There is no limit to the temperature allowed in the thermal liquid domain, regardless of whether used with purely Foundation Library blocks in Simscape or with blocks from Simscape Fluids. If no Thermal Liquid Settings block is connected to a network, the domain defaults will be used (water). By connecting the Thermal Liquid Settings block, one can specify fluid properties, including max and min temperature and pressure. Simscape Fluids has a Thermal Liquid Properties block with some preloaded fluid properties.
If you need to include vaporization effects, consider using the two-phase domain.
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