REVIEW : ALIRAN NEWTON

Abstrak

Praktikum ini dilakukan untuk mempelajari karakteristik aliran Newtonian melalui pengukuran viskositas dan reologi pada beberapa larutan seperti gliserol, sukrosa, NaCl, serta perbandingan air murni dan air mineral dengan menggunakan metode viskometer Ostwald, rheometer rotasional, dan pengukuran viskositas kapiler. Hasil pengamatan menunjukkan bahwa larutan gliserol memiliki viskositas konstan pada berbagai laju geser sehingga menunjukkan sifat Newtonian, larutan sukrosa mengalami peningkatan viskositas seiring bertambahnya konsentrasi namun tetap mempertahankan perilaku Newtonian, larutan NaCl juga menunjukkan karakter Newtonian terutama pada konsentrasi rendah hingga sedang, dan perbandingan air murni dengan air mineral memperlihatkan bahwa keduanya bersifat Newtonian dengan perbedaan viskositas kecil akibat kandungan mineral terlarut. Praktikum ini membuktikan bahwa cairan Newtonian memiliki hubungan linier antara tegangan geser dan laju geser sehingga viskositasnya tidak berubah meskipun gaya geser meningkat.

This practicum was conducted to study the characteristics of Newtonian flow through viscosity and rheology measurements in several solutions such as glycerol, sucrose, NaCl, as well as the comparison of pure water and mineral water using the Ostwald viscometer method, rotational rheometer, and capillary viscosity measurements. The results of the observations showed that the glycerol solution had a constant viscosity at various shear rates so that it showed Newtonian properties, the sucrose solution experienced an increase in viscosity with increasing concentration but still maintained Newtonian behavior, the NaCl solution also showed Newtonian character especially at low to medium concentrations, and the comparison of pure water with mineral water showed that both were Newtonian with small differences in viscosity due to the dissolved mineral content. This practicum proved that Newtonian fluids have a linear relationship between shear stress and shear rate so that their viscosity does not change even though the shear force increases.