Yes, as joey says all the food and drink is free.
This page has details of all the spa/hair services and prices for those which aren't free.
http://www.virgin-atlantic.com/gb/en/tr ... w/spa.htmlThe Clubhouse can get very busy in the evenings as that's when a lot of the VS flights leave, so if you want a spa treatment or haircut book as soon as you arrive.
Otherwise eat and drink to your heart's content! There's a full service bar & brasserie as well as a deli counter with breads, meats, cheeses, salads etc.
On your return from Mumbai you'll be able to use the Revivals Lounge, after immigration, baggage reclaim & customs in LHR T3 arrivals. There you can have a shower, cooked breakfast and limited range of spa treatments.
Enjoy!