Spain - I'm American, wife is Turkish, getting spouse visa

[hurrikaane]

Me: US citizen, coming to Spain to work as an auxiliar for the Ministry of Education. I’ll have a long-stay visa, and soon after arrival a NIE.
Her: Turkish citizen, my fiancee, to be married in October in Istanbul (I get to Spain at the end of September). She has a US F1 visa (US long-term student visa). She was just recently awarded a 15 day visa to come to Barcelona for a conference (academic).

I’ll be in Madrid and as you can imagine I’ll want my wife (to be) to be able to visit me on a regular basis over the course of my 9-10 month stay. How easy is it to get her a visa that would accomplish this (e.g. a long-term multiple entry visa)? What is the process and particular visa we'd be looking for?

I've searched but found no info for our particular circumstance (both non-EU), most info out there is for couples with one EU partner.

Thanks for any help!