Throttle Opening Research Articles

Optimal proportional-integral speed control for closed-loop engine timing system

In internal combustion engines, adjusting the air-fuel ratio is essential to control the speed and minimize the burnt fuel. The throttle opening is the actuator to control the air-fuel. A better design for the used/conventional controller can give a better response without additional cost. In this work, the proposed controller gains of the proportional-integral (PI) controller are tuned to enhance the speed in constant and variable drive cycle modes. The tuning process is conducted based on two of the most efficient performance indices used in this field. The performance indices are integral absolute error (IAE) and integral time absolute error (ITAE). The optimization problem is solved using three reliable stochastic optimization algorithms to ensure mature convergence of the solutions, to avoid local optima solutions, and to ensure effective shrinking of the search space. The optimization algorithms are teaching-learning-based optimization (TLBO), particle swarm optimization (PSO), and genetic algorithm (GA). Different simulations are conducted to validate the results. The results are compared with conventional tuning methods regarding the system's time response.

Experimental evaluation of gasoline-hexane fuel blends usage in a spark ignition engine

In the present study, the influences of hexane addition to gasoline were researched on performance and exhaust emissions in a SI engine. It was aimed to increase engine performance and thermal efficiency of spark ignition engine. So, a single cylinder, four stroke SI engine was operated with gasoline and gasoline/hexane fuel volumetric mixtures (H10, H20, H30 and H40) at wide opening throttle (WOT) and 4000, 3600, 3200, 2800 and 2400 rpm. It was seen that engine torque and power output decreased while SFC increased with the addition of hexane in the fuel blends. Engine torque decreased by 5.69%, 7.66%, 10.80%, 14.86% with H10, H20, H30 and H40 compared to gasoline at 2800 rpm grespectively. Thermal efficiency declined by 3.27%, 7.50%, 8.95% and 11.12% using H10, H20, H30 and H40 test fuels compared to gasoline at 2800 rpm respectively. Higher CO and HC were measured with fuel blends according to gasoline for all test fuels. CO reduced by 3.77% with H40 compared to H10 at 3200 rpm. On the contrary, CO2 increased by 16.49% with H40 compared to H10 at 3600 rpm. HC increased by about 21.26% H40 compared to H10 at 3200 rpm. Although there is no positive difference on exhaust emissions and thermal efficiency is reduced, gasoline/hexane fuel mixtures can be used without modifications in SI engines.

Adaptive coordinated control strategy for improving shift quality under different operating conditions

In order to improve the shift quality of vehicles under different operating conditions (such as road resistance coefficient and throttle opening), this paper proposes an adaptive coordinated control strategy. This strategy utilizes a Forgetting Factor Recursive Least Squares (FFRLS) to achieve online identification of the road resistance coefficient. Based on the changes in throttle pedal opening and road resistance coefficient during the vehicle’s shifting process, the strategy adaptively adjusts the coordinated control parameter (fuel cut-off time) to achieve optimal control of vehicle shifting under different operating conditions. To evaluate the shift quality, shift jerk, friction work, torque peak, and shift time are used as performance indicators. Based on a constructed simulation model of the powertrain system, the influence of different operating conditions on the performance indicators is analyzed, and the effect of coordinated control parameters on improving shift quality under different operating conditions is compared. Corresponding fuzzy rules are then established to achieve adaptive adjustment of the coordinated control parameters through fuzzy control, ensuring effective improvement of shift quality for vehicles under different operating conditions.

V2X assisted co‐design of motion planning and control for connected automated vehicle

