10 research outputs found
Effect of nanoclay on thermal behavior of jute reinforced composite
Due to enhanced mechanical strength, superior flame
resistance, and decreased gas permeability, montmorillonite
nanoclay has been introduced to the jute-polyester resin composite
materials for structural application. Long-fiber Bangla
tossa special jute is being used as reinforcement materials along
with 1, 3, and 5% addition of nanoclay within the matrix-fiber
mixture to find the optimum percentage of nanoclay. These
doped hand lay-up-processed plates are used to made samples
for dynamic mechanical analysis and thermogravimetry testing
as per ASTM standards. Temperature-induced weight loss due
to thermal decomposition was measured and char residue was calculated up to 1000 ยฐC, where 5% added nanoclay samples showed better thermal stability. Viscoelastic properties through storage modulus and loss modulus showed better stability with 1% nanoclay-added composite in dynamic mechanical analysis.Moisture and temperature did not affect the tested samples significantly
in diminutive exposure for 1% nanoclay-added samples
even though there is a loss of storage modulus 12 to 30%
for 3 and 5% nanoclay-added samples, respectively
Temperature effect and battery charging characteristics analysis based on charging C-rate
Developing fast charging proprieties for LiFePo4 battery is a key issue for a wider deployment of EV. The main drawback of LiFePo4 battery charging is overcharge, overcurrent and high temperature which affects longevity, efficiency, and battery life cycle. In this research, lithium iron phosphate (LiFePo4) battery is investigated for fast, and rapid charging with CC-CV principle. MATLAB/Simulink based custom-designed tool was developed. A dynamic model of lithium-ion phosphate battery is proposed in this research by considering the significant temperature and capacity fading effects. Results have shown that the LiFePo4 battery can be used for fast charging up to 100% and rapid charging up to 85% by maintaining the condition for lifespan of the battery and to shorten the charging time. The simulation results have been showed that, the constructed model can really represent the dynamic performance feature of the lithium-ion battery. The modified model can assess the efficiency of battery execution based on charging C-rate conditions. ยฉ BEIESP
Mechanical performance of montmorillonite dispersed jute reinforced composite
Surface treated jute accomplished by chemical treatments which enhanced the adhesion between polyester
resin and modified surface within the composite. Baking time for 6 hours also reduced the moisture content and
diminishes the hydrophilic properties of the corchorus olitorius jute fiber. Montmorillonite shell type nanoclay was
dispersed 1%, 3% and 5% within the jute fiber polyester matrix to enhance the mechanical performance. Effect of
temperature and high humidity were evaluated for this nanoclay filled composite through hydrothermal test for 15
days in the environmental chamber. Environmental degradation was not remarkable due to the exposure of the
temperature 80แดผC and 95% RH for this time period. Ductile properties like yield strength (YS), % of elongation were
calculated for two different stoke rate to understand the strain rate effect. 1% addition of nanoclay within the
composite shows the better performance in terms of yield, flexural and impact strength while 5% dispersed of
nanoclay does not have any beneficial effect within the composite due to the density and non-homogeneous mixture
of the clay. Fracture morphology by SEM/ FESEM revealed voids, broken fibers and nano particles within the matrix
Structural applications and emerging trends of nano- and biocomposites: a review
Composite materials are currently being used in applications for aerospace, leisure, construction, sport, packaging and automotive industries, especially for the last mentioned application.Yet, present day trends such as a rise in interest in environmentally-friendly materials and
the advancement of nanotechnology has led to the emergence of nano- and biocomposites. These materials offer comparable mechanical properties to conventional composites, with biocomposites having the added benefit of being biodegradable. This paper explores the nano- and biocomposites, focussing additionally on structural applications and emerging trends of this growing market
Mechanical Performance of Montmorillonite Dispersed Jute Reinforced Composite
Surface treated jute accomplished by chemical treatments which enhanced the adhesion between polyester resin and modified surface within the composite. Baking time for 6 hours also reduced the moisture content and diminishes the hydrophilic properties of the corchorus olitorius jute fiber. Montmorillonite shell type nanoclay was dispersed 1%, 3% and 5% within the jute fiber polyester matrix to enhance the mechanical performance. Effect of temperature and high humidity were evaluated for this nanoclay filled composite through hydrothermal test for 15 days in the environmental chamber. Environmental degradation was not remarkable due to the exposure of the temperature 80ยฐC and 95% RH for this time period. Ductile properties like yield strength (YS), % of elongation were calculated for two different stoke rate to understand the strain rate effect. 1% addition of nanoclay within the composite shows the better performance in terms of yield, flexural and impact strength while 5% dispersed of nanoclay does not have any beneficial effect within the composite due to the density and non-homogeneous mixture of the clay. Fracture morphology by SEM/ FESEM revealed voids, broken fibers and nano particles within the matrix
Crystallization kinetics and thermal behaviors of multi-walled carbon nanotube dispersed jute reinforced composite
