Abstract:
A supporting device and method for a large thin-walled part is disclosed. The supporting device comprises a processing device and a supporting device. A workpiece is positioned between the processing device and the supporting device and is clamped at a periphery in a flexible clamping mode. A cutter in the processing device is connected with an iron core. A coil is wound on the iron core. When the coil is energized, a magnetic field is generated around the coil. A blade part of the cutter is in contact with a processing side of the workpiece. The supporting method combines the magnetorheological fluid technology with the jet supporting technology, and uses a jet impact force to offset part of a milling force. The current magnitude and winding mode of the coil are changed to control magnetic field intensity. The magnetorheological fluid is cured instantly to support the workpiece.
Abstract:
A method for determining a reduction factor of a bearing capacity of an axial load cylindrical shell structure relates to stability checking of main bearing strength thin-walled members of aerospace and architectural structures. Different from experiment experience-based conventional defect sensitivity evaluating method represented by NASA SP-8007, a depression defect is introduced in a manner of applying a radial disturbance load. First, an influence rule of a depression defect amplitude of a single point to an axial load bearing capacity is analyzed by using numerical values, so as to determine a load amplitude range; then, defect sensitivity analysis is performed on depression defects of multiple points; then, experiment design sampling is performed by using load amplitude values and load position distribution as design variables; and finally, based on optimizing technologies such as an enumeration method, a genetic algorithm and a surrogate model, the most disadvantageous disturbance load of the multiple points that limits the defect amplitude is searched for, and a reduction factor of the bearing capacity of the axial load cylindrical shell structure is determined, so as to establish a more physical method for evaluating the defect sensitivity and the bearing performance of the axial load cylindrical shell structure.