Valencia CF has been placed in pot number 2 and this is the pot with the slightly weaker teams historically that the teams in the first pot. Valencia CF won't end up playing against Spanish teams, at least not in the group stages or the first knockout round. Overall there are 4 pots.
Here is Pot 2: Valencia, Benfica, Shakhtar Donetsk, Zenit St. Petersburg, Schalke 04, Manchester City, Braga, Dinamo Kiev
Here are the possible Valencia CF opponents:
Pot 1: Chelsea (ENG), Manchester UTD (ENG), Bayern Minhen (GER), Porto (POR), Arsenal (ENG), Milan (ITA).
Pot 3: Ajax (HOL), Olympiakos (GRE), Juventus (ITA), Anderlecht (BEL), Spartak Moskva (RUS), PSG (FRA), Lille (FRA), Galatasaray (TUR).
Pot 4: Celtic (SCO), Nordsjiland (DEN), Montpellier (FRA), Dinamo Zagreb (CRO), Cluj (ROM), Bate Borisov (BLR), Borusia Dortmund (GER).