52results about How to "Guaranteed normal start" patented technology

The invention discloses an electromagnetic switch protective structure and a mounting method thereof. The electromagnetic switch protective structure comprises an electromagnetic switch body (1), a guide cylinder (2) mounted on the electromagnetic switch body (1), and an movable iron core draw bar (3) mounted on a movable iron core end surface (8). The guide cylinder (2) is provided with a U-shaped positioning snapping groove (4), and the movable iron core draw bar (3) is provided with a positioning snapping groove (5). The electromagnetic switch protective structure also comprises a bowl-shaped rubber sealing cover (6), the bottom of the bowl-shaped rubber sealing cover (6) is provided with a central hole, the portion of the central hole is snapped inside the positioning snapping groove (5), and an opening end is mounted inside the U-shaped positioning snapping groove (4). According to the electromagnetic switch protective structure, the U-shaped positioning snapping groove and the positioning snapping groove achieve the positioning of the bowl-shaped rubber sealing cover and further achieve the sealing of the periphery of the guide cylinder to complete the protection to the movement of the movable iron core of an electromagnetic switch; meanwhile, an air exhaust device on the bowl-shaped rubber sealing cover can well release the negative pressure of the electromagnetic switch.

The invention relates to a two-dimensional blade profile optimization method for a compressor considering a low Reynolds number working performance; the optimization method is characterized by comprising the following steps of: step 1: analyzing the meridional flow performance of a prototype multistage axial flow compressor at different rotating speeds; step 2: determining a key two-dimensional blade profile section to be optimized; step 3: performing parametric fitting to the key two-dimensional blade profile in step 2; step 4: analyzing the aerodynamic performance of the two-dimensional blade profile, and analyzing the aerodynamic performance of the parameterized two-dimensional blade profile to obtain the variable attack angle performance of the blade profile under a low Reynolds numberworking condition and the variable attack angle performance under a high Reynolds number working condition; and step 5: optimizing the modeling parameters of the two-dimensional blade profile, adjusting the two-dimensional modeling parameters according to the variable attack angle performance parameters of the two-dimensional blade profile obtained in step 4 at different Reynolds numbers, using agenetic algorithm to circularly iterate steps 3 and 4 until a two-dimensional blade profile design reducing loss and increasing stall margin is obtained, and then obtaining a new two-dimensional blade profile. According to the invention, the performance optimization of the two-dimensional blade profile of the axial flow compressor at different Reynolds numbers and different attack angles is realized; the designed working performance of the compressor is improved while the aerodynamic performance of the compressor at the low rotation speed working condition is improved; and the flow efficiencyis improved while the normal starting and stable working of the compressor are ensured.

The invention discloses a regulation device with a symmetric type variable structure for a supersonic inlet. The regulation device comprises a front body compression plate, a throat upper panel, a combustion chamber upper panel, regulation devices and sliding mechanisms, wherein the front body compression plate and the combustion chamber upper panel are connected with the throat upper panel through the sliding mechanisms and the regulation devices; the regulation devices are symmetrically fixed to the throat upper panel; and a plurality of sliding mechanisms are symmetrically installed on the front body compression plate and the combustion chamber upper panel respectively. According to the regulation device, through the regulation devices, the size of a compression angle of an inlet duct and the height of a throat are changed, the quality and the air flow of an airflow which enters a combustion chamber, and the inlet duct is in a better working state; when the inlet duct works at a low Mach number, the compression angle of the front body compression plate is reduced, and meanwhile, the height of the throat is increased so as to change the starting performance of the inlet duct and improve the performance of an engine; and along with increase of the Mach number, the compression angle is increased, the height of the throat is also reduced, the internal contraction ratio is increased, the static pressure at the outlet of the inlet duct is strengthened, and the overall performance of an aircraft is improved.