Carbon nanotubes (CNTs) were dispersed within polyester resin to improve the thermal properties and to understand the degradation mechanism and reaction kinetics of jute reinforced composite. Viscoelastic behavior via dynamic mechanical analysis, strain rate effect and hygrothermal behavior of CNT filled jute composite were studied. The crystallization kinetics and microstructures were investigated with differential scanning calorimeter (DSC), X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Multiwalled CNT with 0, 1 and 3wt% was added within polyester resin matrix, whereas around 70% volume fraction of jute fiber is maintained in each sample. In dynamic mechanical analysis (DMA), 3% CNT filled composite showed better storage modulus and loss modulus values before the hygrothermal test. Due to the exposure to temperature (80ยฐC) and relative humidity (95% RH) for 15 days in environment chamber, both storage and loss modulus of this composite reduced by around 10%
Prediction of crack growth propagation of a super alloy through ANN modeling
Linear-elastic fracture mechanics based technique was used to measure the fracture toughness in terms of K1C of a solid solution super alloy. Due to thermal fatigue and high temperature exposure for various application of Alloy 617, it was demanded to measure crack growth behaviour of this alloy. Pre-cracked compact tension (CT) specimens ware used to determine the crack growth rate (CGR) of alloy 617 by direct current potential drop (DCPD) in-situ crack monitoring technique. Artificial Neural network (ANN) statistical model computed different fracture parameters from experimental inputs by feeding information to the network. This feed-forward network calculated the threshold fracture toughness, number of cycle to failure, slope of the Paris curve for the alloy at different temperatures and load ratios. The computational model correlates and converges with the experimental results with a maximum deviation of 6%. Thus, the model is recommended for complex and stochastic application of the nickel base super alloy 617
Mechanical Performance of Montmorillonite Dispersed Jute Reinforced Composite
Surface treated jute accomplished by chemical treatments which enhanced the adhesion between polyester resin and modified surface within the composite. Baking time for 6 hours also reduced the moisture content and diminishes the hydrophilic properties of the corchorus olitorius jute fiber. Montmorillonite shell type nanoclay was dispersed 1%, 3% and 5% within the jute fiber polyester matrix to enhance the mechanical performance. Effect of temperature and high humidity were evaluated for this nanoclay filled composite through hydrothermal test for 15 days in the environmental chamber. Environmental degradation was not remarkable due to the exposure of the temperature 80ยฐC and 95% RH for this time period. Ductile properties like yield strength (YS), % of elongation were calculated for two different stoke rate to understand the strain rate effect. 1% addition of nanoclay within the composite shows the better performance in terms of yield, flexural and impact strength while 5% dispersed of nanoclay does not have any beneficial effect within the composite due to the density and non-homogeneous mixture of the clay. Fracture morphology by SEM/ FESEM revealed voids, broken fibers and nano particles within the matrix
Thermal analysis of LiFePo4 batteries during rapid charge with evaporative cooling system
The development of rapid charging mechanism for LiFePo4 batteries
is one of the key concerns for electric vehicles. The main drawbacks of LiFePo4
battery charging are overcharge, overcurrent, and high temperature which
affects longevity, efficiency, and battery life cycle. The effect of the batteryโs
internal temperature on the rapid charging process has been investigated.
Firstly, the CC-CV charging method is applied for rapid charging to analyse the
internal temperature. Then, develop a thermal management system to enhance
the battery charging performances by maintaining the lowest level of raised
temperature. Experimental results have shown that the Refrigerant-134a based
cooling system is capable to maintain battery temperature within the range of
20ยฐCโ40ยฐC. Without any cooling system, the charging temperature is recorded
as 54.12ยฐC which is higher than the reference temperature. With the designed
cooling mechanism, the evaporator surface average temperature and battery
average temperature are measured as 14ยฐC and 25ยฐC, respectively
The Advancement of Solid-State Transformer Technology and Its Operation and Control with Power Grids: A Review
Solid-state transformer (SST) technology is one of the developing technologies that will be widely used in the future to integrate low-voltage and high-voltage networks with control circuitries and power electronics converters, facilitating renewables integration in smart grid applications. SST technology has crucial key advantageous features, including compact size and weight, low cost, and ease of connection in offshore applications. However, SST technology exhibits a few concerns, such as implementation, protection, economic, and communication compatibility, that need to be addressed. This paper aims to review SST technology with its advanced control schemes and provide future directions for research and development, applications, and prospects. In line with this, highly cited SST technology papers are examined to derive and summarize concerning issues related to its operation and control with further research development of power grids. Moreover, this review discusses the assessment and state-of-the-art technology of SSTs in different applications, focusing on configurations, control circuitry, and their drawbacks and benefits. Numerous issues and challenges of SST technology are explored to identify the existing knowledge gaps and potential future recommendations. All these critical analyses, information, and evaluations would benefit power engineers and researchers in developing and implementing advanced intelligent SST technologies for sustainable energy management in future power systems