An energy efficient film comprising of first and second substrate layers and microstructures positioned between the first and second substrates is provided. The microstructures are positioned between the first and second structures such that a vacuum environment is created between the first and second substrates. In one embodiment, the insulating film includes a first substrate, a second substrate, and a plurality of microstructures positioned between the first substrate and the second substrate, such that a vacuum environment is created between the first and second substrates and within each microstructure cell, individually. Preferably, the plurality of microstructures is a polygonal cellular network positioned between a first transparent substrate and a second transparent substrate. A gasket may be provided on one or both of the first or second substrates. The gasket may also be provided on outer edges of the first and/or the second substrate.

A plugged honeycomb structure includes a honeycomb structure body, and a plurality of plugging portions, the honeycomb structure body further includes pass-through hole portions each of which is formed in at least a part of a partition wall intersection portion in which the partition walls intersect in one end face and each of which interconnects a pair of cells facing each other at a position corresponding to the partition wall intersection portion to enable pass-through of a fluid, and a value obtained by dividing a diameter of a first virtual inscribed circle inscribed at a position of a minimum hole width of the pass-through hole portion by a diameter of a second virtual inscribed circle inscribed at a position of a minimum plugging width between the plugging portions facing each other is in a range of 0.05 to 0.74.

Preforms including fiber reinforced nodes for use in fiber reinforced composite structures and methods for making fiber reinforced composite structures. Preforms with woven fabric elements extending radially from a common node include at least one reinforcing fiber interwoven between at least two elements and passing through the node. A method of assembling preform structures using the preforms to provide a structure with reinforced nodes.

A hierarchical sandwich core in the form of a honeycomb, i.e. having repetitive and periodic lattice materials. The sandwich core can be made up of a macroscopic honeycomb structure with sandwich cell walls having a mesoscopic cellular core. The longitudinal axis of cells of the mesoscopic honeycomb cell can be perpendicular to the longitudinal axis of the cells of the macroscopic honeycomb structure. Alternatively, if a foam core is used having mesoscopic cells the shape of the mesoscopic cells can be made during the foaming process so that they are elongate in a direction perpendicular to the longitudinal axis of the cells of the macroscopic honeycomb structure.

A first aspect of the present invention is a constant force compression construct, comprising: (a) a plurality of compressible layers, each compressible layer comprising a plurality of interconnected flexible struts configured as a regular hexagonal lattice of repeating unit cells, with the layers spaced apart from one another, and with the unit cells of each layer aligned with one another; and (b) a plurality of beams interconnecting each of the compressible layers with each respective adjacent compressible layer to form a three-dimensional lattice having an upper portion, a lower portion, and a compressible region therebetween, with the repeating unit cells contained in the compressible region.

A method and apparatus for fabricating a composite structure. The method comprises defining a shape for the composite structure with a first face sheet. The method places core sections on the shape defined by the first face sheet. The method places an adhesive in a group of joint cavities. The method places a second face sheet on the core sections placed on the first face sheet, wherein the first face sheet, the core sections, and the second face sheet, define a structural assembly in which the group of joint cavities are present. The method cures the structural assembly with the adhesive in the group of joint cavities to fabricate the composite structure in which the adhesive fills the group of joint cavities when the adhesive is cured.

A method and apparatus for fabricating a composite structure. The method comprises defining a shape for the composite structure with a first face sheet. The method places core sections on the shape defined by the first face sheet. The method places an adhesive in a group of joint cavities. The method places a second face sheet on the core sections placed on the first face sheet, wherein the first face sheet, the core sections, and the second face sheet, define a structural assembly in which the group of joint cavities are present. The method cures the structural assembly with the adhesive in the group of joint cavities to fabricate the composite structure in which the adhesive fills the group of joint cavities when the adhesive is cured.

A plugged honeycomb structure includes a honeycomb structure body, and a plurality of plugging portions, the honeycomb structure body further includes pass-through hole portions each of which is formed in at least a part of a partition wall intersection portion in which the partition walls intersect in one end face and each of which interconnects a pair of cells facing each other at a position corresponding to the partition wall intersection portion to enable pass-through of a fluid, and a value obtained by dividing a diameter of a first virtual inscribed circle inscribed at a position of a minimum hole width of the pass-through hole portion by a diameter of a second virtual inscribed circle inscribed at a position of a minimum plugging width between the plugging portions facing each other is in a range of 0.05 to 0.74.

A stacked cavity structure for arrangement on a mounting surface of a duct includes a support spine configured to be arranged on the mounting surface and extending into the duct with a longitudinal axis defining a longitudinal orientation. The stacked cavity structure includes a plurality of arms extending from the support spine and at least partially forming a plurality of overlapping cavities relative to the longitudinal orientation. Each of the plurality of arms includes at least a proximal first arm segment and a distal first arm segment.

A method for manufacturing a sound attenuation apparatus includes generating a three-dimensional digital model of the sound attenuation apparatus and manufacturing the sound attenuation apparatus based on the model using an additive manufacturing technique. The model includes a body with an interior extending between a bottom surface and a top surface; and a stacked cavity structure having a structure inlet; a passage extending from the structure inlet into the interior to a base surface within the interior of the body; a support spine formed within the interior; and a plurality of arms extending from the support spine and at least partially forming a plurality of overlapping cavities with cavity inlets fluidly coupled to the passage. Each of the plurality of arms include a proximal first arm segment extending from the support spine and a first distal arm segment oriented at an angle relative to the proximal first arm segment.