In this paper, a model of the scheduling of machine tools in the flexiblemanufacturing line is presented by intensive analysis and research of the mathematical method oftraditional scheduling. The various factors corr...In this paper, a model of the scheduling of machine tools in the flexiblemanufacturing line is presented by intensive analysis and research of the mathematical method oftraditional scheduling. The various factors correlative with machine tools in the flexiblemanufacturing line are fully considered in this system. Aiming at this model, an intelligentdecision system based on rules and simulation technology integration is constructed by using the OOP( Object-Orented Programming) method, and the simulation experiment analysis is carried out. It isshown from the results that the model is better in practice.展开更多
A detailed experimental research on characteristics of the hydrodynamicpressure spreading in the base gap of the arch inverted plunge pool was carried out. The features ofthe distributon of its ampitudes and spectral ...A detailed experimental research on characteristics of the hydrodynamicpressure spreading in the base gap of the arch inverted plunge pool was carried out. The features ofthe distributon of its ampitudes and spectral density and its characteristics in time domain fortwo conditions, i. e. , (1) a through gap and (2) a blind gap were given. The influence of the dampat the joint opening upon the hydrodynamic pressure inside the gap was also investigated.Accordingly, the stabilization mechanism of the arch invert plunge pool was worked out.展开更多
This paper presents a numerical method for simulating the 2-D tidal flow andwater quality with the orthogonal curvilinear coordinates. In order to overcome the computationaldifficulties in natural rivers, such as the ...This paper presents a numerical method for simulating the 2-D tidal flow andwater quality with the orthogonal curvilinear coordinates. In order to overcome the computationaldifficulties in natural rivers, such as the complicated boundary figures, the great disparitybetween length and width of computational domain, etc. , orthogonal boundary-filled grid was used.The irregular domain in physical plane was transformed into a rectangular domain in a transformedplane, and the depth-averaged momentum equations and mass equation were given and discretized basedon the alternating direction implicit finite difference scheme in curvilinear coordinates. Theapplication of the presented method was illustrated by an example of analyzing the Yangtze River inthe vicinity of Nanjing city. A fair agreement between the measured data and computed resultsdemonstrates the validity of the developed method.展开更多
Aeration plays an important role in the treatment of activated sludge due tothe interactions among bubbles, sewage and activated sludge in an aeration tank. The aerationperformance is directly concerned with the effic...Aeration plays an important role in the treatment of activated sludge due tothe interactions among bubbles, sewage and activated sludge in an aeration tank. The aerationperformance is directly concerned with the efficiency of sewage disposal. So the three-dimensionaltwo-fluid model was established with emphasis on the phase interaction terms in this paper. Thismodel, as an extension of the two-phase flow model, involved the motion laws of three-phases, andwas compared with experimental studies. The finite volume method was used in the numericalsimulation of gas-liquid two-phase flow and gas-liquid-solid three-phase flow. In order to discussthe influence of gas-phase, liquid-phase and solid-phase motions in an aeration tank on the sewagedisposal, three kinds of boundary and initial conditions were adopted. The simulated results of theflow structure show qualitatively good agreement with the experimental data. And the theoreticalbasis for designing the best aeration tank was discussed according to the simulated results.展开更多
The two-dimensional plane water flow and water quality was developed by usingthe techniques of coordinate transformation, alternating directions, staggered grid, linearrecurrence, and implicit scheme in the study of l...The two-dimensional plane water flow and water quality was developed by usingthe techniques of coordinate transformation, alternating directions, staggered grid, linearrecurrence, and implicit scheme in the study of large water body in lakes. The model was proved tobe suitable for treating the irregular boundary and predicting quickly water flow and water quality.The application of the model to the Bosten Lake in Xinjiang Uygur Autonomous Region of China showsthat it is reasonable and practicable.展开更多
A three-dimensional numerical model was developed to simulate reaerationusing a body-fitted coordinate system. The model was designed to calculate the velocity and oxygenconcentration separately, called, 'no pairi...A three-dimensional numerical model was developed to simulate reaerationusing a body-fitted coordinate system. The model was designed to calculate the velocity and oxygenconcentration separately, called, 'no pairing resolution'. The velocity was calculated by SIMPLECalgorithm in the body-fitted coordinate system. The considerably proposed model was checked by areaeration experiment couducted in an open channel. The computed results agree considerably wellwith the experimental data. The model was also used to predict the reaeration in an S-shapedchannel, and the numerical results are discussed.展开更多
This paper is concerned with the research on the rational curve for thebucket of a spillway. A new type of rational curve against cavitation damage to spillway has beenproposed; and the numerical results show that the...This paper is concerned with the research on the rational curve for thebucket of a spillway. A new type of rational curve against cavitation damage to spillway has beenproposed; and the numerical results show that the proposed curve (gradually and continuously variedcurvature curve, abbreviated as GCVC curve) can greatly raise the minimum cavitation number andcause the distribution of water pressure on the curved surface more reasonable. The proposed curve(GCVC curve) is simple, and can be conveniently used in practical hydraulic engineering.展开更多
文摘In this paper, a model of the scheduling of machine tools in the flexiblemanufacturing line is presented by intensive analysis and research of the mathematical method oftraditional scheduling. The various factors correlative with machine tools in the flexiblemanufacturing line are fully considered in this system. Aiming at this model, an intelligentdecision system based on rules and simulation technology integration is constructed by using the OOP( Object-Orented Programming) method, and the simulation experiment analysis is carried out. It isshown from the results that the model is better in practice.
