 24 jam. Aplikasi manajemen termal menunjukkan pure soy wax pack menghasilkan penyerapan panas sebesar 10% dari 41oC menjadi 37oC dibandingkan dengan prototipe bangunan tanpa lapisan soy wax pack. Material maju PCM berbasis pure soy wax memiliki potensi sebagai material manajemen termal pada aplikasi bangunan dan mengoptimalkan penggunaan energi untuk sistem pendinginan pada bangunan. ......This study aims to produce an organic Phase Change Material (PCM) based on natural wax and its application to the thermal management of buildings. In addition, graphene and MAXene in PCM composites were produced through the wet impregnation method to determine the effect of nanoparticles. Natural wax used is soy wax, paraffin wax, and palm wax. Graphene and MAXene (Ti3AlC2) nanoparticles were added at 0.1-1 wt.% to the PCM to increase the thermal conductivity and thermal stability of the nano-PCM composite. Thermal cycle tests (500-5000 cycles) and thermal management applications are only carried out on pure PCM soy wax which has the best performance compared to other natural waxes. Thermoelectric-based thermal cycle test equipment, the addition of 4 modules, a simple design, and an automatic and simultaneous working system are also designed to increase the efficiency of testing time. Nano-PCM was characterized using Scanning Electron Microscope- Energy Dispersive X-Ray Spectroscopy (SEM-EDS), Differential Scanning Calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), and thermal conductivity. The thermal conductivity of soy wax-graphene and soy wax-MAXene nano-PCM composites were 0.88 W/mK and 0.85 W/mK at 1 wt%, respectively. The thermal conductivity of pure soy wax (0.18 W/mK) increased by 6.01% for soy wax+graphene and 5.71% for soy wax+MAXene. DSC results showed that soy wax with the addition of graphene and MXene 0.1 wt%, respectively, had a melting point increase of 15% and 16% and a freezing point depression of 14% and 13%, respectively. The results of the thermal cycle test using pure soy wax with a thermal cycle tool designed to produce 13 cycles in a very efficient time of only 1 hour of testing and after 5000 cycles the H decreased by 60%. PCM performance test on a prototype building wall model measuring 101 x 50 x 80 cm for a scale of 1:5 using polywood was carried out by encapsulating pure soy wax in an aluminum foil bag of 250 g and a thickness of 1 cm and the test was carried out for 24 hours. Thermal management application shows that pure soy wax pack produces 10% heat absorption from 41oC to 37oC compared to building prototype without soy wax pack coating. Advanced PCM materials based on pure soy wax have potential as thermal management materials in building applications and optimize energy use for cooling systems in buildings.

