Definition of Reynolds number for MA side in Heat Exchanger (2P-MA) model

Hi.

I'm modeling the refrigeration cycle using simscape.

Condenser in the refrigeration cycle are considered as a Micro Channel Heat Exchanger(MCE) type.

I would like to use the specified correlation for the louver fin tube HX when modeling the heat transfer to the air side.

I want to set 'Flow geometry' to 'Generic' and then set 'a', 'b', and 'c' for the correlation.

However, the information of hydraulic diameter for the Reynolds number and the Prendtle number is not provided in the document.

Is it possible to use the hydraulic diameter calculated from '2 phase fluid 1'?

Does anyone know the definition of hydraulic diameter when using 'generic flow geometry' in heat exchanger block?

Thank you.

Best regards,

Answer 1

[Yifeng Tang]

I checked the source code: for generic geometry, the hydraulic diameter is calculated as

4 * generic_fluid_volume / generic_heat_transfer_area

Hope this answers your question.

For microchannel heat exchangers, my experience is also that the generic geometry version tends to give you the most flexible way to match to the reference data.