摘要:
An improved method and apparatus for actively controlling a combustion process such as a waste incinerator by means of a spatial and temporal synchronized injection of fuel. The improved method and apparatus employs an active control system which controls the intentional formation of large scale, coherent vortices and the synchronized injection of the fuel supply at various locations relative to the formation of the vortices. The preferred apparatus comprises an actuator or similar structure that is adapted for producing and stabilizing discrete, large scale vortices in a combustion device. In addition, another device controls or modulates the injection of the fuel into the vortices at the optimal location and timing relative to the vortex cycle. As applied to an incinerator, this method can be optimized to ensures that the fuel and waste are introduced into the highest temperature locations, were extended residence times are obtained by trapping the fuel and waste inside the vortices. A high combustion efficiency may also be achieved by actively synchronizing the periodic fuel injection with the formation of the vortices.
摘要:
The oscillations found to occur in the cavities of an structural frame moving through a fluid are substantially eliminated by the adoption of perturbation elements located at the leading edge of the cavity and reflecting any remaining oscillations out of the cavity at the trailing edge. The perturbation elements may take the form of multiple pins of various shape and geometrical arrangement which prevents the generation and growth of vortices causing acoustic oscillations. The reflection of remaining oscillations out of the cavity may be accomplished by ramping the trailing edge of the cavity.
摘要:
A punch has a punch tip with a shank and a punch pad with an orifice for receiving the shank. The punch pad includes a hole positioned closely adjacent the orifice to define a thin wall between the hole and the orifice. The thin wall has a slot which extends through its thickness to define at least one, and preferably two, tabs. An insert, which may be a pin, is provided for insertion into the hole and deforming the tab into supportive, retaining contact with the shank of the punch tip within the orifice. The shank of the punch tip may be provided with a shoulder for abutting the inwardly deformed tab or tabs to restrain withdrawal of the punch tip from the punch pad during operation.
摘要:
The invention is directed to a fluid mixing device in which a jet of firstluid is passed through a nozzle having a conical inlet section and a noncircular, elongated, exit section. The jet of first fluid mixes with a second fluid located downstream of the device. In operation, the intersection of the conical and elongated sections produces axial rotation in the first fluid. Intense, three-dimensional, axial and circumferential vortical structures are created. These structures then interact with the high modes of azimuthal instabilities that are common to the elongated configuration. The jet of first fluid evolves into two secondary jets, generating a double shear layer inside the flow. Highly efficient mixing of the fluids, in both the outside and inside (core) segments of the jet, is achieved within a relatively small mixing space.