Abstract: According to various embodiments, an additive manufacturing apparatus comprises a process chamber surrounding a print head, a recoat head, and a linear motion stage to which the print head and the recoat head are coupled. The print head and recoat head operate within the process chamber to build a three-dimensional object by depositing a build material and a binder material. The additive manufacturing apparatus further comprises a condenser system fluidly coupled to the process chamber to receive a gas stream with a first vapor content from the process chamber and provide the gas stream with a second vapor content to the process chamber. The second vapor content is less than the first vapor content. Additionally, the additive manufacturing apparatus comprises a blower fluidly coupled to the process chamber and the condenser to flow the gas stream through a closed loop comprising the blower, the process chamber, and the condenser.

Abstract: An additive manufacturing apparatus includes a process chamber having a length, a support extending along the length of the process chamber, a printing assembly, a vision system configured to image a dispensed binder pattern, and an electronic control unit communicatively coupled to the printing assembly, the first actuator, and the vision system. The electronic control unit is configured to cause the printing assembly to traverse the build zone in a forward or reverse direction while dispensing binder according to a programmed deposition pattern, receive image data from the vision system of the dispensed binder pattern resulting from the programmed deposition pattern, analyze the image data to determine whether there is an anomaly in the dispensed binder pattern, and in response to determining the anomaly in the dispensed binder pattern, adjust the programmed deposition pattern for a subsequent traversal of the printing assembly over the build zone to address the anomaly.

Abstract: A gas turbine engine thermal control double-wall apparatus for active clearance control and a method of using the apparatus are provided herein. The apparatus has a thermal air distribution manifold encircling an axially extending portion of an engine outer casing. The manifold has a plurality of header assemblies with an annular supply tube and a plurality of annular spray rails in fluid supply communication with at least one of the plurality of supply plenums. The annular spray rails define spray holes that are oriented to impinge thermal control air onto the outer casing having at least one thermal control ring attached thereto before being exhausted from circumferentially extending exhaust passages. All of the thermal control apparatus surfaces in direct contact with the thermal control air are constructed of an integrated double wall heat shield defining a hermetically sealed cavity between the walls therein.