The aim of this study is to investigate the low velocity impact behavior of pre-stressed glass fiber/epoxy (GRP) nanocomposite tubes. During the production of filament wound tubes with a winding angle of ±55°, carbon nanotubes (CNT) were introduced to the epoxy resin at 0.5%wt and 1.0%wt by ultrasonic method. The nanocomposite tubes were pre-stressed to 32 bars internal pressure, one of the specified operating pressures according to ANSI/AWWA C950 standards. Low velocity impact tests were performed on the pure and CNT added pre-stressed GRP tubes at 5, 10 and 15 Joule energy levels. As a result of the experiments, the contact force-time, force-displacement graphs and absorbed energy values by the samples were obtained. In addition, the damage zones on the specimens were investigated. The effects of CNT reinforcements on the impact response and damage mechanisms of the specimens were evaluated. By adding CNT, it was observed that the damage areas of the samples decreased and was found to affect the impact response of nanocomposite tubes.

In this study, process parameters and mechanical properties of the multi-scale composite were investigated experimentally and predictably. Multi-scale material includes boron carbide particles and multi walled carbon nanotubes (MWCNTs) in the epoxy-based matrix. Both reinforcements were reinforced into the matrix with various rates simultaneously. Average three tensile strength and hardness values were determined. The tensile strength and hardness were enhanced thanks to high rate of B₄C usage up to 54.09% and 2.54%, respectively. The microstructure of the hybrid composite was investigated by Scanning Electron Microscopy. Also, Fourier Transform Infrared Spectroscopy was used to interpret spectral bands. The experimental data were analyzed using optimization method. Optimal process parameters for tensile strength and interfacial properties were determined. The Analysis of Variance (ANOVA) was used to obtain most significant factor and optimum levels of parameters. Finally, it was observed that B₄C ratio is the most dominant factor affecting the mechanical and thermal properties.

In this study, production and mechanical properties of the hybrid nanocomposite were investigated experimentally and estimated. Hybrid nanocomposites include boron carbide (B₄C) and multi walled carbon nanotube (CNT) in the epoxy resin. B₄C and CNT mixed into the epoxy with different percentages and produced. Tensile strength values of the produced samples was determined and compared. Thermal stability of the samples was analyzed by TGA. Samples are diversified by Taguchi method. The optimum sample was determined by comparison of the experimental and estimated results. Finally, the effects on each of the parameters were determined.

This study focused on the investigation of the effect of the SME-Jet A1 mixture on the thrust performance, fuel consumption and pollutant emissions of a small-scale jet engine, also the alternative of safflower methyl ester (SME) to Jet A1 fuel. The experiments were carried out by using bio jet fuels obtained by mixing Jet A1 and the fuel produced from safflower oil in taxi, approach, climb and take-off power cycles of a jet engine. The thrust forces of both types of fuel obtained from the percentage power values of the aircraft under real operating conditions were determined and accordingly CO, HC, CO2 emissions, fuel consumption and exhaust gas temperature measurements were made. As a result of the measurements, approximately 27.5% reduction in thrust was observed with the use of biojet. In addition, HC emissions decreased by up to 51%, while CO emissions increased by 30% at take off while being closer to each other at low rpm. While the CO2 emissions of methyl ester increased by 8-16% depending on the speed change, fuel consumption, while at an acceptable level at low rpm, exceeded 50% at take off.