Free Surface Flows under Compensated Gravity Conditions This book considers the behavior of fluids in a low gravity environment with special emphasis on application in PMD (propellant management device) systems. In the compensated gravity environment of a spacecraft the hydrostatic pressure decreases to very low values depending on the residual acceleration and surface tension forces become dominant. Consequently surface tension can be used to transport and position liquids if the residual acceleration and the resulting hydrostatic pressure are small compared to the capillary pressure. One prominent application is the use of PMDs in surface tens