Yes, but you need to specify the vcloud-host, too.
You can try this:
var host = VclHostManager.getHostbyUrl("Your host URL");//get Organization by bame
var myOrg;for each (var org in host.getOrganizations()){ if(org.name == "Your Org name") { myOrg = org; break; }} //get vDC by name
var myOrg;for each ( var vdc in myOrg.getVdcs()){ if (vdc.name == "Your vDC name") { myVdc = vdc; break; }}
But in big environments it's better to use the query service.
Regards
Thomas