Droplet spreading on flat non-reactive surfaces is established; however, porous surfaces present a complicated case. Wetting of porous surface involves the simultaneous spreading and penetration of the droplet. The effect of low impact velocity (i.e <1 m/s) on dimensionless droplet diameter and dynamic contact angle has been experimentally observed in this study. Low impact velocity helps reducing the penetration of droplets into the droplets in case of porous substrates. In the low impact

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... ity range, the effect on contact angle is not significant. Dimensionless droplet diameter also shows similar behavior. Index Terms-Contact angle, wetting, porous surface, droplet impact velocity.