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The article presents results of research on commercially used cutting mechanisms of low-power (about 10 kW) wood size reduction machines driven by small engines. The energy consumed was determined based on work demand, showing that two-cylinder cutting mechanism consumes less energy than disc cutting mechanism and drum cutting mechanism when wood size reduction various species of wood, within the cross-section range from 10 × 10 mm to 50 × 50 mm. The main application of the tested machines is the reduction of branch volume when maintaining the infrastructure of urban green areas, in order to facilitate their transport. The average increase in energy consumption required for the size reduction of a single 2-m-long timber beam relative to the most energy-efficient mechanism (two-cylinder cutting mechanism) may range from 369% to 478%, while the average energy consumed during 1 h of continuous wood size reduction machines operation may increase relative to the least energy-efficient mechanism from 80% to 188%. The average productivity when reducing the size of the wood of the tested machines depending on the cutting mechanism ranges from 0.47 tons/h to 0.06 tons/h. The greatest productivity is characterized by the two-cylindrical mechanism cutting 0.88 tons/h.

Governments all over the world are setting policies and regulations that encourage companies to incorporate Battery Electric Vehicles (BEVs) as a part of their fleet and Canada is no exception. However, BEVs struggle to deliver on a wide variety of workload needs and ambient temperature changes tend to have a greater impact on their range. This study reviewed the impact of ambient temperature on BEVs and evaluated if such depressed vehicle battery capacity can deliver required vehicle work scope for the Canadian Nuclear Laboratories (CNL) Waste Management Areas (WMA). This study focused on three-years quantitative data of Light Duty Vehicles (LDVs) operated by CNL WMA. A Total Cost of Ownership (TCO) evaluation compared BEVs to representative WMA Internal Combustion Engine (ICE) vehicles. Findings indicate that WMA LDVs mileage needs are well within the capabilities of a 150 km capacity BEV. When ambient temperature changes to 0 °C and further to −15 °C, it impacts battery capacity, reducing the aforementioned 150 km capacity BEV by 53% and 40%, respectively. Comparatively, a 250 km capacity BEV would also not translate into meeting 100% of WMA vehicle work scope without recharging when temperature impacts are considered. TCO evaluation shows cost savings in implementing BEVs over WMA ICE LDV, with or without government rebates. There is potential for BEV technology to meet WMA Small Engine Vehicles (SEVs) i.e. all-terrain vehicles (ATVs) and Utility Task Vehicles (UTVs) mileage needs without modifications, contingent on ambient temperature above −15 °C.

The present research work is an attempt to develop a dedicated biogas fuelled SI engine technology from a 100 cc motor cycle. Such a small engine is coupled with alternator especially suitable in remote rural electrification which is still not connected to grid line or has a limited access. The experimental work presents the performance results of a small 98 cc, single-cylinder, four stroke cycle gasoline engine which is optimized to run on scrubbed biogas (CH4 93.8%) and raw biogas (CH4 56.6%) with successive modifications to the engine and its components. The work is carried out in stages to develop a dedicated biogas engine technology. The various aspects like piston crown geometry and compression ratio (CR), is investigated in this research work to evaluate the performances using biogas as fuel and comparing the same with gasoline is also made with the results obtained during experimental tests. The tests were conducted at 3000 rpm using three pistons having different crown geometries and cleavage on its crown. The selected three pistons enable to study the significance of CR (in the range of 6–9) and piston crown geometry to achieve the optimal configuration. The experimental results have revealed that increase in CR in a close range of 8:1 with larger cleavage on piston crown geometry enhances engine performance for Biogas fuelled small S.I. engine 100 cc category. It has been observed during comparative analysis that the maximum power produced by the biogas fuelled engine has improved by 13.4%, BSEC has increased by 23.30% and there is an 18.18% improvement in BSFC.

The internal combustion engine is the heart of cars, trucks, and many machines. It is the main source of movement and operation, and it consists of different mechanical sectors. Due to usage and aging, different faults can appear which affect engine operation and managing. Any small engine fault can turn into a major malfunction if it is not monitored and maintained at the proper time. Therefore, monitoring the performance of motors can save time and costs, improve their performance, and help them operate safely. Fault diagnosis, fault detection, and condition monitoring terms are used to describe similar concepts detection of any abnormality or deviation from the engines or machines normal condition. This paper describes a summary of the existing condition monitoring and fault detection techniques of the internal combustion engine, which are used for information collection to ensure operational safety, performance, reasonable maintenance, pollution prevention, and cost reduction.