AbstractThe rapid development of vehicle‐to‐everything (V2X) communication technologies significantly promotes the revolution of intelligent transportation systems. V2X communication is expected to play a critical role in enhancing the safety and efficiency of connected and automated vehicles (CAVs), especially for mixed traffic scenarios. Additionally, the computational and storage capabilities of roadside units (RSUs) will be harnessed to effectively enhance the motion planning and control performance of CAVs within the constraints of limited on‐board computational resources. Thus, a V2X assisted co‐design of motion planning and control algorithm for CAVs to improve their situational awareness and computational efficiency is proposed. Under this architecture, a pre‐planning algorithm is proposed first to utilize the computational and storage capabilities of RSUs and generate feasible trajectories for different driving tasks. By analysing the relationship between driving risk index and motion planning performance, an online‐planning algorithm is derived to modify the pre‐planned trajectories in real‐time with static or dynamic obstacles. Furthermore, the lateral and longitudinal control of the vehicle using the Frenet coordinate system is decoupled. The lateral control employs an offline linear quadratic regulator (LQR) from RSUs to control the steering angle of the vehicle. The longitudinal control employs a dual‐loop PID to control the throttle opening of the vehicle. The performance of the proposed framework is evaluated and demonstrated by a Carsim‐Prescan simulation study in different mixed traffic scenarios. Compared with conventional methods, the proposed method improves the computational efficiency by 23% and reduces the collision rate by 13%.

Research on the influence mechanism of fluid control valve on the production of segmented horizontal wells and the balanced gas production control model: A case analysis of Sichuan basin natural gas

The existing research on the multiple fluid control valves to control the balanced exploitation of natural gas in horizontal wells lacks theoretical model support. On this basis, this paper established a flow rate and pressure model of the segmented horizontal well based on the fluid control valve. The model considers the throttling performance, installation position and opening adjustment step size of the fluid control valve for the first time. Next, systematically analyzed the mechanism of mutual influence of the opening and the position on the flow rate and pressure based on multiple fluid control valves. In addition, a novel method of using the dichotomy model to adjust the production of different production segments was proposed to analyze the horizontal wells of 15 production segments in Sichuan. It was found that when the opening adjustment step size is less than 5%, the natural gas production shows irregular changes, which makes it hard to effectively control the production of each segment. When the step size is 5%, the maximum production variation is 2.7%, which will have a more significant and meaningful effect on the exploitation of natural gas. Through seven iterations, the maximum production errors of high and low production segments are 1.3 % and 1.1 % respectively, both less than 2.7%. The research results verified the correctness of the theoretical model of segmented horizontal wells based on multiple fluid control valves. This research provided a theoretical basis for the opening control of multiple fluid control valves based on different production segments of horizontal wells.

The Effect of using an Ethanol blended fuel on Emissions in an SI Engine

The economic impact of limited fossil fuel resources plus the mandatory limit for carbon dioxide (CO2) emissions become important factors to developing alternative fuels for internal combustion engines. Ethanol (CH3CH2OH) blends are considered as alternative fuels due to their ability to reduce the greenhouse exhaust emissions. This study highlights the effects of unleaded gasoline (E0) and ethanol- unleaded gasoline blend E30 (with 30% volume of ethanol) on engine performance and exhaust emissions experimentally using a 1.4 litre four cylinder four stroke SI engine with a compression ratio of 9:1, for a variety of load and engine speed conditions.. The results indicate that the blend E30 slightly increases the engine’s torque and power after mid-engine speeds together with fuel consumption. However, exhaust emissions at 25% open throttle sees a reduction of carbon monoxide (CO), carbon dioxide (CO2) and hydrocarbons (HC) whilst nitrogen oxide (NOX) emissions increase at the lower speeds. At full throttle, E30 reduces the CO considerably whilst CO2 and NOX increase. Similar quantities of HC are produced.

Quantitative assessment of small-bore gasoline direct injection engine for homogenous stoichiometric lean condition with hydrogen addition in dual fuel mode

The global hunt for the sustainable fuel for the energy and transportation has reached the newer dimensions. The advancement in the engine technology makes the viable solution to fit the hydrogen as the working fuel for both CI and SI engines. The physio-chemical chemical properties of hydrogen have the apt fitment for the SI engine. With the advancement in the automotive electronics and precision control of the fuel handling system makes hydrogen a workable option for the replacement for the conventional fuels. In this research hydrogen was inducted into the intake manifold and Gasoline is injected directly into the cylinder of the small-bore Gasoline Direct Injection (GDI) Engine at wide open throttle condition. The intake manifold is slightly modified to accommodate the hydrogen induction system (0–8 Litres Per Minute), where premixed mixture of hydrogen and air is formed in the intake manifold; the equivalence ratio of 1.0, 1.02 and 1.08 was set for the given hydrogen induction. The engine conditions were set as 3000 rpm with five hydrogen addition fractions of 0 %, 1.5 %, 2.8 %, 4.2 % and 5.8 % respectively. The hydrogen induction improves the combustion rate and mean effective pressure; shorten the flame propagation, maximize the heat release rate and peak pressure attainment. Maximum of 16 % increase in the peak pressure is attained for the λ = 1 for the 5.8 % hydrogen addition fraction. On the emission side, consistent decrease in CO and HC emission; and increase of NO emission, since the mean gas temperature has increased.

