How have you used SQL Server in your application?
In general, as long as your application can connect to an instance of SQL Server, you should be ok. You can do that by having it running somewhere on the network, as long as the network will allow connections to the database server from the computers where your application is installed. In most cases, that just means you need to make sure the network security allows traffic on the ports that your install of SQL Server is using, and that the application has the correct connection string - that is, one that includes the machine name, address or IP to find the database server on the network.