[ABSTRAK
Aliran turbulen dari larutan polimer PEG 4000 untuk permukaan pipastainless steel telah diteliti. Eksperimen ini menggunakan pipa stainless steelberdiameter luar 5 mm dan diameter dalam pipa 3 mm. Nilai dari kekasarantersebut telah diukur tersebut dengan nilai kekasaran (k) 1.12 μm. Pipatersebut diuji dengan konsentrasi polimer polyethylene glycol (PEG) 4000200, 400 dan 600 ppm. Hasil menunjukkan bahwa karakteristik alirandipengaruhi oleh penambahan konsentrasi polimer. Pada aliran turbulen tanpaadditive kenaikan koefisien gesek terjadi akibat dari kondisi kekasarandinding. Penambahan additive ke dalam air terlihat efektif pada permukaanpipa stainless steel. Penambahan 200 ppm additive polimer PEG 4000 padabilangan Reynolds 8078 dapat menurunkan gesekan pada pipa stainless steelsebesar 65,27 persen, sedangkan dengan penambahan 200 ppm additive PEG4000 penurunan gesekannya 20 persen.;

---

ABSTRACT
Turbulent flow of dilute polymer polyethylene glycol (PEG)4000 solutionsin stainless steel pipes was studied. This experiment use stainless steel pipe withoutside diameter (OD) 5mm and inside diameter (ID) 3mm. Inside pipe roughnessis measured with relative roughness (k) 1.12 μm and 250, 500 and 1000 ppm foradditive concentration. The results show that flow properties are influenced bypolymer addition and surface roughness. In the turbulent flow regime withoutadditive, the increasing of friction coefficient appeared to be effected by wallcondition alone. Addition of polymer to water is effective for rough in stainlesssteel pipe. For example with addition of 600 ppm of polymer polymerpolyethylene glycol (PEG)4000 reduced drag in stainless steel pipe by 65,27percent at Reynolds number 8078, whereas in 200 ppm addition tested drag wasreduced only 20 percent., Turbulent flow of dilute polymer polyethylene glycol (PEG)4000 solutionsin stainless steel pipes was studied. This experiment use stainless steel pipe withoutside diameter (OD) 5mm and inside diameter (ID) 3mm. Inside pipe roughnessis measured with relative roughness (k) 1.12 μm and 250, 500 and 1000 ppm foradditive concentration. The results show that flow properties are influenced bypolymer addition and surface roughness. In the turbulent flow regime withoutadditive, the increasing of friction coefficient appeared to be effected by wallcondition alone. Addition of polymer to water is effective for rough in stainlesssteel pipe. For example with addition of 600 ppm of polymer polymerpolyethylene glycol (PEG)4000 reduced drag in stainless steel pipe by 65,27percent at Reynolds number 8078, whereas in 200 ppm addition tested drag wasreduced only 20 percent.]