The development and operation of road infrastructure requires machines and equipment driven by low-powered internal combustion engines. The authors of this paper examined five small spark-ignition engines. They used the most popular commercial design on the market, the Lifan GX 390, with a carburettor power system, and another commercial power unit with the most innovative power system, the Honda iGX 390, characterised by an electronically controlled carburettor flap. The remaining three tested constructions are proprietary solutions modernising the design of the Lifan GX 390 engine. The first is the application of an electronic injection and ignition system powered by gasoline, the second and third are systems powered by alternative fuels. Emissions tests were conducted under identical operating conditions on an engine dynamometer coinciding with European Union guidelines (Regulation 2016/1628/EU).The results of the tests showed that innovative solutions in most cases reduced CO,CO2, and HC emissions while increasing NOx compounds.

The in-cylinder flow characteristics of a four-stroke, four-valve, pent-roof small engine of motorcycle at engine speeds from 2000 rpm to 4000 rpm were studied using computational fluid dynamics (CFD). The aim of this study was to investigate the in-cylinder flow characteristics of small engines, including tumble, swirl, turbulent kinetic energy (TKE), angular momentum, in-cylinder air mass, turbulent velocity, turbulent length scale, and air flow pattern (in both intake and compression strokes) under motoring conditions. The engine geometry was created using SolidWorks, then was exported and analyzed using CONVERGE, a commercial CFD method. Grid independence analysis was carried out for this small engine and the turbulence model was observed using the renormalized group (RNG) k-ɛ model. The pressure boundary conditions were used to define the fluid pressure at the intake and exhaust of the port. The results showed that the increase in the engine speed caused the swirl flow in the small engine to be irregularly shaped. The swirl flow had a tendency to be stable and almost constant in the beginning of the compression stroke and increased at the end of compression stroke. However, the increase of in engine speed had no significant effect on the increase in tumble ratio, especially during the intake stroke. There was an increase in tumble ratio due to the increase in engine speed at the end of compression stroke, but only a marginal increase. The increase in engine speed had no significant effect on the increase in angular momentum, TKE, or turbulent velocity from the early intake stroke until the middle of the intake stroke. However, the angular momentum increased due to the increase in engine speed from the middle of the intake stroke to the end of compression stroke, and the angular momentum achieved the biggest increase when the engine speed rose from 3000 to 4000 rpm by 10 % at the end of the intake stroke. The increase in engine speed caused an increase of TKE and turbulent velocity from the middle of intake stroke until the end of compression stroke. Moreover, the biggest increase of TKE and turbulent velocity occurred when the engine speed rose from 3000 to 4000 rpm at the middle of intake stroke around 50 % and 25 %, respectively. Turbulent length scales appeared to be insensitive to increasing engine speed, especially in the intake stroke until 490 °CA. From that point, the value of the turbulent length scale increased as engine speed increased. The biggest increase in the turbulent length scales occurred when the intake valve was almost closed (around 20 %) and the engine speed was within two specific ranges (2000 to 3000 rpm and 3000 to 4000 rpm). Regarding the effect of engine speed, there were no significant effects upon the accumulated air mass in the small engine. The increase in engine speed caused an increase of turbulence in the combustion chamber during the late stages of the compression stroke. The increase in turbulence enhanced the mixing of air and fuel and made the mixture more homogeneous. Moreover, the increase in turbulence directly increased the flame propagation speed. Further research is recommended using a new design with several types of intake ports as well as combinations of different intake ports and some type of piston face, so that changes in air flow characteristics in small engines can be analyzed. Finally, this study is expected to help decrease the number of experiments necessary to obtain optimized systems in small engines.