Экспериментальные исследования изменения коэффициента избытка воздуха и свободного кислорода в отработавших газах бензинового ДВС

The operation of the internal combustion engine in areas of poor and rich mixture is characterized by a decrease in the efficiency of the catalytic converter and increase in the degree of wear of the system of elements fuel supply systems, ignition and antitoxic systems. Current trends of shifting the operation of the internal combustion engine to the area of poor mixtures. leads to increased emissions of NO and CO2, deterioration of the combustion process. The diagnostic parameters, which are free oxygen and the excess air coefficient, were theoretically determined and selected for the research. The regularity of the change in O2 at 20 % and 40 % of the throttle opening from the resistance of the exhaust tract and the spark plug gap with varying injection time duration has been established. Experimental control of the parameter l showed a trend of having a maximum in the zone of injection durations, and a gradual decrease when shifting to the zone of long injection durations to the limits of the efficiency of the internal combustion engine. An increase in the resistance of the exhaust tract leads to an equidistant shift of the characteristics l upwards into the zone of large values l while significantly reducing the range of the engine performance.

Experimental Research of the Effects of Benzoylthiourea Derivative Fuel and Gasoline Mixtures on Engine Performance and Emissions

In this study, the influences of Benzoylthiourea Derivative Fuel N-(2-amino-5-bromo-1,dihydropyridine-1-yl)carbonothioyl)-2-chlorobenzamide as an additive into gas-oline were researched on engine performance and exhaust emissions. For this reason, a single-cylinder four stroke gasoline engine was run at wide open throttle, and 2400, 2800, 3200, 3600 and 4000 rpm engine speeds. The changes of engine torque, power output, specific fuel consumption, thermal efficiency, CO, CO2 and HC emissions were experi-mentally investigated.

Test bench development and implementation for experimental determination of mechanical losses in single cylinder internal combustion engines

As mechanical efficiency has great relevance in the alternative engine performance, the authors research in the development of testing facilities to characterize the sources of engine mechanical losses. The present paper deals with the realization of a hardware platform to conduct experimental studies in small combustion engines to experimentally characterize the mechanical losses of a single-cylinder internal combustion engine by means of the indicated diagram and motoring methods. The system was completed by means of an electrical motor-generator coupled to a single-cylinder air-cooled spark ignition engine, a self-developed electronic hardware control, and a PC-based instrumentation and data acquisition system. Specifications of load-motoring-starting system, including the description of the proprietary electronic load regulation system, are detailed. Also, the instrumentation system of in-cylinder and intake pressures; Temperatures of intake air, exhaust gases, lubricant oil, and engine block; effective torque and crankshaft position are described, including the signal acquisition system. The methodologies for indicated diagram and motoring method are described, mentioning the required measurements to apply each method and the engine load-temperature considerations when an engine is tested in fired or motored conditions. The platform was used to study the mechanical losses of the engine under motored and fired conditions under a wide range of rotational speeds and throttle openings, allowing to draw conclusions about the operating features of the developed test bench in itself, and also about the mechanical losses of the engine tested. Initially, samples of cylinder pressure, torque, intake pressure as function of crank angle and indicate diagram were obtained, showing similar waveforms present in related literature. Then, variations of the aforementioned temperatures against rotation speed and throttle opening and results for the mechanical losses determined by indicated diagram and motoring methods are shown. Finally, two empirical correlations are proposed to estimate the mechanical losses. In the future the hardware platform will be utilized to investigate in-cylinder engine parameters, detailed thermal and mechanical engine performance

Stress-Based Lattice Structure Design for a Motorbike Application.