Abstrak :
[Salah satu tantangan dalam meningkatkan standar kesehatan di Indonesia adalah masih tingginya angka kelahiran bayi prematur. Upaya penyelamatan bayi yang lahir prematur terhambat oleh beberapa faktor terutama faktor ekonomi yang disebabkan mahalnya biaya perawatan di ruang NICU rumah sakit. Selain itu, distribusi listrik yang belum merata menyebabkan sedikitnya rumah sakit yang menyediakan fasilitas inkubator terutama pada wilayah terpencil di Indonesia. Penggunaan Phase Change Materials dari kelompok organik sebagai elemen pemanas inkubator portable non-elektrik agar aman bagi pernafasan bayi dan mudah pendistribusiannya menjadi salah satu alternatif upaya penyelamatan bayi prematur yang lahir terutama diwilayah yang belum dialiri listrik nasional. Eksperimen ini bertujuan mendapatkan masa PCM yang paling efisien sesuai Standar Nasional Indonesia untuk mendapatkan rentang waktu dan temperatur paling ideal bagi bayi prematur. Juga pengurangan masa PCM akan meringankan bobot inkubator secara total serta mengurangi biaya. Eksperimen dilakukan menggunakan prototype Inkubator Grashof seri-F yang memanfaatkan fenomena konveksi natural dalam proses pemanasan ruang inkubator. Temperatur diukur menggunakan termokopel tipe K yang dihubungkan pada Modul NI9211. Grafik pengukuran digambarkan oleh perangkat lunak Labview 8.5 yang diinstal pada Personal Computer Unit. Hasil eksperimen menunjukkan masa PCM jenis Beeswax sebesar 3kg adalah yang paling efisien dalam penggunaan energi. Aplikasi fin juga membantu mempersingkat waktu tunggu sebelum penggunaan inkubator dan distribusi panas yang lebih merata dalam ruang inkubator. ......One of the challenges in improving health standards in Indonesia is a high number of neonatal birth. Government efforts to save neonatals hampered by several factors especially economic factors caused by high cost of neonatals care in NICU room at the hospital. Moreover, the uneven of electricity distribution cause least hospitals providing incubator facilities, especially for remote areas in Indonesia. The use of Phase Change Materials from the organic group as a heating element for portable non-electric incubator to be safe for the baby's breathing and easy distribution into an alternative rescue efforts, especially premature babies born in the region that has not been electrified nationwide. Experiments aimed at finding the most efficient mass of PCM based on Indonesian National Standard to get the ideal time and temperature range for premature babies. PCM mass reduction also will lighten the weight of the incubator in total as well as reduce costs. Experiments conducted using prototype Incubator Grashof-F series which utilizes natural convection phenomena in the process of incubator space heating. Temperatures were measured using a K-type thermocouple connected to the module NI9211. Measurement chart illustrated by Labview 8.5 software installed on the Personal Computer Unit. The experimental results indicate the mass of 3kg PCM types Beeswax is the most efficient in energy use. Applications fin also help shorten the waiting time before the use of incubators and more even heat distribution within the incubator.;One of the challenges in improving health standards in Indonesia is a high number of neonatal birth. Government efforts to save neonatals hampered by several factors especially economic factors caused by high cost of neonatals care in NICU room at the hospital. Moreover, the uneven of electricity distribution cause least hospitals providing incubator facilities, especially for remote areas in Indonesia. The use of Phase Change Materials from the organic group as a heating element for portable non-electric incubator to be safe for the baby's breathing and easy distribution into an alternative rescue efforts, especially premature babies born in the region that has not been electrified nationwide. Experiments aimed at finding the most efficient mass of PCM based on Indonesian National Standard to get the ideal time and temperature range for premature babies. PCM mass reduction also will lighten the weight of the incubator in total as well as reduce costs. Experiments conducted using prototype Incubator Grashof-F series which utilizes natural convection phenomena in the process of incubator space heating. Temperatures were measured using a K-type thermocouple connected to the module NI9211. Measurement chart illustrated by Labview 8.5 software installed on the Personal Computer Unit. The experimental results indicate the mass of 3kg PCM types Beeswax is the most efficient in energy use. Applications fin also help shorten the waiting time before the use of incubators and more even heat distribution within the incubator., One of the challenges in improving health standards in Indonesia is a high number of neonatal birth. Government efforts to save neonatals hampered by several factors especially economic factors caused by high cost of neonatals care in NICU room at the hospital. Moreover, the uneven of electricity distribution cause least hospitals providing incubator facilities, especially for remote areas in Indonesia. The use of Phase Change Materials from the organic group as a heating element for portable non-electric incubator to be safe for the baby's breathing and easy distribution into an alternative rescue efforts, especially premature babies born in the region that has not been electrified nationwide. Experiments aimed at finding the most efficient mass of PCM based on Indonesian National Standard to get the ideal time and temperature range for premature babies. PCM mass reduction also will lighten the weight of the incubator in total as well as reduce costs. Experiments conducted using prototype Incubator Grashof-F series which utilizes natural convection phenomena in the process of incubator space heating. Temperatures were measured using a K-type thermocouple connected to the module NI9211. Measurement chart illustrated by Labview 8.5 software installed on the Personal Computer Unit. The experimental results indicate the mass of 3kg PCM types Beeswax is the most efficient in energy use. Applications fin also help shorten the waiting time before the use of incubators and more even heat distribution within the incubator.]

Abstrak :
Peningkatan kadar CO2 pada setiap tahun dan terbatasnya sumber daya fosil untuk masa depan mendorong produsen mobil untuk mengembangkan kendaraan berbahan bakar listrik sebagai kendaraan masa depan. Pengembagan terus dilakukan di berbagai sektor, salah satunya pada sistem penyimpanan energi yaitu baterai. Peningkatan kapasitas baterai dan mempertahankan kapasitasnya menjadi tujuan utama dalam pengembangan sektor ini untuk mendorong mobil listrik menjadi mobil masa depan. Pada penelitian ini, pemanfaatan heat pipe dan PCM sebagai media pendingin pasif pada baterai membuat temperature baterai dapat dijaga, sehingga baterai tidak mengalami kelebihan temperatur yang menyebabkan degradasi kapasitas. Penelitian ini bertujuan untuk melihat efektivitas heat pipe dalam menjaga temperatur baterai dan untuk mendapatkan jenis PCM terbaik beeswax dan RT 44 HC sebagai sistem pendingin baterai. Mengingat temperatur baterai harus dijaga pada rentang 25-55oC, pemanfaatan heat pipe berbentuk L pada baterai dapat mempengaruhi temperature baterai. Penurunan temperatur dapat mencapai 26.62oC pada 60 watt energi panas dari baterai bila dibandingkan jika tidak menggunakan apapun. Ketika PCM dikombinasikan dengan heat pipe menunjukan performa yang jauh lebih baik. Penurunan temperatur baterai dapat mencapai 31.93oC ketika beeswax digabungkan dengan heat pipe sebagai media pendigin baterai. Sedangkan ketika RT 44 HC digabungkan dengan heat pipe, penurunan temperatur dapat mencapai 33.42oC. Oleh karena itu PCM terbaik adalah RT 44 HC yang memiliki temperature leleh pada temperatur kerja baterai yang direkomendasikan, sehingga kalor latent dari PCM dapat dimanfaatkan. Kombinasi antara heat pipe dan PCM dapat menurunkan temperatur baterai lebih banyak karena heat pipe melepakan energi panas ke udara, dan PCM menyerapnya.