The composition and size of the passenger car fleet is often influenced by legislation and policy, including taxation, scrappage, and vehicle registration policies. Numerous measures at national and international level have been investigated to reduce the air pollution and/or climate change impacts of passenger fleets. However, the objectives of climate change and air pollution policy occasionally are conflicting, and this has resulted in a number of well publicised policy shortcomings. This paper outlines the development of a fleet emissions control (FEC) framework which enables the dynamic and adaptive optimisation of fleet emissions through changes in taxation policy in Ireland. The data for analysis was obtained from national sources including datasets from the national emission inventory and COPERT model. Applications of regression-based modelling and statistical analysis were conducted to predict fleet, mileage, and emissions changes. The results of the FEC framework showed that no increase in NOx emissions, above 2007 levels, could be achieved at a cost of a small increase in CO2 in 2016 (+1.8%). This could be achieved by taxation policy primarily resulting in a shift away from small engine diesel vehicles (

The problem of maintaining the flat parameters of the working orbit of a small spacecraft using an electric thruster is considered. In low working orbits, due to the Earth’s atmosphere, aerodynamic forces act on the spacecraft, which cause a decrease in the radius of the orbit and the end of the target functioning. The analysis of the time parameters of the cyclogram for maintaining the working orbit of a small spacecraft with an electric jet engine is carried out taking into account the variability of the atmosphere density. The cyclogram consists of sections of passive movement and active movement under the action of a small engine thrust. For the satellite under study, the thrust parameters of the electric jet engine were selected, which allow the correction of the plane parameters of a low orbit. Using the characteristics of the thrust and specific impulse of an electric jet engine, we calculated the fuel reserves for correction over a long period of time. The results of the analysis show that it is effective to use an electric jet engine in terms of fuel consumption for correction.

This research investigates the use of biogas to run a spark ignition petrol engine and test for the engine performance. Conventional spark ignition petrol engine was modified into a dual fuel engine by changing the engine single fuel carburettor to dual fuel carburettor. The air orifice was closed by 50% to enable cooled start with natural biogas as the low calorific value won't facilitate combustion. The speed, torque, and other engine parameters where measured using a TD200 small engine test set (hydraulic brake dynamometer) interface and emissions of SO2, CO were measured using an emissions analyser. The torque, brake power was higher petrol by 39% than the biogas due to the lower calorific value of biogas. The exhaust temperature, SO2 and CO was 49% lower for the biogas than the petrol. The comparative analysis of the modified engine showed that petrol can be substituted partly with biogas and the engine used for varying applications because it offers window escape on the hydrocarbon reservoir depletion, green gases emission from the use of these petrol and landfill emission as well.

This study aims to analyze the effect of intake flow by various intake port designs on flow characteristics of small motorcycle engine cylinders by using simulation models. Geometry engine created using CAD software, then exported and analyzed using CONVERGE. The turbulence model is observed using a modified model (RNG) k-e. The pressure boundary conditions are used to determine the pressure fluid at the intake and exhaust port. The change of the intake port design based on the flow direction give effect to swirl ratio value. The helical intake port with same direction have the highest swirl ratio during intake and compression stroke. The largest increase occurred at the helical intake ports in the same direction in the middle of intake stroke by 383.33 % compared to the helical intake ports in the opposite direction. The change of the intake port based on the direction of flow do not have much effect on changes in air mass during the intake stroke. While the tangential intake port is bigger than the two helical intake ports around 3.5%. However, there was a slight change due to changes in the intake port on the accumulation of air mass during the compression stroke where in the two helical intake ports experienced a slight decrease in the incoming air mass. There is no significant effect with the change in the intake port model to this parameter especially at the beginning of the intake stroke up to 440 °CA, where the valve lift starts to be opened maximally. However, changes in turbulent kinematic viscosity occur after this point where the valve lift closes again where the highest value of increasing turbulent kinematic viscosity occurred at 585 °CA around 107.14 %, where the intake valve was almost closed. The changes of the intake port type affect the maximum value of the length scale peak where the intake port type of the helical model has a higher maximum value than the tangential type model. The highest value of increasing length scale occurred at 595 °CA around 40 %, where the intake valve was almost closed. Finally, it is concluding that the analysis carried in this work is useful in predicting the flow and in-turn optimizing combustion chamber of the engine.

