What is ....

[BOBISTHEOILGUY]

1- Viscosity?

and as the temperature of a lubricating oil increases, what effect does this have on the oil's viscosity and density?

 

[Patman]

The viscosity of an oil is measured by the amount of time it takes to flow, or in simpler terms, it's thickness. As an oil gets hotter, it gets thinner, and when measured, it will flow faster. Many people think multigrade oils such as 10w30, actually get thicker when hot, but this is simply not the case. All oils will always thin out when warmer.

 

[RB Shannon]

As the temerature increases the density will decrease indicated by a thinner viscosity

 

[MolaKule]

Density is the volume occupied by a specified mass, measured in kg/m^3, in the SI system.

 

[RB Shannon]

Your right,the density would increase with an increase in temps,and the molecule's would spread out showing as a decrease in viscosity

 

[Jay]

The density would be the same wouldn't it? Oil doesn't weigh less as it warms.

 

[Jay]

No, wait. The density would decrease because the volume increases as it warms.

 

[RB Shannon]

I,m getting all screwed up

Density is the mass or weight per unit of volume, so therefore as the temperature increases the volume would increase,so the oil would be less dense at a higher temp.

 

[BOBISTHEOILGUY]

Guess I better get this one overwith before you smoke something up there...

First question.. what is viscosity..given answer is Measurement of a fluids resistance to flow

Second question..what effect on oils viscosity and density..Both decrease

 

[BOBISTHEOILGUY]

what about the density?

 

[arihel]

Viscosity: a fluid resistance to flow.
For the second part, i have always tought that, when anything gets hotter, it increases its volume,(forget about water around 4C and some other weird things) for a fluid, the volume increase allows the molecules to move easily, and then decrease the resistance to flow.
Since by definition density is mass/volume, when we have a higher volume, the results from this division, are smaller, then, when temperature increases, density and viscosity decrease.
(My apologies if there are grammar or syntax mistakes)