PengRobinson EOS in FPROPS - Revision history

Jpye: /* Overview */

2013-01-13T23:38:39Z

Overview

← Older revision		Revision as of 23:38, 13 January 2013
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	</math>		</math>

	It is sometimes more convenient to express the equation as a cubic polynomial in terms of compressibility factor <math>Z~~=\frac{p {\bar v}}{{\bar R} T}~~</math>		It is sometimes more convenient to express the equation as a cubic polynomial in terms of compressibility factor <math>Z</math>
	:<math>		:<math>
	Z^3+(-1+B)Z^2+(A-3B^2-2B)Z-(AB-B^2-B^3)=0		Z^3+(-1+B)Z^2+(A-3B^2-2B)Z-(AB-B^2-B^3)=0

2013-01-13T23:13:39Z

Overview

2013-01-13T23:08:31Z

Overview

← Older revision		Revision as of 23:08, 13 January 2013
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	It is sometimes more convenient to express the equation as a cubic polynomial in terms of compressibility factor <math>Z=\frac{p {\bar v}}{{\bar R} T}</math>		It is sometimes more convenient to express the equation as a cubic polynomial in terms of compressibility factor <math>Z=\frac{p {\bar v}}{{\bar R} T}</math>
	:<math>		:<math>
	Z^3+(-1+B)Z^2+(A-3B^2-2B)Z-AB+B^2+B^3=0		Z^3+(-1+B)Z^2+(A-3B^2-2B)Z-(AB-B^2-B^3)=0
	</math>		</math>
	in which		in which

2013-01-13T23:06:53Z

Overview

2011-08-16T17:49:09Z

Overview

← Older revision		Revision as of 17:49, 16 August 2011
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	\alpha &= \left( 1+\kappa \left( 1-\sqrt{\frac{T}{T_c}} \right) \right)^2 \\		\alpha &= \left( 1+\kappa \left( 1-\sqrt{\frac{T}{T_c}} \right) \right)^2 \\

	\kappa &= 0.37464+1.54226\omega - 0.26992\omega^2		\kappa &= 0.37464+1.54226\omega - 0.26992\omega^2 \\

			b &= \frac{0.0778\bar R T_c}{p_c}
	\end{align}		\end{align}
	</math>		</math>

2011-07-24T02:46:10Z

Overview

← Older revision		Revision as of 02:46, 24 July 2011
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	</math>		</math>

	It is sometimes more convenient to express the equation as a cubic polynomial in terms of compressibility factor <math>Z=\frac{~~PV_m~~}{RT}</math>		It is sometimes more convenient to express the equation as a cubic polynomial in terms of compressibility factor <math>Z=\frac{p {\bar v}}{{\bar R} T}</math>
	:<math>		:<math>
	Z^3+(-1+B)Z^2+(A-3B^2-2B)Z-AB+B^2+B^3=0		Z^3+(-1+B)Z^2+(A-3B^2-2B)Z-AB+B^2+B^3=0

2011-07-24T02:45:22Z

Overview

← Older revision		Revision as of 02:45, 24 July 2011
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	:<math>\begin{align}		:<math>\begin{align}

	a(T) &= 0.45724 \frac{{\bar R}^2{T_c}^2}{~~P_c~~} \alpha \left(T \right) \\		a(T) &= 0.45724 \frac{{\bar R}^2{T_c}^2}{p_c} \alpha \left(T \right) \\

	\alpha &= \left( 1+\kappa \left( 1-\sqrt{\frac{T}{T_c}} \right) \right)^2 \\		\alpha &= \left( 1+\kappa \left( 1-\sqrt{\frac{T}{T_c}} \right) \right)^2 \\

2011-07-24T02:43:32Z

Departure Functions

← Older revision		Revision as of 02:43, 24 July 2011
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	\end{align}		\end{align}
	</math>		</math>
	Clearly to evaluate these functions we need to be able to evaluate <math>\frac{da}{dT}</math>: (~~CHECK THIS~~)		Clearly to evaluate these functions we need to be able to evaluate <math>\frac{da}{dT}</math> (checked, agrees with Sandler):

	:<math>		:<math>
	\frac{da}{dT}= -0.45724 \frac{{\bar R}^{2} {T_c}^{\frac{3}{2}} }{p_c} \kappa \frac{\sqrt{\alpha} }{ \sqrt{T}}		\frac{da}{dT}= -0.45724 \frac{{\bar R}^{2} {T_c}^{\frac{3}{2}} }{p_c} \kappa \frac{\sqrt{\alpha} }{ \sqrt{T}}
	~~</math>~~

	~~Sandler seems to have:~~
	~~:<math>~~
	~~\frac{da}{dT}=- 0.45724 \frac{T_c^2 {\bar R}^{2}}{p_c} \kappa \left(\sqrt{\frac{\alpha}{T T_c}} \right)~~
	</math>		</math>

2011-07-24T02:42:59Z

← Older revision		Revision as of 02:42, 24 July 2011
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	Sandler seems to have:		Sandler seems to have:
	:<math>		:<math>
	\frac{da}{dT}=- 0.45724 \frac{T_c {\bar R}^{2}}{p_c} \kappa \left(\sqrt{\frac{\alpha}{T T_c}} \right)		\frac{da}{dT}=- 0.45724 \frac{T_c^2 {\bar R}^{2}}{p_c} \kappa \left(\sqrt{\frac{\alpha}{T T_c}} \right)
	</math>		</math>

2011-07-24T02:25:53Z

Departure Functions

← Older revision		Revision as of 02:25, 24 July 2011
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	</math>		</math>
	Clearly to evaluate these functions we need to be able to evaluate <math>\frac{da}{dT}</math>: (CHECK THIS)		Clearly to evaluate these functions we need to be able to evaluate <math>\frac{da}{dT}</math>: (CHECK THIS)

	:<math>		:<math>
	\frac{da}{dT}=- 0.45724 \frac{~~T_c~~ {\bar R}^{2}}{p_c} \kappa \~~left(~~\sqrt{\~~frac~~{~~T_c}~~{T}} ~~- 1\right)~~		\frac{da}{dT}= -0.45724 \frac{{\bar R}^{2} {T_c}^{\frac{3}{2}} }{p_c} \kappa \frac{\sqrt{\alpha} }{ \sqrt{T}}
	</math>		</math>

	Sandler seems to have:		Sandler seems to have:
	:<math>		:<math>