The "drive by wire" mechanism for managing the throttle is not applied to every modern motorcycle, but it is often managed through a steel wire. Here, there is a cam on the throttle control. Its shape allows the throttle opening to be faster or slower and its angle of rotation, required for full opening, to be greater or less. The maximum angle a rider's wrist can withstand depends on numerous musculoskeletal mobility factors, often limited by falls or surgery. Using a Progrip knob with interchangeable cams allows the customization of a special cam profile, to ensure the best engine response to throttle rotation and ergonomics for the rider. The use of FEA software and lattice structures, allows to realize a lightweight and efficient design, targeted for fabrication with additive manufacturing technologies. The cam was manufactured by exploiting MSLA technology. Finally, a dimensional inspection procedure was performed before assembly. The main result is to have obtained a lighter and cheaper component than the original. This study has allowed the design of a mechanical component consisting of innovative shape, light weight, and ergonomics. Furthermore, it demonstrates the effectiveness in the use of lattice structures to enable weight optimization of a component while minimizing the increase in its compliance.

Study on operation performance and application potential of the piston-type thermally-driven pump

To eliminate the high-quality energy consumption of the existing thermally-driven pump and then make it replace the mechanical pump, the piston-type thermally-driven pump with a similar structure to the linear compressor was proposed and studied in the paper. The coupling mechanism of working fluid flow and element dimension was analysed based on the force analysis of the piston assembly. In experimental data analysis, the variation of working fluid condition is used to determine the pump operation stroke. The experimental result shows variation tendencies of the vapor-phase fluid pressure and flow rate are greatly affected by its compressibility. The throttle valve has a major effect on the liquid-phase fluid pressure and flow rate besides the vapor-phase fluid flow rate. And the pump operation period decreases by 0.05 s ∼ 0.1 s as the vapor-phase fluid pressure and the throttle valve opening change under the testing condition. Meanwhile, the correlation mechanism of the action force, displacement and velocity of the piston assembly was analysed through a theoretical simulation. It can be discovered that the piston assembly velocity increases by 7.1 %∼12.6 % and the pump operation cycle decreases by 1.9 %∼6.8 % with increasing vapor-phase fluid pressure. In addition, the improvement direction of the pump structure was proposed based on a comparison between the experimental research and the theoretical analysis. Compared with the mechanical pump, the simulating result shows the thermally-driven pump can in theory reduce the relative power consumption by about 82 %. Finally, an alternative strategy was presented for substituting the mechanical pump with the piston-type thermally-driven pump in the absorption and ejector refrigeration systems, to verify its application potential in the industrial field.

Performance and emission characteristics of double split injection biodiesel engine with intake air throttling

Most diesel engines typically operate with high excess air in part load. Implementing air intake restriction with exhaust gas recirculation (EGR) could be a viable option for mitigating NOx emission and soot, particularly when utilizing biodiesel, attributing to biodiesel's inherent oxygen content. This study examines the effect of intake air throttle and EGR coupled with split injection strategies on a turbocharged 4-cylinder engine fuelled with B60-POME fuel. A parametric test was conducted to examine the impact of fuel injection pressure, intake air throttling and EGR, followed by Response Surface Methodology (RSM) optimisation. When EGR is implemented with a 45% intake throttle opening, a relatively low EGR rate of 5% is achieved. A study utilising RSM was conducted to optimise the control of air supply and split injection parameters, involved with a total of 6 control variables. The optimum parameter appears at a dwell angle of 12 °CA, SOI timing of −4°ATDC, 40% intake throttle opening, EGR of 6.75%, fuel injection pressure of 800 bar and split injection ratio of 50%. These settings yield prediction emission results that are closely similar to those obtained from the actual confirmation test.

