Greenhouse gas (GHG) emissions released into the atmosphere cause climate change and air pollution. One of the main causes of GHG emissions is the transportation sector. The use of fossil fuels in internal combustion engine vehicles leads to the release of these harmful gases. For this reason, since 1992, several standards have been introduced to limit emissions from vehicles. Technologies such as reducing engine sizes, advanced compression-ignition or start/stop, and fuel cut-off have been developed to reduce fuel consumption and emissions. In this study, the contribution of deceleration fuel cut-off and start/stop technologies to fuel economy has been examined considering the New European Driving Cycle. Therefore, the fuel consumption values were calculated by creating a longitudinal vehicle model for a light commercial vehicle with a diesel engine. At the end of the study, by using the two strategies together, fuel economies of 17.5% in the urban driving cycle, 3.7% in the extra-urban cycle, and 10% in total were achieved. CO2 emissions decreased in parallel with fuel consumption, by 10.1% in total.

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Since 1997, the NEDC (New European Driving Cycle) has been used to measure CO2 emissions. However, because this cycle is unable to accurately replicate real-world driving conditions, a new procedure has been developed. The WLTP (Worldwide Harmonised Light Vehicles Test Procedure), which is 10 minutes longer and more dynamic than NEDC, has been used since late 2017. In this paper, fuel consumption, CO2 emissions, and energy demand of these two cycles are compared. The vehicle mathematical model was created in a MATLAB program using vehicle longitudinal motion equations for a light commercial vehicle with a diesel engine. The speed profiles of the commonly used NEDC and WLTP cycles were defined in the model, and the fuel consumption, CO2 emission values, and the total energy values required for each cycle were calculated. Furthermore, the recoverable energy potential of the cycle has been revealed. According to the WLTP cycle, the vehicle's fuel consumption and CO2 emission values were calculated at approximately 11% more than the NEDC cycle. The recoverable energy potential is 2.64 times higher in the WLTP cycle compared to the NEDC cycle. Thus, for vehicle designers, it is a very useful tool that can calculate the fuel and CO2 consumption of a vehicle in 100 km according to certain cycles, based on vehicle parameters.

Titanium and its alloys take attention, especially in aerospace, automotive, and biomedical applications because of their strength, corrosion resistance, and biocompatibility. Titanium components, in general, are produced by sheet metal forming. However, the springback effect is a critical problem in the forming process due to difficult formability of titanium sheets. In the present study, the hot forming process was applied to sheets to investigate the effect of deformation temperature on microstructure, mechanical properties, and springback behavior of commercially pure grade 2 titanium sheets. The springback angles were measured at the CAD model after the sheets were scanned by the 3D scanner. The tensile test, hardness measurements, and microstructural analysis were examined by using specimens that were cut from the sidewall and the bottom of the deformed sheet as U-profile. The results reveal that the microstructure is substantially changed, and the springback is reduced with increasing temperature; thus, optimum results were obtained compared to the data obtained at room temperature.

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