Aerodynamic design of convertible prop-rotor is a challenging and complex task.Instead of focus on a design condition,prop-rotor are requested to attain good performance in wide range of operating conditions.In presen...Aerodynamic design of convertible prop-rotor is a challenging and complex task.Instead of focus on a design condition,prop-rotor are requested to attain good performance in wide range of operating conditions.In present work,to further improve performance of prop-rotor under each operating condition,the concept of variable-pitch proprotor has been proposed.However,a compromising aerodynamic design of prop-rotor is inevitable,due to discrepancy of operating condition.Consequently,a multi-objective optimization is implemented with genetic algorithm.Factors which has significantly influenced on aerodynamic characteristics of prop-rotor are employed as design variable.To avoid expensively computational cost,two theories has been implemented and validated while it able to provide a promising result without high consuming of time.Eventually,several designed individuals within different performance has been analyzed and discussed.Subsequently a calculation of aerodynamic characteristic with highfidelity solver has been conducted as validation for designed individual.展开更多
为了解决某电厂直吹式制粉系统阻力大、出力不足、制粉单耗高、分离器效率低、挡板调节性能差、煤粉细度不合格、磨损严重等问题,基于先进的旋涡理论,采用气固分离技术,对影响分离器性能的关键因素进行深入研究,设计出以旋风分离为主、...为了解决某电厂直吹式制粉系统阻力大、出力不足、制粉单耗高、分离器效率低、挡板调节性能差、煤粉细度不合格、磨损严重等问题,基于先进的旋涡理论,采用气固分离技术,对影响分离器性能的关键因素进行深入研究,设计出以旋风分离为主、惯性分离为辅的旋惯耦合粗粉分离器,并成功应用,同时对分离器出口煤粉输送管道进行优化改造。结果表明:该直吹式制粉系统优化改造后,分离器分离效率提高13.3%,制粉出力增加20%,制粉单耗下降4.73 k W·h/t。展开更多
In this study, a new high-precision numerical simulation scheme for vortical flows (vortex-based scheme) is proposed. This scheme identifies a vortical flow in each computational cell, and then, reconstructs a vortica...In this study, a new high-precision numerical simulation scheme for vortical flows (vortex-based scheme) is proposed. This scheme identifies a vortical flow in each computational cell, and then, reconstructs a vortical velocity distribution based on the Burgers vortex model. In addition, a pressure distribution in the vicinity of the vortex center is also reconstructed. The momentum transfer is calculated with the reconstructed velocity and pressure distributions, and therefore, the vortex-based scheme can simulate vortical flows more accurately than the conventional schemes. In fact, as the simulation result of inviscid vortex attenuation problem, the vortex-based scheme shows lower simulation error compared to the conventional discretization schemes. Moreover, also in the numerical simulation of the quasi-steady vortical flow, the simulation accuracy of the vortex-based scheme is superior to those of the conventional schemes.展开更多
文摘Aerodynamic design of convertible prop-rotor is a challenging and complex task.Instead of focus on a design condition,prop-rotor are requested to attain good performance in wide range of operating conditions.In present work,to further improve performance of prop-rotor under each operating condition,the concept of variable-pitch proprotor has been proposed.However,a compromising aerodynamic design of prop-rotor is inevitable,due to discrepancy of operating condition.Consequently,a multi-objective optimization is implemented with genetic algorithm.Factors which has significantly influenced on aerodynamic characteristics of prop-rotor are employed as design variable.To avoid expensively computational cost,two theories has been implemented and validated while it able to provide a promising result without high consuming of time.Eventually,several designed individuals within different performance has been analyzed and discussed.Subsequently a calculation of aerodynamic characteristic with highfidelity solver has been conducted as validation for designed individual.
文摘为了解决某电厂直吹式制粉系统阻力大、出力不足、制粉单耗高、分离器效率低、挡板调节性能差、煤粉细度不合格、磨损严重等问题,基于先进的旋涡理论,采用气固分离技术,对影响分离器性能的关键因素进行深入研究,设计出以旋风分离为主、惯性分离为辅的旋惯耦合粗粉分离器,并成功应用,同时对分离器出口煤粉输送管道进行优化改造。结果表明:该直吹式制粉系统优化改造后,分离器分离效率提高13.3%,制粉出力增加20%,制粉单耗下降4.73 k W·h/t。
文摘In this study, a new high-precision numerical simulation scheme for vortical flows (vortex-based scheme) is proposed. This scheme identifies a vortical flow in each computational cell, and then, reconstructs a vortical velocity distribution based on the Burgers vortex model. In addition, a pressure distribution in the vicinity of the vortex center is also reconstructed. The momentum transfer is calculated with the reconstructed velocity and pressure distributions, and therefore, the vortex-based scheme can simulate vortical flows more accurately than the conventional schemes. In fact, as the simulation result of inviscid vortex attenuation problem, the vortex-based scheme shows lower simulation error compared to the conventional discretization schemes. Moreover, also in the numerical simulation of the quasi-steady vortical flow, the simulation accuracy of the vortex-based scheme is superior to those of the conventional schemes.
