JOURNAL OF THE ENERGY INSTITUTE

In this study, waste tyre was pyrolyzed at different conditions such as temperature, heating rate and inert purging gas (N-2) flow rate. Pyrolysis parameters were optimized. Optimum parameters were determined. The main objective of this study was to investigate combustion, performance and emissions of diesel and waste tyre oil fuel blend. Experimental investigation was performed in a single cylinder, direct injection, air cooled diesel engine at maximum engine torque speed of 2200 rpm and four different engine load including 3.75, 7.5, 11.25 and 15 Nm. The effects of waste tyre oil on combustion characteristics such as cylinder pressure, heat release rate, ignition delay (ID), combustion duration, engine performance were investigated. In-cylinder pressure and heat release rate increased with waste tyre oil fuel blend (W10) with the increase of engine load. In addition, ID was shortened with the increase of engine load for test fuels but it increased with the addition of waste tyre oil. Lower imep values were obtained because of the lower calorific value of waste tyre oil fuels. Maximum thermal efficiencies were determined as 28.27% and %25.12 with diesel and W10 respectively at 11.25 Nm engine load. When test results were examined, it was seen that waste tyre oil highly affected combustion characteristics, performance and emissions. (C) 2018 Energy Institute. Published by Elsevier Ltd. All rights reserved

lift profiles between gasoline and LPG fuels in a SI engine

In this study, a single-cylinder, four-stroke, single overhead camshaft (SOHC), spark ignition (SI) gasoline engine was converted to run with liquefied petroleum gas (LPG) fuel. To improve the volumetric efficiency, the camshaft of the engine was re-designed using classical spline method for different valve lifts. The variations of engine brake torque, power, brake specific fuel consumption (BSFC), HC, CO, CO2 and NOx emissions and exhaust gas temperature were investigated with unleaded gasoline and LPG fuels for different valve lifts. The experiments were conducted at 1700-3200 rpm engine speeds range at wide open throttle (WOT) and lambda = 1. Engine torque and power decreased and BSFC increased with LPG fuel for the 7 mm valve lift. Brake engine torque decreased by 8.82% and BSFC increased by 7.25% with LPG fuel compared to gasoline for 7 mm valve lift at 2600 rpm engine speed. However, HC and CO emissions decreased, NOx emissions increased with the usage of LPG fuel. HC and CO emissions decreased by 18.24% and 5.3%, respectively, and NOx emissions increased by 7.67%, with LPG fuel at 2600 rpm engine speed. An improvement was observed on engine torque, BSFC, HC and CO emissions with the increase of the valve lift to 8 mm and LPG fuel. At the low engine speeds, engine performance and exhaust emissions deteriorated with the increase of valve lift for gasoline fuel, while improvements were found at middle and higher engine speeds. (C) 2016 Elsevier Ltd. All rights reserved

The thought journal app: Designed to confront thoughts that influence sleep

Problems initiating or maintaining sleep are prevalent and impact the quality of life negatively. Negative thinking patterns may perpetuate insomnia by inducing a state of arousal and consequently disrupting sleep. 'Thought challenging' is a common strategy to adopt a positive and peaceful mindset, but requires high awareness to internalize rational reasoning. Regular self-report and feedback may support the acquisition of fundamental reflection skills. We developed a thought journal in a mobile app to facilitate thought challenging. With the app, the users can reflect on daily situations and get visualized summaries as feedback. We carried out one week trial to explore perceived benefit, motivation, user engagement, and its integration with a sleep support tool. The results showed that using the app improved self-reflection skills and visualized summaries are perceived as motivating to log thoughts

trapped residual gas via reduced valve lift

In this study, the effects of residual gas fraction (RGF) on homogeneous charged compression ignition (HCCI) combustion were investigated experimentally. Experiments were performed at different lambda values and constant intake air temperature of 80 degrees C with the blend of 20% n-heptane and 80% isooctane (PRF80) test fuel. In order to obtain exhaust gas trapping and HCCI operation, two different cam mechanisms, having reduced valve lift, were used. Valve lift values of 5.5 mm (In5.5) and 3.5 mm (In3.5) were used in cam mechanisms. Exhaust valve lift values were 3.5 mm (Ex3.5) for both cam mechanisms. The experimental findings showed that in-cylinder pressure and heat release rate decreased using In5.5-Ex3.5 cam mechanism compared to In3.5-Ex3.5. More residual gases were trapped using In3.5-Ex3.5 cam mechanism. Combustion was also retarded with low lift cams due to more trapped residual gases. Indicated thermal efficiency was found 28.4% with In 3.5-Ex 3.5 whereas obtained 33.57% with In 5.5-Ex 3.5 cam mechanism at 1000 rpm. RGF was computed as 20.12% and 21.12% with In 5.5-Ex 3.5 and In 3.5 Ex 3.5 cam mechanisms, respectively, at 1000 rpm engine speed and stoichiometric air/fuel ratio. Moreover, indicated thermal efficiency was found to be higher about 17.91% with In 5.5-Ex 3.5 according to In 3.5 Ex 3.5 at 1200 rpm. Consequently, it was observed that HCCI combustion phasing can be controlled using low lift cams. It was seen that trapping exhaust gases in the cylinder is a feasible and practical method to control combustion phasing and spread out the HCCI operating range. In addition, stable HCCI combustion can be achieved trapping exhaust gases resulting in avoiding knocking especially at high engine loads. (C) 2016 Elsevier Ltd. All rights reserved

Production of waste tyre oil and experimental investigation on combustion, engine performance and exhaust emissions

In this study, waste tyre was pyrolyzed at different conditions such as temperature, heating rate and inert purging gas (N2) flow rate. Pyrolysis parameters were optimized. Optimum parameters were determined. The main objective of this study was to investigate combustion, performance and emissions of diesel and waste tyre oil fuel blend. Experimental investigation was performed in a single cylinder, direct injection, air cooled diesel engine at maximum engine torque speed of 2200 rpm and four different engine load including 3.75, 7.5, 11.25 and 15 Nm. The effects of waste tyre oil on combustion characteristics such as cylinder pressure, heat release rate, ignition delay (ID), combustion duration, engine performance were investigated. In-cylinder pressure and heat release rate increased with waste tyre oil fuel blend (W10) with the increase of engine load. In addition, ID was shortened with the increase of engine load for test fuels but it increased with the addition of waste tyre oil. Lower imep values were obtained because of the lower calorific value of waste tyre oil fuels. Maximum thermal efficiencies were determined as 28.27% and %25.12 with diesel and W10 respectively at 11.25 Nm engine load. When test results were examined, it was seen that waste tyre oil highly affected combustion characteristics, performance and emissions. © 2018 Energy Institut