Idle Speed Research Articles

Design of the MCCIS on the Gas-Fueled Motorcycle to Overcome Detonation in Engine Idling

Gasoline consumption is greater than fuel oil production in Indonesia. The situation has come to that of a fuel oil crisis. Prior research indicates that the exhaust gas emission of motorized vehicles using gasoline contains lead still as heavy metal. The problem with vehicles using fuel gas is that with the engine ignited and left idling detonation occurs because the gas supply is great while the air supply is small. In addition, the gas tank posible to explodes when sparks come from the combustion chamber. The objective of the research concerned here was to design the Mechanics Converter Considering Idle System (MCCIS) to overcome the problem of detonation at the time of engine idling, to design a flame arrester to prevent an exploding gas tank, and to testing the exhaust gas emission. The MCCIS may be used on low or high speed motorcycles using fuel gas. No detonation occurred in idle speed throughout. The flame arrester was able to avoid the sparks so the fire wasn't moving into the gas tank. Results of the exhaust gas emission tests indicate that exhaust gas emissions at idling, moderate and high speeds are included in the CO and HC content of the specified magnitude.

Research on Aging of the LNG Powered Ship Based on Computer Technology and Influence on Engine Performance

The ship’s LNG power system is a key part to ensure the normal operation of the ship. Every key part of the ship will be commanded by the LNG power system. In the part that this article focuses on, the main components of the marine engine LNG power technology are the LNG power ignition system, electronic fuel injection system and idle speed control system. The working principle of marine engine LNG power technology first controls the commands issued by the control system through internal sensors, converts the commands into electrical signals through the command input device and transmits them to various electronic control units. Then the control unit processes the signals and finally the actuator Turn each command from the LNG power unit into a specific control operation for the ship. LNG power technology has a huge impact on the entire shipbuilding industry, improving the performance and kinetic energy of ship engines, reducing ship energy consumption, reducing exhaust gas emissions and reducing pollution. This article studies them.

Effects of Ethanol–Diesel on the Combustion and Emissions from a Diesel Engine at a Low Idle Speed

In this study, detailed experiments were conducted on the combustion and exhaust characteristics of ethanol–diesel blended fuels. The four-stroke four-cylinder common-rail direct injection diesel engine was used. The experiment was carried out at 750 rpm at a low speed idle, and a 40 Nm engine load was applied to simulate the operation of the accessories during the low idle operation of the actual vehicles. The test fuels were four types of ethanol-blended fuel. The ethanol blending ratios were 0% (DE_0) for pure diesel, and 3% (DE_3), 5% (DE_5) and 10% (DE_10) for 3%, 5% and 10% ethanol mixtures (by vol.%). Blending ethanol with diesel fuel increased the maximum combustion pressure by up to 4.1% compared with that of pure diesel fuel, and the maximum heat release rate increased by 13.5%. The brake specific fuel consumption (BSFC) increased, up to 5.9%, as the ethanol blending ratio increased, while the brake thermal efficiency (BTE) for diesel-ethanol blended fuels remained low, and was maintained at 23.8%. The coefficient of variation (COV) of the indicated mean effective pressure (IMEP) was consistently lower than 1% when ethanol was blended. The blending of ethanol increased the ignition delay from a 12.0 degree crank angle (°CA) at DE_0 to 13.7 °CA at DE_10, and the combustion duration was reduced from 21.5 °CA at DE_0 to 20.8 °CA at DE_10. When ethanol blending was applied, nitrogen oxides (NOx) reduced to 93.5% of the level of pure diesel fuel, the soot opacity decreased from 5.3% to 3% at DE_0, and carbon monoxide increased (CO) by 27.4% at DE_10 compared with DE_0. The presence of hydrocarbon (HC) decreased to 50% of the level of pure diesel fuel, but increased with a further increase in the ethanol blending ratio. The mean size of the soot particulates was reduced by 26.7%, from 33.9 nm for pure diesel fuel, DE_0, to 24.8 nm for DE_10.

Modeling and controller design of a micro gas turbine for power generation

This paper investigates the modeling and controller design of a micro gas turbine in power generation scenario. From the perspective of the controller design, it is well recognized that an accurate model in possession of the complex dynamic characteristics of a micro gas turbine is paramount. Thus, a nominal nonlinear model originated from integrating the start-up model and the component characteristic map model together is established to depict the main operating modes of the full operation envelope, containing the start-up mode, loading mode and unloading mode. The start-up model is got by the combination of polynomial fitting method with identification method. The component characteristic map model is achieved by combining inter-component volume method with experiment data. The proposed nominal nonlinear model is realized in MATLAB/Simulink environment. Furthermore, nonlinear and linear active disturbance rejection controllers and a PID controller are designed respectively. Such controllers not only realize the speed tracking control from the idle speed to the nominal speed, but also achieve the load tracking control at the nominal speed by numerical simulations and hardware-in-the-loop tests. In addition, the nonlinear active disturbance rejection controller has the best control performance, which is validated through the simulation results and hardware-in-the-loop tests.

