One great source of understanding airflow beyond reference materials and books as noted is the development of C Class cat design and wings for them . One piece -two piece and 3 piece wing designs ,-zap flaps etc ,bendable twist type rigs -really interesting stuff.
check C class history and design articles.
Applied design and engineering theory and development of wing sails and slot effect.-with a healthy dose of inspiration and instictive insight added ,-a much overlooked aspect to our basic understanding .




Carl