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Abstrak :
TES (Thermal Energy Storage) merupakan salah satu teknologi energi yang menjadi banyak perhatian peneliti untuk di kembangan. Ice slurry memiliki banyak kelebihan diantara TES lainnya dimana Ice slurry memiliki densitas penyimpanan energi yang tinggi. Tujuan dari penelitian ini adalah melakukan investigasi aliran ice slurry dengan variasi freezing point depression (glycol, ethanol dan sodium chloride). Fluida dasar disamakan konsentrasinya sebesar 20%. Uji coba reologi dilakukan pada pipa bulat 12.7 mm dengan panjang 1.4 meter yang dimulai dari aliran laminar hingga aliran turbulen. Hasil eksperimen menujukan Fluida ice slurry sangat di pengaruhi oleh waktu operasional mesin bawah. semakin tinggi fraksi es maka semakin tinggi pressure drop yang dihasilkan. Ice slurry sodium chloride memilki pressure drop dan koefisien geek tertinggi dibandingkan dengan ice slurry ethanol dan glycol. Sifat fluida ice slurry akan berubah mengikuti dengan perubahannya fraksi es. Pada fraksi es 10 -  12 %, fluida ice slurry cenderung menyerupai fluida Newtonian. Pada fraksi lebih dari 15% sifat fluida ice slurry menunjukkan fluida non-Newtonian. Model Herschel-Bulkley model pada ice slurry sodium chloride dapat memprediksi shear stress dengan baik, dengan AD dan MD sebesar -0.69% dan 8.79%. persamaan Poiseuille tidak dapat memprediksi dengan baik hampir dari kelurahan data ice slurry pada kondisi laminar. Akan tetapi untuk persamaan Blasius hampir dapat memprediksi sepenuhnya koefisien gesek eksperimen ice slurry. Model viskositas tidak dapat memprediksi dengan baik ketika fraksi es diatas 20%.

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TES (Thermal Energy Storage) is one of the energy technologies that has become a concern for many researchers to develop, recently. Ice slurry has many advantages among other TES where Ice slurry has a high energy storage density. The purpose of this study is to investigate the flow of ice slurry with a variety of freezing point depression (glycol, ethanol and sodium chloride). Base fluid is equated with initial concentration of  20%. The rheology test was carried out on a 12.7 mm circular pipe with a length of 1.4 meters starting from laminar flow to turbulent flow. The experimental results show that ice slurry fluid is greatly influenced by the downtime of operation. the higher the ice fraction, the higher the pressure drop produced. Sodium chloride ice slurry has the highest pressure drop and friction coefficient compared to ethanol and glycol ice slurry. The characteristic of the ice slurry fluid will change with increasing ice mass fraction. at the ice mass fraction of 10-12%, the ice slurry fluid tends to resemble Newtonian fluid. In ice mass fraction of more than 15% the properties of the ice slurry fluid indicate a non-Newtonian fluid. The Herschel-Bulkley model on ice sodium chloride slurry can predict shear stress well, with AD and MD at -0.69% and 8.79%. the Poiseuille equation cannot predict well from the ice slurry data in laminar conditions. However, for the Blasius equation it can almost fully predict the experimental friction coefficient of ice slurry. The viscosity model cannot predict well when the ice fraction is above 20%.

Abstrak :
Ice slurry merupakan salah satu terobosan inovatif terkini dalam penyimpan energi dingin. Pada aspek reologi, permodelan fluida dari aliran ice slurry memiliki karakteristik yang belum banyak di tinjau dan di teliti. Pada studi ini, tujuan dari penelitian ini adalah melakukan studi eksperimen reologi dan visualisasi dari aliran ice slurry pada pipa horizontal. Konsentrasi aditif di variasikan dari 8% - 25% dan fraksi masa es di variasikan dari 4% -29%. Pipa horizontal, sebagai uji reologi, memiliki panjang 1.2 m dengan diameter 25.4 mm. Pengaruh dari kecepatan aliran, pressure drop, temperatur, konsentrasi aditif, dan fraksi massa terhadap reologi ice slurry di ungkap pada penelitian ini. Pengujian reologi ini mencakup aliran laminar hingga transisi. Hasil penelitian reologi mengungkapkan bahwa ice slurry memiliki karakteristik aliran Newtonian dan non-Newtonian tergantung pada fraksi massa yang di hasilkan. Sebagai tambahan, diagram visualisasi aliran dan transport karakteristik dari ice slurry di ajukan pada studi ini. Selanjutnya, Perbandingan data eksperimen dengan berbagai model fluida yang digunakan untuk memprediksi pressure drop ice slurry menunjukkan prediktabilitas yang rendah (yaitu, deviasi rata-rata 30% hingga 86%). Oleh karena itu, model fluida baru dikembangkan dengan menggunakan metode regresi non-linear. Model fluida dari pressure drop ini di definisikan sebagai fungsi dari konsentrasi aditif dan fraksi massa. Model yang dihasilkan berhasil memprediksi data pressure drop dengan deviasi rata-rata 15%. Dengan demikian, penelitian ini dapat memberikan pemahaman mendalam tentang karakteristik reologi dari aliran ice slurry dan berkontribusi pada pengembangan lebih lanjut dari teknologi pendinginan alternatif ini ......Ice slurry is one of the innovative breakthroughs in cold energy storage. In the rheological aspect, ice slurry flow has characteristics that have not been reviewed and thoroughly studied. In this study, the aim of this study was to conduct rheological studies and visualization of the ice slurry flow in a horizontal pipe. The concentration of additives was varied from 8% - 25% and the ice mass fraction was varied from 4% -29%. The horizontal pipe, as a rheological test, has a length of 1.2 m and an inner diameter of 25.4 mm. The effect of flow velocity, pressure drop, temperature, additive concentration, and mass fraction on ice slurry rheology was revealed in this study. The rheological test was conducted from laminar to transition flow. The results of rheological research revealed that ice slurry has Newtonian and non-Newtonian flow characteristics depending on the mass fraction. In addition, visualization diagram and transport characteristics of ice slurry were proposed. A comparison of the experimental data with various existing fluid models used for ice slurry exhibited poor predictability of the pressure drop using these existing models (i.e., a mean deviation of 30%–86%). Therefore, a new fluid model was developed by using a nonlinear regression method, and defining the pressure drop as a function of aditive concentration and ice mass fraction. The resulting model successfully predicted the experimentally obtained pressure data with a mean deviation of 15%. This work thus advances the understanding of the rheological characteristics of ice slurry and will contribute to further development of this alternative cooling technology.

