Petroleum: Empirical equations for thermal properties

Empirical equations for thermal properties

At a constant volume the heat of combustion of a petroleum product can be approximated as follows:

$Q_v = 12,400 - 2,100d^2$ .

where $Q_v$ is measured in cal/gram and d is the specific gravity at 60 °F (16 °C).

The thermal conductivity of petroleum based liquids can be modeled as follows:

$K = \frac{0.813}{d}[1-0.0203(t-32)]$ 0.547

where K is measured in BTU · hr⁻¹ft⁻² , t is measured in °F and d is the specific gravity at 60 °F (16 °C).

Specific heat

The specific heat of a petroleum oils can be modeled as follows:

$c = \frac{1}{\sqrt{d}} [0.388+0.00045t]$ ,

where c is measured in BTU/lbm-°F, t is the temperature in Fahrenheit and d is the specific gravity at 60 °F (16 °C).

In units of kcal/(kg·°C), the formula is:

$\frac{1}{\sqrt{d}} [0.402+0.00081t]$ ,

where the temperature t is in Celsius and d is the specific gravity at 15 °C.

The latent heat of vaporization can be modeled under atmospheric conditions as follows:

$L = \frac{1}{d}[110.9 - 0.09t]$ ,

where L is measured in BTU/lbm, t is measured in °F and d is the specific gravity at 60 °F (16 °C).

In units of kcal/kg, the formula is:

$L = \frac{1}{d}[194.4 - 0.162t]$ ,

where the temperature t is in Celsius and d is the specific gravity at 15 °C.

Petroleum