This paper presents a study of residual gas, effective release energy and engine emissions of small engine with variable ignition timing at full load. The study was conducted by simulating the variable ignition timing from 10 to 40 degrees in the full-load operation mode at low speed (3000 rpm), medium speed (5000 rpm) and high speed (8000 rpm) of the engine, then comparing the changes of the residual gas, exhaust gas (NO x , CO, HC) and effective release energy. The results from the simulation showed that the ignition timing had a significant effect residual gas ratio, effective release energy, engine performance, and emission characteristic. When the engine speed at high speed and ignition timing is 10 °CA, the minimum residual gas ratio was 0.07%. At the ignition timing is 40 °CA, the maximum effective release energy was 0.87 kJ. Moreover, at the engine speed at low speed the maximum release energy was 0.635 kJ at 10 °CA of ignition, while the high speed achieved maximum release energy at 40 °CA was 0.848 kJ. The maximum engine brake torque was 20.37 Nm and the minimum BSFC was 334 g/kWh at medium speed and 30 °CA of ignition timing.

In this work, several methods for combined reactor modeling of carcinogenic polycyclic aromatic hydrocarbon (PAH) concentrations in aircraft combustion chambers for kerosene combustion were proposed and investigated. Settlement and experimental studies were carried out for a model combustion chamber of a small engine using three different combined approaches based on the results of three-dimensional CFD modeling. The first approach is to create a chain of sequential perfectly stirred reactors (PSR) and to replace individual combustion zones with reactors. The second approach uses ANSYS Fluent's automatically generated chemical reactor network (CRN). The third approach implements automatic generation of reactor chains according to a user-defined algorithm in the kinetic post-processor of the Chemkin Energico or KPPSMOKE program. We studied the atmospheric pressure combustion regime for liquid kerosene, with an air temperature behind the compressor of 423 K and an equivalence ratio of φ=0.22–0.33. PAH concentrations were determined experimentally by high performance liquid chromatography. As a result of the work, it was demonstrated that only the approach using kinetic post-processors shows the orders of PAH concentrations corresponding to the experimental ones.

Despite much research in aircraft engines, mainly before 1950s, very little has been done forsmall Internal Combustion (IC) engines. Small aircraft engines have specific requirements whencompared to larger IC engines due to size and non-linear scaling of significant characteristics. The engine - along with the air frame - is essential for trusted flight of aircraft, and needs to operate continuously between start-up and shut-down. Reduced reliability can lead to catastrophic failure.One critical aspect of IC engine operation is the multitude of variables and parameters (including environmental) and their variability in time (due to wear) which affect efficiency and reliability. Any engine will operate in very narrow combinations of variables and parameters This research is focused on setting an experimental protocol, selecting and collecting critical variables from data produced by a small aero engine. It then establishes dependencies for safe operation by developing computational models for the engine (Albin et al. 2012). The mathematical model developed in this article is based on real data (Vitale 1998), characterizes the engine under investigation and represents a platform for further computer analysis,simulations and optimization of engine. The developed model describes the operation of the engine at a point in its life and was validated in a number of separate experiments. Refereed/Peer-reviewed

Pollutant emission of vehicle cars is nowadays a fundamental aspect to take into account. In the last decays, the company have been forced to study new solutions, such as alternative fuel and learn burn mixture strategy, to reduce the vehicle's pollutants below the limits imposed by emission regulations. Pre-chamber ignition system presents potential reductions in emission levels and fuel consumption, operating with lean burn mixtures and alternative fuels. As alternative fuels, methane is considered one of the most interesting. It has wider flammable limits and better anti-knock properties than gasoline. Moreover, it is characterized by lower CO2 emissions. The aim of this work is to study the evolution of the plasma jets in a different in-cylinder conditions. The activity was carried out in a research optical small spark ignition engine equipped alternatively with standard ignition system and per-chamber. The engine runs at 2000 rpm at wide open throttle in standard ignition condition and slightly turbocharged in pre-chamber condition in order to overcome the decrease of compression ratio. In this activity methane and gasoline were used. Methane was always injected in the pre-chamber and ignited by spark plug; meanwhile gasoline was injected in the main chamber by port fuel injection mode. The combustion of the pre-chamber methane mixture generates four plasma jets that quickly ignite the mixture made with gasoline/air into the combustion chamber. In this condition the flame speed was much faster than the traditional ignition (gasoline injected in intake manifold without prechamber). Using optical data, significant information about the flame propagation in terms of the speeds and radius were obtained. The optical data were correlated with the engine performance and indicated measurements that showed an increase indicated mean effective pressure and coefficient of variation reduction when the pre-chamber was used. Furthermore the effect of pre-chamber ignition on the engine stability and efficiency in stoichiometric and lean-burn operation conditions was investigated.

