The effect of injecting small bubble air into the water stream flowing in two spiral arrangement copper tube 15 m length, 0.012 diameter, and number coils were 11 has been investigated. inner surface solar collector was also painted with a matte black paint mixture nanomaterial (thermal dye 5% TiN). performance examined experimentally Babylon-Iraq, longitude (44.4 E) latitude (32.4 N) under bes...