Effect of Injection Parameters on Vibration of High Pressure Common Rail Diesel Engine for Light Vehicle at Idle Speed

With the progress of science and technology and the improvement of people’s living standards, the comprehensive performance requirements of automobiles are also increasing. Reducing engine’s vibration and noise is one of the important research contents in the field of automobile research. An experimental study was performed to investigate the effect of injection parameters on engine’s vibration at idle speed by using a four-cylinder high pressure common rail diesel engine. On the premise of not changing the components, the influence of each parameter on the vibration is compared and analyzed by changing the parameters such as main injection timing, interval of pilot-main injection, pilot injection quantity and rail pressure. The test results show that the vibration of diesel engine can be reduced by delaying the main injection timing properly, and the optimal interval of pilot-main injection is related to the main injection moment and the quantity of fuel injection. The determination of the pilot injection quantity must be determined by the pilot-main injection moment and the cycle injection quantity together in order to achieve vibration reduction. The increase of rail pressure will increase the vibration of the whole machine. Thus, the proper injection strategy is conducive to improve engine vibration characteristics.

Research on Technical Characteristics of CDPF + SCR for China-III Heavy-Duty Diesel Vehicles Emission Retrofit Based on Remote Monitoring Method

In order to study the technology of reducing heavy-duty diesel vehicles PM and Nox emission, a China-III sprinkler driving on Tianjin expressway was selected to equip with CDPF+SCR for demonstration of PM and NOx emission retrofit. By using the remote monitoring method, the vehicle speed, engine speed, exhaust temperature and pressure drop of upstream and downstream CDPF, NOx concentration upstream and downstream SCR, geographical location and other data were collected and analyzed in real time, and analyze the characteristics of CDPF passive regeneration, SCR conversion efficiency and DPF matching with SCR. The results show that :the idling speed and the middle and low speed operating conditions of the sprinkler are evenly distributed, exhaust temperature at 175∼275 °C accounts for 74%, and CDPF started passive regenerative emission retrofit at 220°C, NOx concentration after installing SCR was mainly concentrated below 800ppm,the average NOx concentration was 620ppm, and the reduction rate of NOx concentration was 51.6%.

Influence of Bioethanol Blends on Performances of a Micro Turbojet Engine

This paper proposes a study regarding the use of bioethanol as fuel for turbine engines used in aviation. For this purpose, three blends of 5, 10, and 15% concentrations of bioethanol mixed with Jet A fuel were tested on JET CAT P80 microturbo engine. During the engine testing, the following parameters were monitored: engine speed, generated force, temperature in front of the turbine, fuel volumetric flow rate, and vibration levels measured both on axial and radial direction. The tests were performed by maintaining the microturbo engine for about 1 min at three operating regimes: idle, cruise, and maximum speed. In addition, a comparative analysis between fuels for a test with the microturbo engine from the idle position to maximum position is presented. After the tests were conducted, a jet engine cycle analysis was performed at the max regime and the fuel specific consumption, the efficiency of the combustion chamber, and the thermal efficiency of the engine for each fuel blend were calculated. The tests were made without making any modifications to the engine components or automation system.

Analysis of Fuel Injection Pressure Effect on Diesel Engine Combustion Opacity Value

The use of diesel engines for vehicle applications has expanded for decades. However, it produces black smoke in the form of particulate matter contains fine and invisible particles during operation. The popular method for measuring the smoke opacity is by using a smoke meter for its simplicity and less costly. Fuel injection pressure is one of the parameters that affect the emission significantly, and the proper nozzle adjustment can reduce the density of exhaust gases and improve the engine performance. The purpose of this study is to determine the optimum fuel spray pressure that produces the lowest opacity value and analyse the effect of fuel spray pressure on the opacity value at a different engine speed. The present experiment uses the Hyundai D4BB engine, and the pressure variations were implemented on the injector nozzle at 125, 130, and 135 kg/cm2. The engine was also tested with various engine idle speed, i.e., 1000, 1500, 2000, and 2500 rpm. It has been found that the optimum distance of fuel spraying is 147.679 mm with injector nozzle pressure 130 kg/cm2, and the value of opacity is 9.51%.

