The threshing mixture of Cyperus esculentus(Tiger nut)planted in sandy areas is complex during harvesting,and there are problems of high impurity rate and high cleaning loss rate of the seeds.In this paper,the threshi...The threshing mixture of Cyperus esculentus(Tiger nut)planted in sandy areas is complex during harvesting,and there are problems of high impurity rate and high cleaning loss rate of the seeds.In this paper,the threshing mixture of Cyperus esculentus is taken as the research object,and the suspension speed of each component is measured to design an“airflow+vibration”sieving device.Use the vector polygon method to explore the law of motion of the vibrating sieve,establish the force model of the seeds on the sieve surface,and analyze the conditions for the seeds to penetrate the sieve.According to the principle of seeds penetrating the sieve and long stalks not penetrating the sieve,the geometric model of sieve blades opening degree adjustment mechanism is constructed.Study of the conditions under which long stalks can be thrown out of the machine.The experiment bench of the cleaning device was built,and the evaluation indexes were the rate of seed impurity and the rate of cleaning loss of the device,and the crank speed,sieve blades opening degree and fan speed were used as the experiment factors to study the influence law of each influencing factor on the evaluation index through single-factor experiment.Using response surface methodology to find the optimal combination of working parameters of the cleaning device.To verify the device’s application on the combine harvester to improve the effectiveness of the cleaning operation of the Cyperus esculentus combine harvester.展开更多
For intermediate water depths(typically ranging from 50 m to 80 m),designing steel catenary mooring systems for floating marine renewable energy(FMRE)platforms can be challenging due to the limited weight of suspended...For intermediate water depths(typically ranging from 50 m to 80 m),designing steel catenary mooring systems for floating marine renewable energy(FMRE)platforms can be challenging due to the limited weight of suspended mooring lines.This can substantially increase mooring line tensions following large platform offsets.In contrast,mooring systems using synthetic fibre ropes offer the potential to prevent large platform offsets while reducing peak mooring line tensions.In this study,novel semi-taut moor-ing systems incorporating polyester ropes and steel chains are proposed for a combined wind and wave energy system-the semi-submersible flap torus combination(STFC)concept,deployed at a 50 m wa-ter depth.The STFC integrates a semi-submersible floating offshore wind turbine(FOWT),a torus wave energy converter(WEC)and three flap-type WECs.The dynamic responses of the STFC with different semi-taut mooring configurations under operational and survival environmental conditions are assessed in terms of key performance parameters such as the platform’s motion responses and mooring line ten-sions.These performance parameters are compared against those of a chain-catenary mooring system.With the use of semi-taut mooring systems,significantly smaller mooring footprints as compared to the chain-catenary mooring systems can be achieved.Moreover,it is demonstrated that the semi-taut moor-ing systems are effective in reducing the maximum tension of the mooring lines.A basic cost analysis further indicates that semi-taut mooring systems offer substantial cost advantages over chain-catenary moorings in intermediate water depths.展开更多
基金supported by the Division City Science and Technology Achievement Transformation Guidance Plan Project(Development and demonstration of Cyperus esculentus harvesting machine in sandy areas of Xinjiang)(Grant No.KJ2023CG01)the Science and Technology Plan Project of the Corps-Science and Technology Talent Category:Analysis of Clogging Process of Roller Screen Holes in Cyperus esculentus Harvester and Research on Reverse Friction Declogging Methods(Grant No.2024DB016)the Science and Technology Research Program of Shihezi University:Development and Demonstration of High-Efficiency Harvesting Equipment for Cyperus esculentus Using Dual-Layer Differential Speed Roller Screens(Grant No.KJGG202404).
文摘The threshing mixture of Cyperus esculentus(Tiger nut)planted in sandy areas is complex during harvesting,and there are problems of high impurity rate and high cleaning loss rate of the seeds.In this paper,the threshing mixture of Cyperus esculentus is taken as the research object,and the suspension speed of each component is measured to design an“airflow+vibration”sieving device.Use the vector polygon method to explore the law of motion of the vibrating sieve,establish the force model of the seeds on the sieve surface,and analyze the conditions for the seeds to penetrate the sieve.According to the principle of seeds penetrating the sieve and long stalks not penetrating the sieve,the geometric model of sieve blades opening degree adjustment mechanism is constructed.Study of the conditions under which long stalks can be thrown out of the machine.The experiment bench of the cleaning device was built,and the evaluation indexes were the rate of seed impurity and the rate of cleaning loss of the device,and the crank speed,sieve blades opening degree and fan speed were used as the experiment factors to study the influence law of each influencing factor on the evaluation index through single-factor experiment.Using response surface methodology to find the optimal combination of working parameters of the cleaning device.To verify the device’s application on the combine harvester to improve the effectiveness of the cleaning operation of the Cyperus esculentus combine harvester.
文摘For intermediate water depths(typically ranging from 50 m to 80 m),designing steel catenary mooring systems for floating marine renewable energy(FMRE)platforms can be challenging due to the limited weight of suspended mooring lines.This can substantially increase mooring line tensions following large platform offsets.In contrast,mooring systems using synthetic fibre ropes offer the potential to prevent large platform offsets while reducing peak mooring line tensions.In this study,novel semi-taut moor-ing systems incorporating polyester ropes and steel chains are proposed for a combined wind and wave energy system-the semi-submersible flap torus combination(STFC)concept,deployed at a 50 m wa-ter depth.The STFC integrates a semi-submersible floating offshore wind turbine(FOWT),a torus wave energy converter(WEC)and three flap-type WECs.The dynamic responses of the STFC with different semi-taut mooring configurations under operational and survival environmental conditions are assessed in terms of key performance parameters such as the platform’s motion responses and mooring line ten-sions.These performance parameters are compared against those of a chain-catenary mooring system.With the use of semi-taut mooring systems,significantly smaller mooring footprints as compared to the chain-catenary mooring systems can be achieved.Moreover,it is demonstrated that the semi-taut moor-ing systems are effective in reducing the maximum tension of the mooring lines.A basic cost analysis further indicates that semi-taut mooring systems offer substantial cost advantages over chain-catenary moorings in intermediate water depths.