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The Enhancement of CO2 level for each year and limited fossil energy resources for future lead to the car manufacturers starting to develop electric vehicle as the future vehicle. Developments are being done in many sectors, one of them in the energy supply. Increasing and maintaining battery capacity becomes one of the concern to create a sustainable electric vehicle. In this experiment, the utilization of heat pipe and PCM as passive cooling system on battery simulator have been conducted. The research objectives are to determine their effectiveness in maintaining battery temperature and to get the best PCM type beeswax and RT 44 HC for battery cooling system, considering the temperature should be maintained at 25 55 oC. The utilization of wick L shaped flat heat pipe as a passive battery cooling system influenced the temperature of battery, the battery temperature decreased until 26.62 oC on 60 watt of heat energy when it was compared with the battery did not use heat pipe and PCM. When PCM was combined with heat pipe also showed better performance. A maximum temperature decreased until 31.93oC when beeswax was added to the heat pipe. When RT 44 HC was combined to the heat pipe, the battery temperature decreased until 33.42oC. Therefore, the best PCM type which has melting temperature on recommended battery temperature. thus the PCM can use its latent heat to store more heat energy from the battery. Combination between heat pipe and PCM can reduced more battery temperature because heat pipe released heat energy and PCM absorbed it.

Abstrak :
This short book provides an update on various methods for incorporating phase changing materials (PCMs) into building structures. It discusses previous research into optimizing the integration of PCMs into surrounding walls (gypsum board and interior plaster products), trombe walls, ceramic floor tiles, concrete elements (walls and pavements), windows, concrete and brick masonry, underfloor heating, ceilings, thermal insulation and furniture an indoor appliances. Based on the phase change state, PCMs fall into three groups: solid–solid PCMs, solid–liquid PCMs and liquid–gas PCMs. Of these the solid–liquid PCMs, which include organic PCMs, inorganic PCMs and eutectics, are suitable for thermal energy storage. The process of selecting an appropriate PCM is extremely complex, but crucial for thermal energy storage. The potential PCM should have a suitable melting temperature, and the desirable heat of fusion and thermal conductivity specified by the practical application. Thus, the methods of measuring the thermal properties of PCMs are key. With suitable PCMs and the correct incorporation method, latent heat thermal energy storage (LHTES) can be economically efficient for heating and cooling buildings. However, several problems need to be tackled before LHTES can reliably and practically be applied.

Abstrak :
Thermal Energy Storage (TES) dengan material Phase Change Materials (PCM) dapat dijadikan salah satu solusi untuk mengurangi konsumsi energi listrik pada sistem air conditioner (AC). RT 22 HC merupakan salah satu PCM komersial yang memiliki kalor laten yang tinggi. Tujuan dari penelitian ini adalah untuk mengetahui sifat ? sifat termal dari PCM RT 22 HC dengan penambahan nanopartikel Graphene (0,05, 0,10, 0,15, 0,20, 0,25, dan 0,30 wt%) dan memastikan kestabilan termal pada PCM/nano PCM dengan melakukan pengujian siklus termal. Kalor laten, titik leleh, titik beku, dan kalor jenis dari nano PCM RT 22 HC/Graphene dianalisis dengan Differential Scanning Calorimetry (DSC), sedangkan konduktivitas termalnya diukur dengan alat KD2 Pro Thermal Analyzer. Viskositas fluidanya juga diukur dengan DV-E Brookfield Viscometer. Pengujian siklus termal menggunakan termoelektrik sebagai elemen pemanas dan pendinginnya. Penambahan nanopartikel Graphene akan meningkatkan konduktivitas termal dan viskositas fluidanya, akan tetapi menurunkan kalor laten dan kalor jenisnya. Hasil pengujian 1000 siklus termal pada PCM/nano PCM menunjukan kestabilan termal yang baik. Berdasarkan hasil, dapat disimpulkan bahwa PCM RT 22 HC dan nano PCM RT 22 HC/Graphene berpotensi untuk diaplikasikan pada sistem AC. ...... Thermal Energy Storage (TES) with Phase Change Materials (PCM) may be one solution to reduce the consumption of electrical energy in air conditioner (AC) system. RT 22 HC is one of commercial PCM with high latent heat. The objective of this study was to determine the properties of PCM RT 22 HC with addition of Graphene nanoparticles (0.05, 0.10, 0.15, 0.20, 0.25 and 0.30 wt%) and ensure the thermal stability of PCM/nano PCM by performing thermal cycling test. The latent heat, melting point, freezing point and specific heat capacity were analyzed by Differential Scanning Calorimetry (DSC) while thermal conductivity was measured using KD2 Pro Thermal Properties Analyzer device. The viscosity was also measured by DV-E Brookfield Viscometer. Thermal cycling test utilize thermoelectric as heating and cooling element. The existing of Graphene nanoparticles enhanced thermal conductivity and viscosity of PCM, however it would reduce latent heat and specific heat capacity. The test results of 1000 thermal cycle on PCM/nano PCM showed good thermal stability. Therefore, based on these results, it could be concluded that PCM RT 22 HC and nano PCM RT 22 HC/Graphene have potential to be applied in AC system.