The thesis has changed the heat and moisture exchange curves of Swiss Luwa air washer into double efficiency formulas which are widely used in our country with a computer, and also worked out the regression formula of...The thesis has changed the heat and moisture exchange curves of Swiss Luwa air washer into double efficiency formulas which are widely used in our country with a computer, and also worked out the regression formula of heat transfer efficiency(X). This has created favourable condition for us to use computer in our calculation of Luwa air washer.展开更多
Based on the analyses of the structural feature and the function requirements of newstyle bottle cap, the two fundamental components, the lining washer and the outer body, are abstracted as a plate and a cylinder with...Based on the analyses of the structural feature and the function requirements of newstyle bottle cap, the two fundamental components, the lining washer and the outer body, are abstracted as a plate and a cylinder with thin wall respectively. For simulating the deformation of the lining washer under equiaxial pressure, the modified Lagrangian finite element analysis is applied on the 228 triangular elements. Under assembly pressure, the plastoelastic deformation of both the lining washer and the outer body are studied in terms of Tresca＇s yield criterion and the limitation of the plastic deformation is presented when the two components are assembled into one unit. For the production of this kind of bottle cover, experiments are carried out by carefully measuring the changes of the diameter of lining washer as well as that of the outer body. It is shown that results from the experiments have a good agreement with the theoretical calculation and the maximum value of the allowable pressure has successfully been used in the design of newly developed bottle cap production system.展开更多
The main objective of this paper is to develop a simpleand efficient numerical model for estimation of heat and mass transfer between water spray drops and airstreamin horizontal parallel flow which enable us to accur...The main objective of this paper is to develop a simpleand efficient numerical model for estimation of heat and mass transfer between water spray drops and airstreamin horizontal parallel flow which enable us to accurateprediction of evaporative cooling performance.Thephysical process of a droplet evaporating in finite airflowhas been studied.Four basic differential equations havebeen developed with their numerical solutions providedby figures.展开更多
Air Washer are employed in large air-conditioning sys-tems for dust removal and for evaporative cooling withappropriate design which can result in energy saving.Topredict the heat and mass transfer in water spray-air-...Air Washer are employed in large air-conditioning sys-tems for dust removal and for evaporative cooling withappropriate design which can result in energy saving.Topredict the heat and mass transfer in water spray-air-flow system,a two-dimensional numerical model simu-lating the conservation of mass,momentum and energyof air and water are developed.Further,drop trajecto-ries in the case of horizontal parallel flow in air washerhave been simulated.The results of the simulations areused to investigate the effect of the initial droplet size,the spray angle and the airflow velocity on the drop ve-locity field and drop trajectories.展开更多
Numerical simulation method is applied in the study oftwo - phase flow dynamics in the eliminator of air wash-er. The carrier phase (air) is treated in Eulerian frame,the water droplets are tracked in the Lagrangian f...Numerical simulation method is applied in the study oftwo - phase flow dynamics in the eliminator of air wash-er. The carrier phase (air) is treated in Eulerian frame,the water droplets are tracked in the Lagrangian frame.A three - dimensional unsteady two - phase flow model isdeveloped. With the help of FLUENT software, air-stream velocity field and water droplets trajectories havebeen illustrated when their mixture passing through tra-ditional folded eliminator. The result of the simulationcan be used to investigate the mechanism of展开更多
On the bads of theory and experiment, this paper studies and analyses the factors such as water - air ratio, air velocity, spraying water pressure and initial water temperature, which affect the heat and mass transfer...On the bads of theory and experiment, this paper studies and analyses the factors such as water - air ratio, air velocity, spraying water pressure and initial water temperature, which affect the heat and mass transfer in air washer , thus can help us to reduce the power consumption and Improve the efficiency of heat and mass transfer.展开更多
The present work is focused on heat and mass transfer in a direct evaporative air cooler of one row counter flow spray. Models of the two-phase flow in such a air treatment system have been developed. The fields of te...The present work is focused on heat and mass transfer in a direct evaporative air cooler of one row counter flow spray. Models of the two-phase flow in such a air treatment system have been developed. The fields of temperature and relative humidity in spray chamber, as well as the trajectories of sprayed drops have been obtained by numerical method. Experiments aiming at quantifying the system performance and its influence factors have been conducted. It indicates that the increase of air velocity and water/air ratio while the decrease of nozzle density are favorable. The performance of the system of parallel flow spray and counter flow spray have been compared by means of humidifying efficiency. Comparison between numerical simulation and experimental results demonstrate good agreement for outlet air temperature with a maximum error of 8% observed for air relative humidity.展开更多
