A research project has been carried out at the National Technical University of Athens, Greece, to develop composite panels reinforced with cotton fibers. The primary aim of the project is to examine the mechanical pr...A research project has been carried out at the National Technical University of Athens, Greece, to develop composite panels reinforced with cotton fibers. The primary aim of the project is to examine the mechanical properties of such panels for use in secondary structural members such as wall or door systems. The use of natural fibers such as cotton, flax or sisal fibers has the primary advantage of being eco-friendly, low cost and low weight compared to glass fibers on the expense of lower structural properties. This paper presents results from experimental work on composite plates made from polyester resin reinforced with cotton fibers, with special attention given to the effect of the fiber type on the structural properties of the plates. The results from this study showed that the structural performance of cotton fiber composites is satisfactory for structural parts with low requirements, such as wall panels or doors. The present results for cotton fiber composites are also compared to testing results from previous studies on composites with flax/sisal fibers.展开更多
Drying characteristics,energy consumption and drying kinetics modeling of crashed cotton stalks dried in a microwave dryer were investigated in this research.A microwave dryer with an output power of 1000 W and 2450 M...Drying characteristics,energy consumption and drying kinetics modeling of crashed cotton stalks dried in a microwave dryer were investigated in this research.A microwave dryer with an output power of 1000 W and 2450 MHz was employed,and the effects of material load ranging from 50 g to 250 g on drying time,drying rate,drying efficiency and specific energy consumption were evaluated.The results showed that drying rate decreased with drying duration.A rising rate period was followed by a falling rate period and the overall drying process occurred in the falling rate period.Six mathematical models were used to fit the drying rates data of crashed cotton stalks,and Midilli et al.model was found the best prediction model by comparing R2,RMSE andχ^(2)values between experimental and predicted moisture ratios.With decrease in material load from 250 g to 50 g,effective moisture diffusivity increased from 2.8668×10^(-8)m^(2)/s to 7.9817×10^(-8)m^(2)/s.Results also indicated that drying efficiency and specific energy consumption significantly increased with the increase of the material load.Average drying efficiency and specific energy consumption varied in the range of 7.52%-19.78%and 12.49-35.90 MJ/kg water,respectively.There were a lowest energy consumption of 10.99 MJ/kg water and a highest drying efficiency of 17.13%at the material load level of 250 g.展开更多
文摘A research project has been carried out at the National Technical University of Athens, Greece, to develop composite panels reinforced with cotton fibers. The primary aim of the project is to examine the mechanical properties of such panels for use in secondary structural members such as wall or door systems. The use of natural fibers such as cotton, flax or sisal fibers has the primary advantage of being eco-friendly, low cost and low weight compared to glass fibers on the expense of lower structural properties. This paper presents results from experimental work on composite plates made from polyester resin reinforced with cotton fibers, with special attention given to the effect of the fiber type on the structural properties of the plates. The results from this study showed that the structural performance of cotton fiber composites is satisfactory for structural parts with low requirements, such as wall panels or doors. The present results for cotton fiber composites are also compared to testing results from previous studies on composites with flax/sisal fibers.
基金the Public Interest of Agricultural biomass characteristics and Sharing platform technology research(project number:201003063).
文摘Drying characteristics,energy consumption and drying kinetics modeling of crashed cotton stalks dried in a microwave dryer were investigated in this research.A microwave dryer with an output power of 1000 W and 2450 MHz was employed,and the effects of material load ranging from 50 g to 250 g on drying time,drying rate,drying efficiency and specific energy consumption were evaluated.The results showed that drying rate decreased with drying duration.A rising rate period was followed by a falling rate period and the overall drying process occurred in the falling rate period.Six mathematical models were used to fit the drying rates data of crashed cotton stalks,and Midilli et al.model was found the best prediction model by comparing R2,RMSE andχ^(2)values between experimental and predicted moisture ratios.With decrease in material load from 250 g to 50 g,effective moisture diffusivity increased from 2.8668×10^(-8)m^(2)/s to 7.9817×10^(-8)m^(2)/s.Results also indicated that drying efficiency and specific energy consumption significantly increased with the increase of the material load.Average drying efficiency and specific energy consumption varied in the range of 7.52%-19.78%and 12.49-35.90 MJ/kg water,respectively.There were a lowest energy consumption of 10.99 MJ/kg water and a highest drying efficiency of 17.13%at the material load level of 250 g.
