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We present an optical technique that combines simultaneous planar laser-induced fluorescence (PLIF), particle tracking velocimetry (PTV) and infrared (IR) thermography for the space-and time-resolved measurement of the film-height, 2-D velocity and 2-D free-surface temperature in liquid films falling over an inclined, resistively-heated glass substrate. Using this information and knowledge of the wall temperature, local and instantaneous heat-transfer coefficients (HTCs) and Nusselt numbers, Nu, are also recovered along the waves of liquid films with Kapitza number, Ka= 180, and Prandtl number, Pr= 77. By employing this technique, falling-film flows are investigated with Reynolds numbers in the range Re= 18–66, wave frequencies set to f w= 7, 12 and 17 Hz, and a wall heat flux set to q ̇= 2.5 W cm− 2. Complementary data are also collected in equivalent (ie, for the same mean-flow Re) flows with q ̇= 0 W cm …