An experimental investigation of the impact of added HHO gas on automotive emissions under idle conditions

The paper describes an experiment aimed at specifying the effects of adding Brown's gas (HHO gas) in automotive engines operating at idle speed. HHO gas was obtained from the author's parallel plate generator with a single central anode and two side cathodes separated by six neutral plates. The generator was powered by an external power source (power supply unit) and produced a constant HHO gas flow rate in the experiment. The so obtained HHO gas was added to the engine intake systems of 5 passenger cars – three SI engines, i.e. Fiat Cinquecento, Renault Twingo, and Opel Corsa and two CI engines, i.e. Skoda Octavia and Opel Combo. The engines operated in idling conditions. The MAHA MGT5 analyzer measured the concentrations of CO, HC, NOx in the exhaust gases of those cars first fueled by stock fuel (SF) only and then with added HHO gas, i.e. SF + HHO. The ambient conditions remained constant.The results show that fueling with an HHO gas additive has an impact on emissions: CO and HC concentrations in the exhaust gases were reduced in the most of the cases; NOx concentration was reduced in the SI engines but increased in the Diesel ones. Adding HHO gas to the engine intake system of the Fiat Cinquecento operating at idle slightly deteriorated the combustion process there (the impact of carburetor-based supply without feedback). Although HC concentration was lower by 24%, the amount of CO increased by 34% and nitrogen oxides hardly changed. CO concentration if any decreased in the other vehicles.The concentration of HC in the exhaust gases of each of the vehicles show that adding HHO gas to the original fuel, regardless of fueling methods and techniques, reduces the concentration of unburned hydrocarbons: by more than 20% in the Fiat and by about 40% in the others. The NOx concentration in the exhaust gases of each of the vehicles show that after adding HHO to the original fuel, the amount of NOx depends on a fueling method. In the SI engines with indirect injection, adding HHO gas to the intake system reduced the NOx concentration. In the Fiat with a carburetor without feedback, the NOx concentration remained practically unchanged but it increased in the CI engines if HHO gas was added to their intake systems.

Ring Rolling speed rolls optimization to improve ring quality and reduce production time

In this paper, an analysis of the production time reduction as a function of the Idle and Axial rolls speed law in a Ring Rolling process was examined. Starting from an industrial case study, the authors defined a new milling curve able to produce a better ring quality with lower loads. From this result, the authors tested the effect of the production time reduction till the 40% of the initial one. The Ide roll velocity was varied in a range between 0.71 and 1.13 mm/s while the Axial roll between 0.35 and 1.70 mm/s. Geometrical and load parameters have been taken into account to compare the results achieved. The authors identified in the external ring diameter and in the Idle roll maximum load the most critical parameter to control; in particular, a break-even point was determined in order to select a set of rolls speed laws able to produce a good quality ring with lower production time (about 20%) and lower loads (about 10 %). In this research both experimental and numerical approaches were followed.

Diffusion charging measurements on exhaust solid particle number and lung deposited surface area of compressed natural gas and diesel buses.

Because of their direct contact with society, urban buses are prioritized targets for air quality improvement. In this study, a sample group of in-use urban old buses powered by compressed natural gas (CNG) and diesel engines was chosen for particle emission analysis. The CNG buses do not have any type of after-treatment, while diesel ones are equipped with a diesel particulate filter (DPF). To measure the lung deposited surface area (LDSA), a possible physical metric of exhaust particles' toxicity, a diffusion charger-based analyzer was utilized. The measurements were done at different engine speeds in stationary conditions. The results revealed that although the particle mass emission of CNG buses remains at a low level, the number of emitted particles for 75% of the CNG buses (depending on their maintenance conditions) is 10 to 100 times more than the retrofitted diesel ones, with the range of 106 to 107p/cm3. The rest 25% of the CNG buses were performing the same as the retrofitted diesel ones in terms of exhaust particle number in the range of 105p/cm3. In addition, the lowest LDSA parameter at low idle engine speed was measured to be 97.8 and 229.4μm2/cm3 for a CNG and a DPF retrofitted diesel bus, respectively. This result indicates the same and even lower LDSA and surface area and thus the lower possible toxic potentiality of exhaust particles of CNG buses compared to diesel vehicles at DPF downstream. Investigation on the different behavior of the CNG buses in the emission of particles showed the correlation of some aging parameters such as lubricant oil aging mileage with the released particles and the importance of periodic maintenance interval. Graphical abstract.