Root cause analysis of flywheel gear failure in a marine diesel engine

Engine gear failures are of significant concern across a wide range of industries. It is important to investigate each gear failure in light of its unique loading and operating conditions for root cause analysis (RCA) and further corrective actions to avoid such failures in the future. The aim of this study was to investigate the premature failure of a flywheel gear of a marine diesel engine and establish the root cause and damage mechanisms using experimental and numerical analysis techniques. A bottom-up creative approach was adopted to assess the loading conditions on the failed gear by first estimating the bending deformation of the failed securing bolt, assuming overload torque on the flywheel caused an equivalent bending moment permanently bending the bolt. Von Mises equivalent stress acting on the gear was numerically estimated as σVM = 737 MPa, which was found significantly more than the specified yield strength of gear governing material AISI 1055 (σY = 550 MPa). SEM fractography revealed a quasi-cleavage failure mechanism in the ‘case’ region near the gear root and a ductile failure mechanism inside the ‘core’ region of the flywheel gear. A crack was found to initiate from the gear root consisting of high-stress concentration under overload stresses. RCA established that the flywheel gears had failed by overload stresses, caused due to overload torque generated from sudden inertial thrust in the internal combustion (IC) engine due to excess fuel throttle opening.

Experimental design of steel bearings and ceramic bearings to find efficient energy consumption

A bearing is a vital machine component that supports shafts, enabling smooth rotation and minimizing friction. The level of friction is determined by the coefficient of friction, which varies based on the bearing material. In this study, we evaluated two types of bearings: steel and ceramic, with the aim of identifying the one with the lowest frictional force and, consequently, the least input power required. To conduct a comprehensive comparison, we performed comparative tests on the Nogogeni Evo V vehicle, analyzing the energy consumption impact of both steel and ceramic bearings. The tests involved measuring the input power of each bearing type at various throttle openings, ranging from 10% to 100%. The results revealed that ceramic bearings exhibited superior energy efficiency compared to their steel counterparts. At all throttle openings, the ceramic bearings consistently demanded lower input power, indicating their higher efficiency. For instance, at 100% throttle opening, the input power for steel bearings was 17,939 watts, while ceramic bearings required only 17,290 watts, representing a 3.6% reduction. Moreover, ceramic bearings achieved higher rotation speeds, with the ceramic bearing rotating at 598 rpm, a 3.5% increase compared to the steel bearing's 577 rpm. Based on these findings, it can be concluded that the implementation of ceramic bearings would significantly enhance the energy efficiency of the Mobil Nogogeni Evo V electric motor. Therefore, for improved performance and reduced energy consumption, we recommend the incorporation of ceramic bearings in the vehicle's design.

Throttling Loss Energy-Regeneration System Based on Pressure Difference Pump Control for Electric Forklifts

At present, the hydraulic systems of electric forklifts and traditional internal combustion forklifts are mostly valve-controlled speed-regulation systems, which have large throttling losses and potential energy waste. To further improve the energy-saving ability of electric forklifts, the forklift’s common working conditions are analyzed in this paper. A throttling loss energy-regeneration system based on pressure difference pump control is designed, and the system’s working principle is described. Aiming to deal with the problem that the pump−valve compound speed regulation with constant pressure difference could not realize high controllability and energy saving at the same time, a control strategy for variable pressure difference pump−valve compound speed regulation based on pressure balance control is proposed. The handle signal is positively related to the target speed of the oil cylinder. In the low-speed stage, the closed-loop control of the actual output torque of the motor/generator keeps the pressure difference across the proportional throttle valve unchanged, and the speed adjustment is realized by changing the opening of the proportional throttle valve. In the high-speed stage, the valve opening area is kept unchanged and the target pressure difference is changed to achieve the target speed. Finally, the feasibility of the control strategy is verified through an AMESim simulation, and the minimum pressure difference switching point is determined through experiments. The experiments show that the system’s energy-saving efficiency can reach 21.5% under a 1 t load. With the increase in the load, the system’s energy-saving efficiency can be further improved.

Assessment of M15 Fuel on BS IV 2 and 3-Wheeler

Across the world, methanol is evolving as a clean, sustainable transportation fuel for the future. Methanol fuel is an alternative biofuel for internal combustion and other engines, either in combination with gasoline or independently. Methanol's high octane and oxygen content produces a cleaner burning gasoline which significantly reduces vehicle exhaust emissions. A lower boiling temperature for better fuel vaporization in cold engines, the highest H-C ratio for a lower carbon intensity fuel, and no Sulphur contamination which improves catalytic converter operation. In the paper, a study is carried out for the blend of 15% methanol (M15) with Gasoline on BS-IV vehicles and a comparison is done for the tailpipe emissions. A gap analysis of vehicles with E0 and M15 fuel is done with baseline emission testing along with full throttle performance of the vehicle to check the effect of oxygenated fuel (M15). The main purpose of this study is to analyze the impact of M-15 fuel on 2 and 3-wheeler vehicles in the as-is condition without any engine tuning and retaining the base gasoline (E0) settings.
 Keywords: M15 fuel, methanol, BS IV, blended fuel, tailpipe emission, hygroscopic, 2 and 3-wheelers, mass emission, fuel economy, NOx

