Hello,

creating a custom fuel blend in Converge CFD typically requires inputting thermophysical properties such as density, viscosity, surface tension, specific heat, thermal conductivity, and vapor pressure, among others. However, obtaining these properties for hydrous ethanol can be challenging as you mentioned.

For hydrous ethanol, you can use available thermophysical property data for anhydrous ethanol and water, as well as their mixture properties. You can find this information in the literature, scientific databases, or online sources. For example, NIST (National Institute of Standards and Technology) provides a web-based tool called "NIST Chemistry WebBook" that has thermophysical property data for various chemicals, including anhydrous ethanol and water. The web address for this resource is: https://webbook.nist.gov/chemistry/

Once you have the data for anhydrous ethanol and water, you can estimate the properties of hydrous ethanol using mixing rules, such as the volume-weighted average or mass-weighted average, depending on the property being estimated. You may need to consult the literature or consult a chemical engineering textbook to determine the appropriate mixing rules for each property.

For example, to calculate the density of hydrous ethanol using volume-weighted averages, you can use the formula:

ρ_mix = x₁ρ₁ + x₂ρ₂

where ρ_mix is the density of the mixture, ρ₁ and ρ₂ are the densities of ethanol and water, respectively, and x₁ and x₂ are the volume fractions of ethanol and water in the mixture.

Keep in mind that this approach has its limitations, as it does not account for any interactions between ethanol and water that could influence the properties of the mixture. Nevertheless, it can provide a reasonable starting point for your simulations in Converge CFD.

Once you have calculated the necessary properties, you can input them into Converge CFD to create a custom fuel blend. Refer to the Converge CFD documentation or user manual for guidance on how to input custom fuel properties.

Thank you very much for this important information...best regards

You are welcome Bakache Younes.

God bless you ,you open for me a new horizon and prospects

Best Regards