This paper focuses on the development of an efficient semi-analytical solution of chatter stability in milling based on the spectral method for integral equations. The time-periodic dynamics of the milling process tak...This paper focuses on the development of an efficient semi-analytical solution of chatter stability in milling based on the spectral method for integral equations. The time-periodic dynamics of the milling process taking the regenerative effect into account is formulated as a delayed differential equation with time-periodic coefficients, and then reformulated as a form of integral equation. On the basis of one tooth period being divided into a series of subintervals, the barycentric Lagrange interpolation polynomials are employed to approximate the state term and the delay term in the integral equation, respectively, while the Gaussian quadrature method is utilized to approximate the integral tenn. Thereafter, the Floquet transition matrix within the tooth period is constructed to predict the chatter stability according to Floquet theory. Experimental-validated one-degree-of-freedom and two-degree-of-freedom milling examples are used to verify the proposed algorithm, and compared with existing algorithms, it has the advantages of high rate of convergence and high computational efficiency.展开更多
High-quality rice flour is the foundation for the production of various rice-based products.Milling is an essential step in obtaining rice flour,during which significant changes occur in the physicochemical and qualit...High-quality rice flour is the foundation for the production of various rice-based products.Milling is an essential step in obtaining rice flour,during which significant changes occur in the physicochemical and quality characteristics of the flour.Although rice flour obtained through mainstream wet milling methods exhibits superior quality,low production efficiency and wastewater discharge limit the development of the industry.Dry milling,on the other hand,conserves water resources,but adversely affects flour performance due to excessive heat generation.As an emerging powder-making technique,semi-dry milling offers a promising solution by enhancing flour quality and reducing environmental impact.This is achieved by minimizing soaking time through hot air treatment while reducing mechanical energy consumption to reach saturated water absorption levels.However,continuous production remains a challenge.This comprehensive review summarizes the effects of various milling technologies on rice flour properties and product qualities.It also discusses key control indicators and technical considerations for rice flour processing equipment and processes.展开更多
基金supported by the National Key Basic Research Program (Grant No. 2011CB706804)the Science & Technology Commission of Shanghai Municipality (Grant Nos. 09QH1401500 and 10JC1408000)
文摘This paper focuses on the development of an efficient semi-analytical solution of chatter stability in milling based on the spectral method for integral equations. The time-periodic dynamics of the milling process taking the regenerative effect into account is formulated as a delayed differential equation with time-periodic coefficients, and then reformulated as a form of integral equation. On the basis of one tooth period being divided into a series of subintervals, the barycentric Lagrange interpolation polynomials are employed to approximate the state term and the delay term in the integral equation, respectively, while the Gaussian quadrature method is utilized to approximate the integral tenn. Thereafter, the Floquet transition matrix within the tooth period is constructed to predict the chatter stability according to Floquet theory. Experimental-validated one-degree-of-freedom and two-degree-of-freedom milling examples are used to verify the proposed algorithm, and compared with existing algorithms, it has the advantages of high rate of convergence and high computational efficiency.
基金supported by the National Natural Science Foundation of China(Grant No.31972005)Xinjiang Uygur Autonomous Region‘Tianshan Talent’Training Plan Project,China(Grant No.2022TSYCCX0063).
文摘High-quality rice flour is the foundation for the production of various rice-based products.Milling is an essential step in obtaining rice flour,during which significant changes occur in the physicochemical and quality characteristics of the flour.Although rice flour obtained through mainstream wet milling methods exhibits superior quality,low production efficiency and wastewater discharge limit the development of the industry.Dry milling,on the other hand,conserves water resources,but adversely affects flour performance due to excessive heat generation.As an emerging powder-making technique,semi-dry milling offers a promising solution by enhancing flour quality and reducing environmental impact.This is achieved by minimizing soaking time through hot air treatment while reducing mechanical energy consumption to reach saturated water absorption levels.However,continuous production remains a challenge.This comprehensive review summarizes the effects of various milling technologies on rice flour properties and product qualities.It also discusses key control indicators and technical considerations for rice flour processing equipment and processes.