Abstract: A method for measuring the dynamic surface tension (DST) of a proposed outer layer of a liquid composition, to be curtain or slide hopper coated, over a range of surfactant levels to determine the surfactant concentration which produces the maximum resistance to air currents. Measurements are made by the Wilhelmy Blade Method, in which a surface of a pool of composition to be measured is placed in contact with the lower edge of a suspended blade. The static method is modified such that the surface of the composition touching the blade is continually refreshed to simulate the formation of fresh curtain surface by pumping the composition upwards through an open cylinder and allowing the composition to spill over the edges (“overflowing weir”). The bulk surfactant concentration providing maximum resistance to coated streakiness or mottle is highly correlated with the concentration providing maximum surface tension gradients in the overflowing weir apparatus.

Abstract: A method for measuring the dynamic surface tension (DST) of a proposed outer layer of a liquid composition, to be curtain or slide hopper coated, over a range of surfactant levels to determine the surfactant concentration which produces the maximum resistance to air currents. Measurements are made by the Wilhelmy Blade Method, in which a surface of a pool of composition to be measured is placed in contact with the lower edge of a suspended blade. The static method is modified such that the surface of the composition touching the blade is continually refreshed to simulate the formation of fresh curtain surface by pumping the composition upwards through an open cylinder and allowing the composition to spill over the edges (“overflowing weir”). The bulk surfactant concentration providing maximum resistance to coated streakiness or mottle is highly correlated with the concentration providing maximum surface tension gradients in the overflowing weir apparatus.

Abstract: The present invention minimizes the effects of capillary and inertial forces on the film profile for a slide hopper, thereby making the film profile smooth and predictable even when the transition section is short. The invention enables improved coating uniformity over the main width of the coating and particularly at the edges. The slide hopper has a slide surface and a lip surface, with a transition surface connecting the two surfaces. The transition surface profile has a variable curvature that is zero at the first end, increases continuously to a maximum at point between the first and second ends and decreases continuously to zero at the second end.

Abstract: A separator for removing frozen or condensed water from an air stream, such as to aircraft environmental and avionics cooling systems, is described which comprises a generally tubular housing having an inlet and outlet, one or more flexible disks and baffle plates disposed in preselected spacing within the housing to define a tortuous air path therethrough, a motor, such as in the form of a magnetic pulse solenoid, operatively connected to each disk for controllably flexing each disk whereby moisture deposited on the disk is removed, and a conduit operatively connected to the housing for draining moisture therefrom.

Abstract: A separator for removing frozen or condensed water from an air stream, such as to aircraft environmental and avionics cooling systems, is described which comprises a generally tubular housing having an inlet and outlet, one or more screens of selected mesh size disposed in preselected spacing generally transverse of a direction of air flow within the housing, a brush or wiper disposed against each screen for removing moisture from each screen, either the screen or contacting brush being rotatable relative to the other, a motor operatively connected to the rotatable screen or brush for rotating one against the other to remove moisture from the screen, and a conduit operatively connected to the housing for draining moisture therefrom.