Improving Fuel Economy of Spark Ignition Engines Applying the Combined Method of Power Regulation

One of the disadvantages of spark ignition engines, whose power is regulated by throttling, is the increased fuel consumption at low loads and when the engine is idle. The combined method of engine power regulation by switching off the cylinder group and throttling working cylinders is one of the effective ways to improve fuel economy in the above-mentioned modes. This article presents the research results of the combined method of engine power regulation which can be realized by minor structural changes in operating conditions. The method implies the following: at low loads and at idle speed of the engine. Fuel supply to the group of cylinders is switched off with the simultaneous increase of the cyclic fuel supply in the working cylinders. The adequacy of the calculated results has been checked by the indication of operating processes in switched off and working cylinders. The research results of a six-cylinder spark ignition engine with the distributed gasoline injection using the combined power regulation system have been shown. The angles of opening the throttle which provides a non-shock transition from the operation with all cylinders to the operation with the cylinder group switched off have been determined.

Effect of geometric parameters on the performance of motorcycle catalytic converters

The critical environmental issues of the Indonesian automotive market growth are the increase in air pollution. Vehicle exhaust emission can cause significant problems for the human health and the environment. Therefore, vehicle emission control is indispensable to mitigate the environmental problem. One of the most widely used methods to reduce automotive emission is utilization of catalytic converter in exhaust system. In fact, the catalyst performance in the reduction of noxious gases depends on its material and geometric design. This study aims to evaluate the effect of geometric parameter on the performance of motorcycle catalytic converters. In this experimental study, the catalytic converter made of brass foil plate is mounted on motorcycle muffler. The effectiveness of three catalyst geometry models namely flat perforated plate, folded perforated plate and rolled brass sheet, will be evaluated in relation to the reduction of hydrocarbon (HC) and carbon monoxide (CO) content. HC and CO emission levels are measured by four gas analyzers. The results show that the geometric parameter has a significant effect on HC and CO’s composition in the exhaust gas. For idle speed test, the second geometry model of catalyst presents the best performance in reduction of Hydrocarbon and CO2 concentration.

Engine idle speed control using nonlinear multiparametric model predictive control

SummaryIn this article, a real‐time nonlinear model predictive idle speed controller based on multiparametric programming is designed for an SI engine. Idle speed is a crucial recurring condition in urban vehicles demanding proper control to avoid stall. As will be seen, the nonlinear model predictive control (NMPC) system designed, besides complying with the predefined constraints, demonstrates a far better performance than the prevalent industrial controllers and even conventional linear MPC controllers. More importantly, a new special structure combining offline nonlinear MPC and classical controller is employed to provide both robustness and fast response. Not only is the computational burden of the controller within that of the ordinary ECU controllers, it is also able to readily damp a disturbance of 20 N·m in less than 2.5 seconds and easily deal with parameter uncertainties. The control system also regulates engine gas pedal release, and converges to the set point with a settling time of less than 3 seconds and minimum fluctuations.

Determination of efficiency of condensation and heat teflification turbo units on the basis of turbine energy characteristics

In this work, the problem of calculating the efficiency of turbo-units of various types that are part of the equipment of electric and thermal energy sources was solved. In simplified approaches to the representation of turbine units, often used in algorithms of power system optimization programs, in order to reduce the estimated time, the dependence of the plant efficiency on the current power is ignored, the influence of the pressure in the steam extraction of cogeneration turbines to cover the heat load and the idle speed of the turbines are not taken into account. These approaches are easy to use and implement, however, they can introduce noticeable errors in the optimization results due to the lack of consideration of parameters and dependencies that occur in real equipment operation modes and significantly affect the amount of fuel used by the optimized system. In contrast to the simplified approach, energy characteristics were used in the work to determine the efficiency factors characterizing the efficiency of turbine units. This allows providing a more accurate assessment of the effectiveness in various operating modes without significantly complicating the algorithm with a slight increase in the estimated time. Using the proposed approach showed the presence of a noticeable refinement of efficiency compared to simple models and, therefore, the feasibility of representing turbine units using energy characteristics in program algorithms designed to optimize energy systems.

Research on a Multinode Joint Vibration Control Strategy for Controlling the Steering Wheel of a Commercial Vehicle

The vibration degree of a steering wheel has important reference significance for drivers to evaluate the ride comfort of the whole vehicle. To solve the jitter problem of the steering wheel of a commercial vehicle at idle speed, this work proposes a multinode joint vibration control strategy (MDVC) based on the associated vibration path of the steering wheel. Based on the analysis of the associated vibration transfer paths of the steering wheel, the whole vehicle was divided into a system comprising several nodes. For the decomposed node system, taking the vibration transmission path associated with the target as the research direction, the vibration reduction design of each node system is analyzed step by step. After exploring the possible causes of abnormal vibration of the steering wheel through experimental tests, the abnormal node structure interval was determined. By further extracting the structural model of the steering system from the vehicle, the hammering method was applied to test its modal and related frequency. Furthermore, an improved structure of steering support was also designed, and its fitting degree and modal characteristics were analyzed and compared to the original scheme. The following test results show that the structure improvement greatly reduces the vibration level of the steering wheel, meets the ideal design requirements of the steering wheel vibration reduction, and provides the possibility of weighing the correlation between these hierarchical node systems in whole vehicle.

