Sains Malaysiana 40(5)(2011): 509–513

Hubungan Kelikatan Minyak Enjin Terhadap Usia Guna Serta Suhu

(Relationship Between Engine Oil Viscosity with Age and Temperature)

Nordin Jamaludin¹, Othman Inayatullah^2,*, Mohd. Jailani Mohd. Nor¹ & Fauziah Mat³

¹Fakulti Kejuruteraan dan Alam Bina, Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor, D.E., Malaysia

²Pusat Pengajian Kejuruteraan Pembuatan, Universiti Malaysia Perlis

Kampus Alam Pauh, 02600 Arau, Perlis, Malaysia

³Pusat Pengajian Kejuruteraan Mekatronik, Universiti Malaysia Perlis

Kampus Alam Pauh, 02600 Pauh, Perlis, Malaysia

Diserahkan: 5 Januari 2010 / Diterima: 20 September 2010

ABSTRAK

Kelikatan minyak enjin bergred tunggal mengalami perubahan apabila berlakunya perubahan pada suhu dan tekanan. Namun begitu, secara realiti kelikatan minyak enjin juga mengalami perubahan terhadap usia guna. Oleh itu, kajian ini memperkenalkan satu hubungan kelikatan minyak enjin terhadap perubahan suhu serta usia guna. Hubungan ini berasaskan kepada persamaan matematik empirik yang melibatkan teori pelincir Newtonan dan bukan Newtonan. Hubungan yang baru ini dikenali sebagai model kelikatan matematik (ηmath). Dalam model ini, kelikatan minyak enjin dipengaruh oleh dua faktor iaitu faktor suhu (ks) dan faktor masa (km). Nilai kedua-dua faktor ini bergantung kepada formula bahan tambah minyak enjin tersebut. Analisis reologi meter likat telah digunakan untuk mendapatkan nilai kedua-dua faktor ini. Hasil kajian menunjukkan kelikatan minyak enjin mengalami penurunan apabila usia guna meningkat. Ini dibuktikan melalui model kelikatan matematik (ηmath) dan juga analisis reologi meter likat.

Kata kunci: Faktor masa; faktor suhu; kelikatan; minyak enjin; model kelikatan matematik

ABSTRACT

Single grade engine oil viscosity experience changes influenced by temperature and pressure. In reality however, the viscosity of the engine oil is also affected by age. A relationship between oil’s viscosity with temperature and age is proposed in this paper. This relationship is based on an empirical mathematical equation which involves Newtonian and non-Newtonian lubricant theory. Based on the model proposed, the engine oil viscosity was influenced by two factors namely temperature (ks) and time (km). Both of there factors depends on the engine oil additive formula. As such, by applying rheology viscometer analysis, the value of these factors can be determined. This research showed that the engine oil viscosity was inversely proportional with the use age, established via mathematical viscosity model (ηmath) and also rheology viscometer analysis.

Keyword: Engine oil; mathematical viscosity model; temperature; time

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*Pengarang untuk surat-menyurat; email: othatiah@gmail.com