I Googled for that case, looks like the front fans might even be sealed and not providing much (if any) external air into the case.
This is going to be a lesson in how cooling and airflow works.
I don't even know how to respond to this - it is the kind of poor information that we are constantly trying to correct. Fans will add noise, yes. This can be mitigated with fan curves or fans that are more silent than others. Not all fans are created equal. However, omitting the fans will be worse for cooling than having fans that make some noise.
You cannot have a perfectly 'silent' case and have 'a good cooling' case unless you have some large fans that spin slowly and the case itself has very good airflow properties. Having fans inside of a closed box means you just have yourself a box that moves hot air around inside...getting hotter and hotter.
Air has to constantly be exchanged with cool, ambient air in order for a case to be functional as part of the cooling process. A sealed box cannot cool and a case that lacks fans to exchange/move air allows for poor thermal exchange.