文摘A detailed experimental research on characteristics of the hydrodynamicpressure spreading in the base gap of the arch inverted plunge pool was carried out. The features ofthe distributon of its ampitudes and spectral density and its characteristics in time domain fortwo conditions, i. e. , (1) a through gap and (2) a blind gap were given. The influence of the dampat the joint opening upon the hydrodynamic pressure inside the gap was also investigated.Accordingly, the stabilization mechanism of the arch invert plunge pool was worked out.
文摘This paper presents a numerical method for simulating the 2-D tidal flow andwater quality with the orthogonal curvilinear coordinates. In order to overcome the computationaldifficulties in natural rivers, such as the complicated boundary figures, the great disparitybetween length and width of computational domain, etc. , orthogonal boundary-filled grid was used.The irregular domain in physical plane was transformed into a rectangular domain in a transformedplane, and the depth-averaged momentum equations and mass equation were given and discretized basedon the alternating direction implicit finite difference scheme in curvilinear coordinates. Theapplication of the presented method was illustrated by an example of analyzing the Yangtze River inthe vicinity of Nanjing city. A fair agreement between the measured data and computed resultsdemonstrates the validity of the developed method.
文摘Aeration plays an important role in the treatment of activated sludge due tothe interactions among bubbles, sewage and activated sludge in an aeration tank. The aerationperformance is directly concerned with the efficiency of sewage disposal. So the three-dimensionaltwo-fluid model was established with emphasis on the phase interaction terms in this paper. Thismodel, as an extension of the two-phase flow model, involved the motion laws of three-phases, andwas compared with experimental studies. The finite volume method was used in the numericalsimulation of gas-liquid two-phase flow and gas-liquid-solid three-phase flow. In order to discussthe influence of gas-phase, liquid-phase and solid-phase motions in an aeration tank on the sewagedisposal, three kinds of boundary and initial conditions were adopted. The simulated results of theflow structure show qualitatively good agreement with the experimental data. And the theoreticalbasis for designing the best aeration tank was discussed according to the simulated results.
文摘The two-dimensional plane water flow and water quality was developed by usingthe techniques of coordinate transformation, alternating directions, staggered grid, linearrecurrence, and implicit scheme in the study of large water body in lakes. The model was proved tobe suitable for treating the irregular boundary and predicting quickly water flow and water quality.The application of the model to the Bosten Lake in Xinjiang Uygur Autonomous Region of China showsthat it is reasonable and practicable.
文摘A three-dimensional numerical model was developed to simulate reaerationusing a body-fitted coordinate system. The model was designed to calculate the velocity and oxygenconcentration separately, called, 'no pairing resolution'. The velocity was calculated by SIMPLECalgorithm in the body-fitted coordinate system. The considerably proposed model was checked by areaeration experiment couducted in an open channel. The computed results agree considerably wellwith the experimental data. The model was also used to predict the reaeration in an S-shapedchannel, and the numerical results are discussed.
文摘This paper is concerned with the research on the rational curve for thebucket of a spillway. A new type of rational curve against cavitation damage to spillway has beenproposed; and the numerical results show that the proposed curve (gradually and continuously variedcurvature curve, abbreviated as GCVC curve) can greatly raise the minimum cavitation number andcause the distribution of water pressure on the curved surface more reasonable. The proposed curve(GCVC curve) is simple, and can be conveniently used in practical hydraulic engineering.
