Temperature depence of viscosity of a polymer 1

[bauer1989]

Hi,

I am working on the temperature dependence of viscosity of a polymer.

I would like to model it on ANSY FLUENT et plot a curve on excel.

My problem is within the Arrhenius law:
nu = K*gamma^(n-1)*exp[alpha(1/(T-To) - 1/(T-Talpha)]
I don't get the difference between temperatures To and Talpha.
It says that the both are reference temperature, but i would to know the difference.


Thanks in advance fro your help.

 

[BigInch]

To model viscosity change with temperature you must know the value of viscosity at two different temperatures.
So, I would think that there are two reference viscosities (two values) which are each given at their respective reference temperature, To and Ta.

Technology is stealing American jobs. Stop H1-Bs for robots.

 

[jari001]

https://www.sharcnet.ca/Software/An...c_newton_theory_viscosity_non_isothermal.html

Some quick research found the above link and it offers one interpretation for To and Talpha.

 

[BigInch]

jari, Thanks (*). I learned something from that.

Technology is stealing American jobs. Stop H1-Bs for robots.

 

[jari001]

Glad to be of some help =)
Hopefully, the OP learned what they were looking for too!

 

[BigInch]

Never know. You can lead a horse to water, but you can't make them drink.

Technology is stealing American jobs. Stop visas for robots.

 

[georgeverghese]

The last time I got tangled up in a similar situation with bitumen, none of the equations I could get my hands on would cover the entire temperature range with reasonable accuracy. I had to derive a polynomial expression myself, and also break up the curve into 3 temperature ranges, with a different polynomial expression for each range. Things get a little easier when you have Mathcad to help.

 

[BigInch]

I normally use the Andrade equation, but my typ fluids are the more conventional oils and petro products. I thought it could have been similar to that.

Technology is stealing American jobs. Stop visas for robots.