Hello 忠宇,
You are right that evaporative condenser isn't available from Simscape Fluids. Modeling such type of heat exchanger will require some customization (and creativity ;), and I feel like it's do-able. But I'll need to understand the thermodynamic process of such an equipment to be sure. If you are willing to provide more insights and hear about some modeling ideas I have in mind, please kindly reach out to your local MathWorks support team, mention this conversation, and ask them to route this request to me.
Thanks,
Yifeng