The main purpose of the present work is to make a further insight into the procedure of heat and mass transfer between water droplets sprayed and air stream in a direct evaporative air cooler used in air-conditioning ...The main purpose of the present work is to make a further insight into the procedure of heat and mass transfer between water droplets sprayed and air stream in a direct evaporative air cooler used in air-conditioning system in textile mills. The thermodynamic models of the two-phase flow in such a air treatment system have been developed for one row parallel flow spray.The fields of temperature and relative humidity in spraylchamber, as well as the trajectories of sprayed drops have been obtained by calculation. A series of experiment aiming at quantifying the system performance and its influence factors have been conducted. It indicates that the increases of air velocity and water/air ratio while the decrease of nozzle density are favorable. Finally, the comparison between numerical simulation and experimental results have been carried out. Good agreements have been found for outlet air temperaturewhile a maximum error of 10% has been observed for air relative humidity.展开更多
In this paper, we have made a study on the noise of ring spinning frame by analysing the noise radiating mechanism and the frequency spectrum of its main noise sources, such as the spindle system and the transmission ...In this paper, we have made a study on the noise of ring spinning frame by analysing the noise radiating mechanism and the frequency spectrum of its main noise sources, such as the spindle system and the transmission gear trains of the ring frame. Finally, three measures for reducing its noise are suggested: (1) using upper elastic bearing for the spindle structure, (2) using vibration isolating washers for the spindle support, and (3) improving the gear transmission structure design in the headstock of the frame.展开更多
The processes of heat and humidity transfer between air and water are what to be studied mainly in the paper, we put forward some main factors which influence the processes of heat and humidity transfer in the air was...The processes of heat and humidity transfer between air and water are what to be studied mainly in the paper, we put forward some main factors which influence the processes of heat and humidity transfer in the air washer. We come to the conclusion that we can change these main factors to achieve different heat and humidity transfer processes and decide processes of heat and humidity transfer of air and water with the initial temperature of spraying water in the air washer. All these results can make things convenient for the air conditioning management.展开更多
This paper summarizes the research results dealing with washer and nut taxonomy and knowledge base design, making the use of fuzzy methodology. In particular, the theory of fuzzy membership functions, similarity matri...This paper summarizes the research results dealing with washer and nut taxonomy and knowledge base design, making the use of fuzzy methodology. In particular, the theory of fuzzy membership functions, similarity matrices, and the operation of fuzzy inference play important roles.A realistic set of 25 washers and nuts are employed to conduct extensive experiments and simulations.The investigation includes a complete demonstration of engineering design. The results obtained from this feasibility study are very encouraging indeed because they represent the lower bound with respect to performance, namely correctrecognition rate, of what fuzzy methodology can do. This lower bound shows high recognition rate even with noisy input patterns, robustness in terms of noise tolerance, and simplicity in hardware implementation. Possible future works are suggested in the conclusion.展开更多
Since the automatic dishwasher became a very common household appliance,some negative surface modifications with dishes can happen.This paper is recapping main risk factors for glass and décor corrosion after lon...Since the automatic dishwasher became a very common household appliance,some negative surface modifications with dishes can happen.This paper is recapping main risk factors for glass and décor corrosion after long term washing in the dishwasher.The different possibilities for a detergent providing protection of glassware are pointed out.Additionally,the impacts on material care due to the US and EU-phosphate ban in dishwasher detergents are discussed.展开更多
文摘The thesis has changed the heat and moisture exchange curves of Swiss Luwa air washer into double efficiency formulas which are widely used in our country with a computer, and also worked out the regression formula of heat transfer efficiency(X). This has created favourable condition for us to use computer in our calculation of Luwa air washer.
基金This project is supported by Provincial Natural Science Fundation of Hei-longjiang, China (No.E0311) and Provincial Key Project of Heilingjiang,China (No.G99A13-1).
文摘Based on the analyses of the structural feature and the function requirements of newstyle bottle cap, the two fundamental components, the lining washer and the outer body, are abstracted as a plate and a cylinder with thin wall respectively. For simulating the deformation of the lining washer under equiaxial pressure, the modified Lagrangian finite element analysis is applied on the 228 triangular elements. Under assembly pressure, the plastoelastic deformation of both the lining washer and the outer body are studied in terms of Tresca＇s yield criterion and the limitation of the plastic deformation is presented when the two components are assembled into one unit. For the production of this kind of bottle cover, experiments are carried out by carefully measuring the changes of the diameter of lining washer as well as that of the outer body. It is shown that results from the experiments have a good agreement with the theoretical calculation and the maximum value of the allowable pressure has successfully been used in the design of newly developed bottle cap production system.
文摘The main objective of this paper is to develop a simpleand efficient numerical model for estimation of heat and mass transfer between water spray drops and airstreamin horizontal parallel flow which enable us to accurateprediction of evaporative cooling performance.Thephysical process of a droplet evaporating in finite airflowhas been studied.Four basic differential equations havebeen developed with their numerical solutions providedby figures.
