Signed direct graph (SDG) theory provides algorithms and methods that can be applied directly to chemical process modeling and analysis to validate simulation models, and is a basis for the development of a software e...Signed direct graph (SDG) theory provides algorithms and methods that can be applied directly to chemical process modeling and analysis to validate simulation models, and is a basis for the development of a software environment that can automate the validation activity. This paper is concentrated on the pretreatment of the model validation. We use the validation scenarios and standard sequences generated by well-established SDG model to validate the trends fitted from the simulation model. The results are helpful to find potential problems, assess possible bugs in the simulation model and solve the problem effectively. A case study on a simulation model of boiler is presented to demonstrate the effectiveness of this method.展开更多
The article reviews a brief literature on the modeling of hydrogen storage device for fuel cell. Different dimensional approaches in modeling hydrogen absorption/desorption in a metal hydride reactor for use in fuel c...The article reviews a brief literature on the modeling of hydrogen storage device for fuel cell. Different dimensional approaches in modeling hydrogen absorption/desorption in a metal hydride reactor for use in fuel cell are summarized. Mathematical modeling equations involved are also stated. The effect of various operating parameters such as temperature, concentration, viscosity, thermal conductivity and time on the gas is also verified. The importance of various simulation software with reference to their major functions is also identified. The review concludes on the opportunities and challenges with the use of hydrogen as an alternative renewable energy.展开更多
Cold stripping is the most common process for crude oil sweetening in oilfields particularly at offshore installations because of its low price and relatively easy operating conditions in comparison with other sweeten...Cold stripping is the most common process for crude oil sweetening in oilfields particularly at offshore installations because of its low price and relatively easy operating conditions in comparison with other sweetening processes. In this paper the cold stripping process in tray column has been modeled mathematically in static and dynamic modes, and solved with the MATLAB software. This process has been used in the existing treatment facilities of an offshore oil production complex for verifying the model results. With the help of HYSYS software the effective parameters on the process have been discussed and the optimized conditions finalized after some plant modifications for improving the performance of stripper columns have been proposed.展开更多
New alternatives and inventive renewable energy techniques which encompass both generation and power management solutions are fundamental for meeting remote residential energy supply and demand today, especially if th...New alternatives and inventive renewable energy techniques which encompass both generation and power management solutions are fundamental for meeting remote residential energy supply and demand today, especially if the grid is quasi-inexistent. Solar thermoelectric generators mounted on a dual-axis sun tracker can be a cost-effective alternative to photovoltaics for remote residential household power generation. A complete solar thermoelectric energy harvesting system is presented in this paper for energy delivery to remote residential areas in developing regions. To this end, the entire system was built, modeled, and then validated with the LTspice simulator software via the thermal-to-electrical analogy schemes. Valuable data in conjunction with a novel LTspice circuit were obtained, showing the achievability of analyzing transient heat transfer with the SPICE simulator; however a few of the problems to be solved remain at the practical level. Despite the unusual operation of the thermoelectric modules with the solar radiation, the simulation and measurements were in good agreement, thus validating the new modeling strategy.展开更多
文摘Signed direct graph (SDG) theory provides algorithms and methods that can be applied directly to chemical process modeling and analysis to validate simulation models, and is a basis for the development of a software environment that can automate the validation activity. This paper is concentrated on the pretreatment of the model validation. We use the validation scenarios and standard sequences generated by well-established SDG model to validate the trends fitted from the simulation model. The results are helpful to find potential problems, assess possible bugs in the simulation model and solve the problem effectively. A case study on a simulation model of boiler is presented to demonstrate the effectiveness of this method.
文摘The article reviews a brief literature on the modeling of hydrogen storage device for fuel cell. Different dimensional approaches in modeling hydrogen absorption/desorption in a metal hydride reactor for use in fuel cell are summarized. Mathematical modeling equations involved are also stated. The effect of various operating parameters such as temperature, concentration, viscosity, thermal conductivity and time on the gas is also verified. The importance of various simulation software with reference to their major functions is also identified. The review concludes on the opportunities and challenges with the use of hydrogen as an alternative renewable energy.
文摘Cold stripping is the most common process for crude oil sweetening in oilfields particularly at offshore installations because of its low price and relatively easy operating conditions in comparison with other sweetening processes. In this paper the cold stripping process in tray column has been modeled mathematically in static and dynamic modes, and solved with the MATLAB software. This process has been used in the existing treatment facilities of an offshore oil production complex for verifying the model results. With the help of HYSYS software the effective parameters on the process have been discussed and the optimized conditions finalized after some plant modifications for improving the performance of stripper columns have been proposed.
文摘New alternatives and inventive renewable energy techniques which encompass both generation and power management solutions are fundamental for meeting remote residential energy supply and demand today, especially if the grid is quasi-inexistent. Solar thermoelectric generators mounted on a dual-axis sun tracker can be a cost-effective alternative to photovoltaics for remote residential household power generation. A complete solar thermoelectric energy harvesting system is presented in this paper for energy delivery to remote residential areas in developing regions. To this end, the entire system was built, modeled, and then validated with the LTspice simulator software via the thermal-to-electrical analogy schemes. Valuable data in conjunction with a novel LTspice circuit were obtained, showing the achievability of analyzing transient heat transfer with the SPICE simulator; however a few of the problems to be solved remain at the practical level. Despite the unusual operation of the thermoelectric modules with the solar radiation, the simulation and measurements were in good agreement, thus validating the new modeling strategy.
