A unit cylinder cell model with a body-fitted coordinate system is employed to analyze the hydrodynamics and heat transfer associated with steam condensation on a spray of equal sized water droplets. The droplets are assumed to be moving in the intermediate Reynolds number regime, Re-g = O(100). The distance between neighboring droplet centers is allowed to be arbitrary in the plane of motion, but the droplets are assumed to be uniformly spaced in the plane perpendicular to the direction of motion. Furthermore, once a particular cofiguration of the droplets is set, the subsequent spacings between the droplet centers in that configuration are taken to remain constant during the entire condensation process. The formulation entails a simultaneous numerical solution of the quasi-steady elliptic partial differential equations that describe the flow field in both the dispersed and continuous phases in each cell. In part I of this study, the results for the velocity, surface pressure and drag are presented. In part II of this study, the results for the condensation induced velocities, surface shear stress, the Nusselt number and the Sherwood number are provided. In both parts of the study, the interactions between neighboring drops have been examined.