Question

the above question must be solved using the supplied viscosity table. but I keep getting weird values.
can I please have workings and explanation as how to use this table please.
thank you

Question 3 (3 Marks) Consider a journal bearing with the following characteristics: . Radius of 0.02m A clearance of 0.1mm . .A length of 0.02m Running under the following conditions: .Using SAE40 oil for lubrication . Running at 50 rps . Subject to a load of 100N If the temperature of the oil fluctuates from 15 to 40 degrees Celsius, then what is the fluctuation in the coefficient of friction in the bearing? Temperature F) 140 160 180 200 220 240 260 280 80 100 120 1o3 10 10 0.9 0.7 0.6 0.5 0.4 0.3 10 20 30 40 50 60 70 809 100 110 120 130 140 Temperature ("O oil must satisfy the 10W viscosity requirement at-18°C and the SAE 40 ment at 100°C

Answer 1

This is very interesting problem where viscosity of the oil is changing with the temperature. It is clearly given in the problem that we are using SAE40 oil. Now we will solve the problem corresponding to this oil only.

Please refer to the pic below for detailed solution.

2000 G 100- o c Temperature ("C ) → (above Trope 9telerrin)も 7'아', provid.J es.ht am com 9melen on cleasl esecan see leai c e quesion ven in O.1 too D emabh (R) (u/) load = toon

c ton (a) becoting i givenb Coericion here nspeed (Rev per sec) ρ= bearing pre-sur e 10 0 X (o.o2 P125,00o Pa Pa 3 굿 ( 2000X10 50 2500o o.o2 uE3.15 827 10 la- s ,2 (100x16" x50へ( 0. 02 12500 o fuction r, fom 3.15627 1o 0.15 .". toe