Numerical simulation are conducted to explore the characteristics of the axial inflow and related aerodynamic noise for a large-scale adjustable fan with the installation angle changing from−12°to 12°.In suc...Numerical simulation are conducted to explore the characteristics of the axial inflow and related aerodynamic noise for a large-scale adjustable fan with the installation angle changing from−12°to 12°.In such a range the maximum static(gauge)pressure at the inlet changes from−2280 Pa to 382 Pa,and the minimum static pressure decreases from−3389 Pa to−8000 Pa.As for the axial intermediate flow surface,one low pressure zone is located at the junction of the suction surface and the hub,another is located at the suction surface close to the casing position.At the outlet boundary,the low pressure is negative and decreases from−1716 Pa to−4589 Pa.The sound pressure level of the inlet and outlet noise tends to increase monotonously by 11.6 dB and 7.3 dB,respectively.The acoustic energy of discrete noise is always higher than that of broadband noise regardless of whether the inlet or outlet flow surfaces are considered.The acoustic energy ratio of discrete noise at the inlet tends to increase from 0.78 to 0.93,while at the outlet it first decreases from 0.79 to 0.73 and then increases to 0.84.展开更多
Turbine generators play a pivotal role in efficiently converting gas internal energy into electrical energy,finding extensive applications in diverse green energy and power equipment.The adoption of a high-speed direc...Turbine generators play a pivotal role in efficiently converting gas internal energy into electrical energy,finding extensive applications in diverse green energy and power equipment.The adoption of a high-speed direct-drive structure eliminates mechanical losses associated with the reducer between the turbine and generator,enhancing system efficiency and compactness.However,this configuration introduces challenges in design and manufacturing.This article explores the various application scenarios of high-speed direct-drive power generation systems,examining their roles in organic Rankine cycle power generation,gas turbine power generation,supercritical CO_(2) power generation,vehicle exhaust turbine power generation,and natural gas pressure reduction power generation.Considering the high-speed,high-pressure,high-temperature,and high-efficiency challenges in turbine power generation systems,the key technologies are reviewed including high-speed bearings,rotor dynamics,high-speed motors,high-frequency variable frequency technology,sealing technology,axial force adjustment,thermal management,turbine aerodynamic design,and system control strategies.The article further delves into the current research and development status of high-speed direct-drive power generation systems across different application scenarios.Finally,the article presents prospects for the future development of efficient,reliable and widely adaptable high-speed direct-drive generators,offering valuable insights for researchers and practitioners in the field.展开更多
基金supported by Key Research and Development Project of Shandong Province[2019GSF109084]Young Scholars Program of Shandong University[2018WLJH73].
文摘Numerical simulation are conducted to explore the characteristics of the axial inflow and related aerodynamic noise for a large-scale adjustable fan with the installation angle changing from−12°to 12°.In such a range the maximum static(gauge)pressure at the inlet changes from−2280 Pa to 382 Pa,and the minimum static pressure decreases from−3389 Pa to−8000 Pa.As for the axial intermediate flow surface,one low pressure zone is located at the junction of the suction surface and the hub,another is located at the suction surface close to the casing position.At the outlet boundary,the low pressure is negative and decreases from−1716 Pa to−4589 Pa.The sound pressure level of the inlet and outlet noise tends to increase monotonously by 11.6 dB and 7.3 dB,respectively.The acoustic energy of discrete noise is always higher than that of broadband noise regardless of whether the inlet or outlet flow surfaces are considered.The acoustic energy ratio of discrete noise at the inlet tends to increase from 0.78 to 0.93,while at the outlet it first decreases from 0.79 to 0.73 and then increases to 0.84.
基金supported by the National Major Science and Technology Project (2019-Ⅱ-0009-0029)the 2022 Jiangsu Province Carbon Peak Carbon Neutral Science and Technology Innovation Special Major Innovation Carrier Construction Project (BM2022001)+2 种基金the National Natural Science Foundation of China(52202324)supported by the Hundred Talents Program of the Chinese Academy of Sciencesthe Nanjing Future Energy System Research Institute independently deploys research projects (E3550101)
文摘Turbine generators play a pivotal role in efficiently converting gas internal energy into electrical energy,finding extensive applications in diverse green energy and power equipment.The adoption of a high-speed direct-drive structure eliminates mechanical losses associated with the reducer between the turbine and generator,enhancing system efficiency and compactness.However,this configuration introduces challenges in design and manufacturing.This article explores the various application scenarios of high-speed direct-drive power generation systems,examining their roles in organic Rankine cycle power generation,gas turbine power generation,supercritical CO_(2) power generation,vehicle exhaust turbine power generation,and natural gas pressure reduction power generation.Considering the high-speed,high-pressure,high-temperature,and high-efficiency challenges in turbine power generation systems,the key technologies are reviewed including high-speed bearings,rotor dynamics,high-speed motors,high-frequency variable frequency technology,sealing technology,axial force adjustment,thermal management,turbine aerodynamic design,and system control strategies.The article further delves into the current research and development status of high-speed direct-drive power generation systems across different application scenarios.Finally,the article presents prospects for the future development of efficient,reliable and widely adaptable high-speed direct-drive generators,offering valuable insights for researchers and practitioners in the field.