Energy management of plug-in hybrid electric vehicles based on speed prediction fused driving intention and LIDAR

Driving intention and speed prediction are essential factors in the energy management of plug-in hybrid electric vehicles (PHEVs). This paper proposes an improved energy management strategy for the subject vehicle by speed prediction fused with driving intention and LIDAR data in a vehicle-following scenario. A driving intention recognition model is developed based on the gated recurrent unit (GRU), which takes the vehicle speed, throttle opening, and brake pedal force of the subject vehicle as input. Then integrating the LIDAR point cloud data and driving intention result of the subject vehicle to achieve more accurate speed prediction, where joint probabilistic data association and interacting multiple models methods are used to process LIDAR data. The more accurate speed prediction is then applied to design a prediction-informed adaptive equivalent consumption minimization strategy (PIA-ECMS) for real-time energy management optimization. Experimental results demonstrate the recognition accuracy of up to 88%, indicating that the driver’s driving intention can be identified effectively. The speed prediction has an error margin of no more than 5.9 km/h. Compared with existing adaptive ECMS without speed prediction, the proposed PIA-ECMS can enhance fuel economy by 1.3–2.7% while achieving better SOC charge sustainability.

Robust & nonlinear control of an ultra-supercritical coal fired once-through boiler-turbine unit in order to optimize the uncertain problem

The ultra-supercritical once-through boiler (OTB) unit is an advanced power generation technology with high plant efficiency and low emissions. However, it is difficult to realize a coordinate control for the ultra-supercritical OTB unit to achieve the fast and stable dynamic response during the load tracking and grid frequency disturbances and in the presence of unavoidable uncertainties. In this paper, an accurate grey box multivariable coupled nonlinear model of an ultra-supercritical boiler-turbine unit is considered. Steam pressure at throttle valve, specific enthalpy in separator and active power are adjusted at desired values by manipulation of the fuel rate command, feedwater rate command and throttle valve opening. In addition to the mentioned accurate model, limitations of operational parameters and uncertainty sources are considered in the controller design. This makes this research unique from previous works. According to affine nonlinear control theory, a nonlinear robust sliding mode controller is developed. Then using MATLAB μ - DK iteration syntax, a linear H-infinity (H∞) robust control is synthesized with selecting proper weight functions. This method is suitable for all types of power plants with a similar mathematical modeling approach. Simulations in MATLAB Simulink toolbox reveals that both designed controllers achieve appropriate performance in the presence of uncertainties and parameters’ limitations, but nonlinear controller has better performance. Finally, deficiencies of a linear controller with respect to the proposed designed robust controllers are denoted.

Numerical model of predicting surge boundaries in high-speed centrifugal compressors

A numerical model of the whole compression system is established in this paper. The introduction of the Laval nozzle and opening boundary methods adaptively simulate the physical fluctuating boundary conditions during the surge without any artificial hypothesis. Based on the model, the steady simulation method has the capacity to well predict the low-order systematical oscillations during the surge by monitoring flow parameters on several representative surfaces. The surge boundaries of a high-speed centrifugal compressor, including the mild surge and the deep surge, are predicted based on the current numerical model in different flow regimes. The discrepancies of the mild surge boundary between experimental data and numerical predictions are within 5% in the transonic regime, but within 0.5% in the subsonic and supersonic regimes. The sensitivities of the mild surge to the throttle opening degree differ much in different flow regimes: the highest is in the transonic regime and the lowest is in the supersonic regime. In the supersonic regime, there exist various mild surges in a wide range of throttle opening degrees and an unstable equilibrium point (UEP) which is the most typical characteristic of the two-regime surge. To the best knowledge of the authors, it is the first time that all the oscillation characteristics of various mild surges and the existence of UEP in the supersonic regime are well predicted by one numerical method.