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The utilization of ice slurry as a pumpable phase-change material has been getting a lot of attention in research and development discourses. This study attempted to investigate the rheological characteristics of ice slurry at different freezing-point depressants through experiments. Ice slurry was formed by mixing water and different freezing-point depressants (monoethylene glycol, ethanol, and sodium chloride) at a 20% initial concentration. Rheology tests were conducted on the transition from laminar to turbulent flows in a circular pipe. The inner dimension of the pipe was 12.7[Formula: see text]mm in diameter, while the ice mass fraction varied in between 0–28% depending on storage time of ice slurry. Experimental results showed sodium chloride ice slurry to have a higher pressure drop and friction factor compared to those of monoethylene glycol and ethanol ice slurry ones at the same initial concentration and ice mass fraction level. In general, ice slurry was discovered to behave as a Newtonian fluid at 10–15% ice mass fractions, as a shear thinning fluid at 15–20% ice mass fractions, and a shear thickening fluid at 20–28% ice mass fractions. Later, experimental data of shear stress were compared to Ostwald–deWaele and Herschel–Bulkley models based on Mellari method. In fact, a modified Herschel–Bulkley model for monoethylene glycol ice slurry showed a close agreement with experimental data with 4.7% mean deviation. In addition, the experimental viscosity data were compared to the Einstein, Jeffrey, Kunitz, Guth, Steimour, Vand, Mooney, Simha, Happel, Ford, Thomas dan Morio–Ototake models. The best fit was only produced with Morio model for values at low ice mass fraction ([Formula: see text]%).

Ice slurry has so many advantages as phase-change slurries due to the high latent heat of its particles. Ice slurry is one of a competitive alternative to conventional secondary refrigeration systems that have been successfully employed in many applications. In this research, ice slurry flow with monoethylene glycol (MEG) at high ice fractions was investigated. The experiment was carried out by measuring shear stress and flow rate as variable to calculate power law index. The experiment was performed in 14 mm, 21 mm, and 24 mm circular tubes, respectively. The Initial concentration of 5 wt%, 7 wt%, and 10 wt% of MEG was investigated. Ice fraction was maintained above 30% in a storage tank. Experimental results of the Darcy friction factor were compared to Poiseuille and Blasius model. The ice slurry flows exhibited a shear-thickening flow (n>1) for all initial concentration in the range 1.07 - 1.58. The Greater initial concentration of MEG tends to give smaller friction compared with another ice slurry flow with smaller initial concentration.

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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 iceslurry 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.

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Realisasi visi, misi, tujuan dan sasaran (corporate statement) sebuah institusi pendidikan bergantung kepada seluruh stakeholder. Guru sebagai salah satu stakeholder, memiliki andil besar dalam merealisasikan corporate statement tersebut. Untuk mengoptimalkan capaian corporate statement institusi, maka rencana beban kerja dan pengukuran kinerja guru harus selaras dengan corporate statement institusi pendidikan. Tujuan dari kegiatan pengabdian kepada masyarakat ini untuk membantu merancang sistem evaluasi kinerja guru di Sekolah Dasar Islam Terpadu Citra Sahabat dalam bentuk pendampingan. Metode yang digunakan mengadopsi kerangka kerja ADDIE (Analyze-Design-Develop-Implementation-Evaluation). Respon Tenaga Kependidikan dan pimpinan sekolah setelah pelaksanaan kegiatan ini sangat positif. Kepala Sekolah mengucapkan terima kasih atas pelaksanaan pendampingan ini dan berharap semoga selanjutnya akan ada program-program lanjutan peningkatan kualitas SDM melalui kegiatan Pengabdian kepada Masyarakat.

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