Hi Everyone
I Am trying to create thermodynamic properties for a certain fluid (NOVEC 649). I have all the fluid properties I need except one, stated below
1. partial derivative of pressure with respect to the specific volume at a constant temperature δP/δv)T (P, T)
However, I have data for partial derivative of pressure with respect to the density at a constant temperature δP/δrho)T (P, T).
Therefore if Volume (V) =1/Density (rho), could you kindly guide me on how I can obtain δP/δv)T (P, T) using the density.
Or any equation that I can use to obtain δP/δv)T (P, T) since I have value for V,P, and T in the attached document
The table is very long but I have attached just 3 steps for you to use as a guide
Thank you for your anticipated response
Dear Mustafa Abba Imam ,
Plot the data on the graph of P vs V. Once this exercise is completed, connect all the points with same temperature as curves. You will get the characteristics of the fluid. From these curves the slopes can be calculated. Also a curve fit equation can also be derived.
check this graph for reference
Article Pressure-Volume-Temperature Relationships of Liquid Normal Deuterium1
dv = d(1/rho) = -d rho/ rho^2 Thus, just use that directly for dp/dv
Dear Mustafa,
Unfortunately there is no straightforward procedure to solve your problem. Given that shortage, I suggest you to follow the advice of Syed.
1.Applying the general law of gases P V=nRT you can find dp/dV
2. There are a text Book of numerical values of Pressure and specific volume at a constant temperature and then make your simulation of numerical data
Thank you everyone, for your quick responses, I really appreciate
Follow the Fillipo's answer. Simply apply the chain rule of differentiation:
dp/dv=dp/drho*(drho/dv)=dp/drho*(-1/v^2)=-rho^2*dp/drho
plz use maxwell's equations - which can be obtained interms of measurable h,s,T
- Badges
- Science topic
- Similar topics
- Control Systems Engineering
- Filtering