Designing a novel cooling system for spacecraft calls for special devices for heat removal in the open space. As a fundamentally novel element of the space power plant, it is proposed to use a drop cooler-generator, the basic units of which are a generator of a droplet sheet and a drop catcher. The drop generator creates a directed motion of a monodisperse medium of fine drops of the hot liquid coolant. A steady motion of the drops of a vacuum oil is organized in the open space, so that the drops lose a fixed amount of heat due to radiation. The cooled droplets are collected in the drop catcher and the oil is returned to the working duct of the space power plant. The process of cooling a moving sheet of monodisperse oil droplets is considered in the open space conditions. Using the model of an optically thick layer, the heat influx equation for the droplet sheet is derived. Temperature fields of droplets at different distances from the drop generator are calculated. The method of collecting the drops using a drop catcher consisting of a funnel and an outlet channel is proposed. It is assumed that a moving liquid film is formed on the inner surface of the drop catcher due to the inertia of the droplets depositing on the film. An asymptotic model of an oil film flow in the drop catcher is constructed. Simplified Navier - Stokes equations are solved in a thin film of unknown thickness, at the outer boundary of which the balance conditions for the mass, momentum, and energy fluxes are specified. A parametric numerical study of the profiles of velocity, temperature, and film thickness is performed. Three-dimensional effects caused by the deviation of the drop stream from the drop catcher axis are examined.
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