Optimal design of discrete-time fractional-order PID controller for idle speed control of an IC engine

This paper aims at proposing a discrete-time fractional-order PID (FOPID) controller, which can stabilise the variation of the idle speed of an internal combustion engine due to the occurrence of the external load disturbance. The nonlinear idle speed dynamics is linearised to be approximated by a first order plus dead time (FOPDT) model so that the FOPID controller can be initialised by a Ziegler-Nichols type tuning rule. The initialised FOPID controller can stabilise the linearised model, but it may lose its control capability in nonlinear idle speed dynamics. Therefore, an optimisation problem is solved through genetic algorithm (GA) to minimise a cost function within a small region around the FOPID's initial parameters. The optimal discrete-time FOPID controller are compared to a conventional discrete-time PID controller. The simulation study reveals that the optimal discrete-time FOPID controller secures an excellent control performance to the nonlinear idle speed model.

Optimal design of discrete-time fractional-order PID controller for idle speed control of an IC engine

This paper aims at proposing a discrete-time fractional-order PID (FOPID) controller, which can stabilise the variation of the idle speed of an internal combustion engine due to the occurrence of the external load disturbance. The nonlinear idle speed dynamics is linearised to be approximated by a first order plus dead time (FOPDT) model so that the FOPID controller can be initialised by a Ziegler-Nichols type tuning rule. The initialised FOPID controller can stabilise the linearised model, but it may lose its control capability in nonlinear idle speed dynamics. Therefore, an optimisation problem is solved through genetic algorithm (GA) to minimise a cost function within a small region around the FOPID's initial parameters. The optimal discrete-time FOPID controller are compared to a conventional discrete-time PID controller. The simulation study reveals that the optimal discrete-time FOPID controller secures an excellent control performance to the nonlinear idle speed model.

Дослідження формування вібраційних ознак у осьовому напрямі на штатних ходових колесах вантажного візка мостового крана

The article discusses experimental studies of the formation of vibration accelerations in the axial direction on axles with driven and driven standard cylindrical double-flange travel wheels. The study of the formation of vibration signs was carried out during the movement of the cargo carriage of an overhead crane, both without load and with a load of various weights. Traveling wheels are the fastest wearing parts of an overhead crane. A decrease in the time of their operation leads to an increase in the monetary costs of repair work to restore the running wheels or replace them. Therefore, for modern crane construction, a very urgent task is to increase the service life of crane traveling wheels due to their modernization. The designs of crane traveling wheels are currently quite rigid and do not perceive distortions and shocks that arise when the rail track deviates from the recommended values. This leads to significant wear on the rails, as well as on the flanges of the crane traveling wheels. To check the previously obtained theoretical data, an experimental study was carried out on an overhead crane with a lifting capacity of 5 tons, a span of 22.5 m, a lifting height of 8 m, an operating mode of 7 K. drive standard running wheels of the overhead crane trolley. Also, the analysis of the regularity of the formation of vibration signs during the movement of the cargo trolley of an overhead crane at various speeds, as well as in its various operating modes, is carried out. The level of vibration accelerations in the axial direction on the axles of the wheels with an increase in the weight of the load demonstrates multidirectional tendencies. For the drive wheel, the RMS vibration is reduced compared to a smaller load case (30% between 0.5 tones and 2.0 tones), and approaches the value of vibration levels at idle speed.

A Switching System oriented Modeling and Control Strategy for Idle Speed Control of a Hybrid Powertrain

The market development of partially electrified powertrains in passenger cars motivates the re-consideration of the idle speed control problem. In this paper, a switching system model is first developed to unite the main discrete-event characteristics of the combustion engine and time-continuous characteristics of the electric motor. The presented model is classified as a discrete-time switching system model with linear subsystems.Based on this description, we further perform a model-based controller design using the lifting technique. Although the optimality property of the controller is bound to the assumption of constant turning speed, it still provides several useful properties. These are the inherent control allocation between electric and combustion engine, the consideration of the discontinuous behavior, and the discrete-time description basis which is important for implementation in a common controller architecture.