Abstrak :
Ice Slurry merupakan hasil rekayasa sistem pendingin pada evaporator dengan memanfaatkan air laut sebagai media freezing point depressing additive. Teknologi ice slurry sangat berperan penting dalam proses penangkapan ikan di laut lepas, karena kualitas ikan yang di dinginkan oleh ice slurry jauh lebih baik di bandingkan oleh media pendingin lainya. Hal tersebut disebabkan karena ikan didinginkan langsung oleh air laut yang suhu kristal es dapat mencapai dan seluruh badan ikan dapat terselubungi penuh dengan es. Penggunan propane sebagai media refrigerant dapat meningkatkan waktu terbentuknya ice slurry dan propane merupakan refrigerant yang ramah lingkungan. Tujuan dari penelitian ini adalah untuk merancang prototipe ice slurry dan menganalisis perfroma sistem dengan membandingkan kualitas es antara penggunaan refrigerant R-22 dan propane. Parameter kualitas es pada penelitian ini adalah banyaknya es yang terbentuk terhadap lamanya waktu sistem bekerja dan ketahanan scraper dalam melakukan pengikisan es didalam evaporator. Sehingga semakin cepat ice slurry terbentuk dan scraper dapat terus beroperasi, maka semakin baik sistem rancangan. Variasi antara putaran scraper dan pompa merupakan variabel penentu kualitas es. Hasil dari penelitian ini menunjukan bahwa pembentukan ice slurry dengan refrigerant propane lebih baik dibandingkan R-22 yang ditinjau bedasarkan waktu penurunan suhu air laut, kestabilan tekanan kerja dan perfoma scraper. ...... Ice Slurry is engineered cooling system on the evaporator with the use of seawater as a medium freezing point depressing additive. Ice slurry technology plays an important role in the process of fishing on the high seas, because the quality of the fish is cooled by ice slurry is much better compared to other cooling media. This is because the fish is cooled directly by seawater temperature ice crystals can reach -10 ℃ and whole body fish can be enveloped filled with ice. The use of propane as a refrigerant media can also increase the time the formation of ice slurry and propane is an environmentally friendly refrigerant. The Purpose of this research is to create a prototype of ice slurry and analyze perfrom of system by comparing the quality of the ice between the use of refrigerant R-22 and propane. Ice quality parameters in this study is the number of ice that forms on the length of time the system works and ablitity of scraper scorns of ice in evaporator. So the faster the ice slurry is formed and scraper can keep operated, the better the system design. Variations between rounds scraper and pump are variables determine the quality of the ice. The results of this study indicate that the formation of ice slurry with refrigerant propane better than R-22, which are reviewed by temperature of sea water, the stability of working pressure and performence of scraper.

Abstrak :
Ice slurry technology is highly favored to maintain the freshness of fish, as the cooling capacity of ice slurry is higher than that of flaked ice, tubular ice, plate ice, and block ice. One important part of an ice-slurry system is the ice generator. A mechanical scraper is the easiest type of ice-slurry generator to fabricate, because mechanical scrapers use only one type of material, such as stainless steel. The purpose of this research was to develop a prototype ice-slurry generator and analyze its performance. To enable comparison of their performance, both the R-22 and R-290 refrigerants were used as the working fluids in the refrigeration system. The study observed the time necessary to form ice and the scraper’s ability to scrape the ice on the inner surface of the evaporator. The best system included faster ice-slurry generation and a durable generator that did not freeze up. Four combinations of scraper RPM and pump RPM varied speeds from low to high. The results showed that using R-290 refrigerant and lower RPM speeds for both the scraper and the pump generated ice slurry in a shorter time.