文摘Air Washer are employed in large air-conditioning sys-tems for dust removal and for evaporative cooling withappropriate design which can result in energy saving.Topredict the heat and mass transfer in water spray-air-flow system,a two-dimensional numerical model simu-lating the conservation of mass,momentum and energyof air and water are developed.Further,drop trajecto-ries in the case of horizontal parallel flow in air washerhave been simulated.The results of the simulations areused to investigate the effect of the initial droplet size,the spray angle and the airflow velocity on the drop ve-locity field and drop trajectories.
基金Supported by Development Foundation of Dong Hua Univetsity
文摘Numerical simulation method is applied in the study oftwo - phase flow dynamics in the eliminator of air wash-er. The carrier phase (air) is treated in Eulerian frame,the water droplets are tracked in the Lagrangian frame.A three - dimensional unsteady two - phase flow model isdeveloped. With the help of FLUENT software, air-stream velocity field and water droplets trajectories havebeen illustrated when their mixture passing through tra-ditional folded eliminator. The result of the simulationcan be used to investigate the mechanism of
文摘On the bads of theory and experiment, this paper studies and analyses the factors such as water - air ratio, air velocity, spraying water pressure and initial water temperature, which affect the heat and mass transfer in air washer , thus can help us to reduce the power consumption and Improve the efficiency of heat and mass transfer.
文摘The present work is focused on heat and mass transfer in a direct evaporative air cooler of one row counter flow spray. Models of the two-phase flow in such a air treatment system have been developed. The fields of temperature and relative humidity in spray chamber, as well as the trajectories of sprayed drops have been obtained by numerical method. Experiments aiming at quantifying the system performance and its influence factors have been conducted. It indicates that the increase of air velocity and water/air ratio while the decrease of nozzle density are favorable. The performance of the system of parallel flow spray and counter flow spray have been compared by means of humidifying efficiency. Comparison between numerical simulation and experimental results demonstrate good agreement for outlet air temperature with a maximum error of 8% observed for air relative humidity.
文摘The main purpose of the present work is to make a further insight into the procedure of heat and mass transfer between water droplets sprayed and air stream in a direct evaporative air cooler used in air-conditioning system in textile mills. The thermodynamic models of the two-phase flow in such a air treatment system have been developed for one row parallel flow spray.The fields of temperature and relative humidity in spraylchamber, as well as the trajectories of sprayed drops have been obtained by calculation. A series of experiment aiming at quantifying the system performance and its influence factors have been conducted. It indicates that the increases of air velocity and water/air ratio while the decrease of nozzle density are favorable. Finally, the comparison between numerical simulation and experimental results have been carried out. Good agreements have been found for outlet air temperaturewhile a maximum error of 10% has been observed for air relative humidity.
文摘In this paper, we have made a study on the noise of ring spinning frame by analysing the noise radiating mechanism and the frequency spectrum of its main noise sources, such as the spindle system and the transmission gear trains of the ring frame. Finally, three measures for reducing its noise are suggested: (1) using upper elastic bearing for the spindle structure, (2) using vibration isolating washers for the spindle support, and (3) improving the gear transmission structure design in the headstock of the frame.
文摘The processes of heat and humidity transfer between air and water are what to be studied mainly in the paper, we put forward some main factors which influence the processes of heat and humidity transfer in the air washer. We come to the conclusion that we can change these main factors to achieve different heat and humidity transfer processes and decide processes of heat and humidity transfer of air and water with the initial temperature of spraying water in the air washer. All these results can make things convenient for the air conditioning management.
文摘This paper summarizes the research results dealing with washer and nut taxonomy and knowledge base design, making the use of fuzzy methodology. In particular, the theory of fuzzy membership functions, similarity matrices, and the operation of fuzzy inference play important roles.A realistic set of 25 washers and nuts are employed to conduct extensive experiments and simulations.The investigation includes a complete demonstration of engineering design. The results obtained from this feasibility study are very encouraging indeed because they represent the lower bound with respect to performance, namely correctrecognition rate, of what fuzzy methodology can do. This lower bound shows high recognition rate even with noisy input patterns, robustness in terms of noise tolerance, and simplicity in hardware implementation. Possible future works are suggested in the conclusion.
文摘Since the automatic dishwasher became a very common household appliance,some negative surface modifications with dishes can happen.This paper is recapping main risk factors for glass and décor corrosion after long term washing in the dishwasher.The different possibilities for a detergent providing protection of glassware are pointed out.Additionally,the impacts on material care due to the US and EU-phosphate ban in dishwasher detergents are discussed.