This paper investigates the energetic advantage of the embedded propulsion compared to a state-of-the-art propulsion of an aircraft. Hereby, the integral method of boundary layer theory together with the potential theory is applied to analyze the boundary layer thickness and the impact of the flow acceleration due to the embedded propulsion. The aircraft body is treated as a flat plate and the engine as a momentum disk. For an embedded propulsion, there is a trade-off of the engine size, since the propulsion efficiency is affected by the boundary layer. On the one hand, the propulsion inlet momentum is noticeably reduced for a small engine size and the viscous friction is reduced due to boundary layer ingestion. On the other hand, a slow jet speed, i.e., a large engine size, increases the propulsion efficiency as known. The outcome of the energetic assessment is the following: the propulsion efficiency is increased and the drag of the aircraft body is reduced by the embedded propulsion compared to a conventional propulsion. The optimized aircraft engine size depending on Reynolds number is given as well as the dimensionless cost function.

The Whole-Day Driving Prediction (WDDP) concept is a unique plug-in hybrid electric vehicle (PHEV) control strategy that uses the day’s planned travels to determine if a small range-extending engine should be turned on at the start of each day. This control strategy allows for the use of a very small engine, in contrast to commercially available PHEVs, which generally have engines large enough to propel the vehicle. This paper presents modeling and simulation results for WDDP vehicles on the real-world logged driving cycles of 100 drivers who were each logged for between 2 and 6 weeks. The simulation results show that with an engine size between 5 and 7 kW, the WDDP vehicle with a 35-kWh battery has similar range capabilities to a pure EV with a 60-kWh battery. The consequence is that purchase price can be decreased while keeping similar range performance, encouraging a higher market penetration of plug-in vehicles. The results of this paper show that the WDDP concept is viable for real-world use, and has the potential to reduce plug-in vehicle costs while achieving driving ranges similar to the new long-range EVs recently introduced to the market.

In this paper, a novel application of a robust controller for an electronic governor of a small gas engine generator is presented. There are a few studies regarding the fluctuations in the concentration of bio-methane fuel and load fluctuation of a generator using an approximately 1-kW small gas engine generator. For a relatively small-scale local-production-type energy circulation system, such as the gas energy from a Tambo (GET) system, it is necessary to develop a small gas engine generator that can use the generated unpurified bio-methane gas to accommodate the load fluctuation. The GET system is a bio-methane gas production system, utilizing the sustainable resources from a paddy field, without requiring any distinct auxiliary facilities. We have examined the bio-methane gas produced from the GET system as the fuel of a small gas engine generator, which can supply electric energy and thermal energy to a greenhouse. We have studied the application of a robust engine controller by combining a model matching controller and an optimal observer (MM_OBSV controller) with the electronic governor of the small gas engine generator. The results indicate that the control system is adapted for the input disturbance (load fluctuation and modeling error), with the MM_OBSV controller embedded in the electronic governor of the small gas engine generator.

The purpose of this paper is to conduct an experimental research on the impact of mixing ratio of biodiesel from waste cooking oil and an innovative diesel fuel (in which a renewable component is contained) on the emissions of an up-to-date light and compact small engine that has a leading role in city cars and urban vehicles. Two blends’ mixing ratios (20% and 40% by volume) were tested and the results were compared to those obtained when the engine was operated with low sulfur diesel (ULSD) and ULSD blended with 15% by volume of renewable diesel. The results indicate that diesel+ enhances CO and HC emissions in the exhaust as regards ULSD. Blending diesel+ with WCO causes a further reduction for most of the engine operative field. Concerning particulate emission, accumulation mode dominates for all fuels. Diesel+ is always characterized by lower mean diameters as regards ULSD. The addition of WCO further reduces the court mean diameter. Particle number concentration obtained by fuelling the engine with B40 is the lowest as regards all the other tested fuels. Concerning NOx, a moderate increase of the emission was observed when fuelling the engine with diesel+, net or in blends.

