How are modelers getting transcritical compressor capacity coefficients when modeling CO2 transcritical booster systems?

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I can calculate transcritical compressor capacity and performance at specific points, but I haven't been able to get the 10 capacity coefficients for transcritical compressors operating in transcritical mode for compressors I'm modeling for use in OpenStudio. I reached out to Bitzer and was told they're not yet available. Does anyone have a solution for this?