The development of engine waste heat recovery technologies attracts ever increasing interests due to the rising strict policy requirements and environmental concerns. This paper presented the study of engine coolant and exhaust heat recovery using organic Rankine cycle (ORC). Eight working fluids were selected to evaluate and compare the performance of the integrated waste heat recovery system. Rather than the conventional engine ORC system mainly focusing on the utilization of exhaust energy, this work proposed to fully use the engine coolant energy by changing the designed parameters of the ORC system. The case study selected a small engine as the heat source to drive the ORC system using a scroll expander for power production. The evaluation results suggest that under the engine rated condition, the solution to fully recover the engine coolant energy can achieve a higher power generation performance than that of the conventional engine ORC system. The results suggest that adding a recuperator to the ORC system can potentially improve the system performance when the working fluids are dry and the overall dumped heat demand of the system can be reduced by 12% under optimal conditions. When the ORC evaporating and condensing temperature are respectively set at 85°C and 30°C, the integrated engine waste heat recovery system can improve the overall system efficiency by 9.3% with R600, R600a or n-Pentane as the working fluid.

A small diesel engine is a machine that has high efficiency but causes a high level of pollution. The most widely used fuel so far is fossil energy which is unrenewable energy. The fruit of the Calophyllum inophyllum plant has great potential to be developed as alternative energy for small diesel engines. In this study, the test fuel used was D100, B100, E5, E10, and E15. The small engine diesel used TG-R180 Diesel with a compression ratio of 20:1 at engine turns 1500, 1800, 2100, and 2400 rpm, and the braking load at a constant prony disc brake is 1,5 kg/cm2. The result of the study using E10 fuel can improve engine performance and can reduce the opacity of the exhaust gas. The highest power in the D100 fuel at 2100 rpm is 8,06 PS. The highest thermal efficiency of E10 fuel is 50,29%. The use of Calophyllum inophyllum biodiesel (B100) can reduce exhaust gas opacity in small diesel engines when compared to the use of D100. E10 fuel has the lowest exhaust gas opacity rate of 4,1%.

The main purpose of this work is to evaluate the possibilities of using the hydrogen as a clean fuel for the small horsepower engines. Due to the increasing spark ignition engine in the world, this caused deteriorating quality of air and due to the hydrogen combustion properties, which has a great effect on improving the performance of spark ignition engine. The engine was operated separately with each of Hydrogen or gasoline using a control valve, using the Ultrasonic-Hydrogen Electrolyzer System. In this article, all performance parameters of Ultrasonic-Hydrogen Electrolyzer System (UHES) were carried out such as the rate of hydrogen production and system efficiency under a different waveforms and wave frequency. The performance parameters of small horsepower gasoline single cylinder engine are carried such as the engine torque, engine revolution and power efficiency of an engine efficiency under the hydrogen gas-fuelled comparative with the pure gasoline-fuelled engine. The experimental results reveal that the triangular waveform has the maximum hydrogen production, UHES efficiency was 72 % and the hydrogen can be increased power efficiency up to 9-10% by using hydrogen without gasoline.

The paper presents the 1970s licensing agreement between the communist government of Poland and the Italian company Fiat for the production of small motor vehicles, the Fiat 126 model, and the consequent building of the Small Engine Car Factory ( Fabryka Samochodów Małolitrażowych) in Bielsko-Biała and Tychy. The project aimed to enhance Polish economic international competitiveness, to narrow a technological gap between the country and the West, but – most of all – to transplant to Poland an element of Western modernity: individual car ownership. In fact, with three million units produced, 126 was the car that had motorised Poland. The paper focuses on managerial problems that state bureaucracy had to tackle in the process of constructing a new car factory, showing how the political goal of mass motorisation overtook any other financial or industrial constraints, though reducing productivity and financial sustainability of the project.