Wide Speed Range Research Articles

Analysis of the Research Status of Internal Combustion Engines

Since the internal combustion engine came out in the 1960s, it has become a relatively perfect machine through continuous improvement and development. Internal combustion engine has many advantages, such as thermal efficiency, high power, wide speed range, convenient matching and good mobility, so it has been widely used. All kinds of automobiles and tractors, agricultural machinery, engineering machinery and small mobile power stations in the world are powered by internal combustion engines. Ships, conventional submarines and some small aircraft are also propelled by internal combustion engines. The number of internal combustion engines in the world ranks first in the power machinery and plays a very important role in human activities. In the aspect of human technology, any successful invention can not be achieved overnight. The development of the internal combustion engine is the same. The internal combustion engine has gone through many stages of development and has been improved one after another. This paper mainly introduces the historical development of heat engines, and the improvement and use of different types of heat engines in the development.

Optimizing the Design of an Interior Permanent Magnet Synchronous Motor for Electric Vehicles with a Hybrid ABC-SVM Algorithm

This paper presents a comprehensive investigation of the optimal design of an interior permanent magnet synchronous motor (IPMSM) for electric vehicles (EVs), utilizing the hybrid artificial bee colony algorithm–support vector machine (HAS) algorithm. The performance of the drive motor is a crucial determinant of the overall vehicle performance, particularly in EVs that rely solely on a motor for propulsion. In this context, interior permanent magnet synchronous motors (IPMSMs) offer a compelling choice due to their high torque density, wide speed range, superior efficiency, and robustness. However, accurate analysis of the nonlinear characteristics of IPMSMs necessitates finite element analysis, which can be time-consuming. Therefore, research into methods for deriving an optimal model with minimal computation is of significant importance. The HAS is a powerful multimodal optimization technique that is capable of exploring several optimal solutions. It enhances the navigation capability by combining the artificial bee colony algorithm (ABC) with the kernel support vector machine (KSVM). Specifically, the algorithm improves the search ability by optimizing the movement of bees in each region generated by the KSVM. Furthermore, hybridization with the Nelder–Mead method ensures accurate and quick convergence at pointers discovered in the ABC. To demonstrate the effectiveness of the proposed algorithm, this study compared its performance with a conventional algorithm in two mathematical test functions, verifying its remarkable performance. Finally, the HAS algorithm was applied to the optimal design of the IPMSM for EVs. Overall, this paper provides a thorough investigation of the application of the HAS algorithm to the design of IPMSMs for electric vehicles, and its application is expected to benefit from the combination of machine-learning techniques with various other optimization algorithms.

The Effect of Impeller Tip Clearance on the Performance of a MGT Mixed Flow Compressor Stage Fitted with a Crossover Diffuser

Mixed flow compressor stage designs are becoming increasingly popular for use in Micro Gas Turbine (MGT) engines. Due to manufacturing constraints and structural considerations, such compressors typically feature unshrouded impeller designs. A numeric investigation of the effect of impeller-shroud tip clearance on the performance of a MGT mixed flow compressor stage fitted with a crossover diffuser is presented. Three baseline test compressors are designed using an in-house-developed application based on one-dimensional mean line theory. These cover a wide range of design mass flow rates, design speeds, and impeller meridional exit (mixed flow) angles. The performance of each of the test compressors are evaluated at an impeller-shroud tip clearance of 0.1 mm, 0.3 mm, and 0.6 mm. Commercial CFD software is used to verify the performance results of the various test compressor configurations. It is found that an increase in impeller tip clearance negatively impacts both compressor performance (total-to-total pressure ratio and efficiency) and choke margin. Conversely, stall margin increases with an increase in impeller tip clearance.

Comparison of REWS and LIDAR-based feedforward control for fatigue load mitigation in wind turbines

While optimizing wind energy harvesting has always been the principal goal of wind turbine control, extensive research has been conducted on the use of advanced control methodologies aiming to maximize the turbine’s power generation while also achieving secondary performance objectives, such as fatigue load minimization. Some recent studies have investigated the application of a classical control methodology known as exact output regulation for improved wind turbine control. This control method is designed to achieve the rejection of known input disturbances, while also ensuring the system output tracks a desired reference signal. These studies all assumed wind preview information from LIDAR measurements was available to support the controller design.In this paper we investigate the use of exact output regulation for turbine control, using wind speed estimates obtained from rotor speed measurements. Simulated performance comparisons conducted over a wide range of mean wind speeds show that the exact output regulation methodology using wind speed estimates derived from rotor measurements can deliver similar reductions in fatigue loads to those obtainable with LIDAR measurements, without compromising power generation.

Exploring the suppression mechanism of wind buffeting noise with bionic structures featuring leading-edge serrations and surface ridges

The aim of this study is to investigate the effectiveness and mechanism of wind buffeting noise suppression using a new bionic structure inspired by the quiet flight of owls. Firstly, the new bionic schemes based on NACA0012 wing with two sinusoidal leading-edge serrations and one straight leading-edge curve are used in a cavity after verifying the simulation. Then, the results of the three bionic schemes are compared and analyzed. It is found that the schemes with leading-edge serrations and surface ridges can suppress wind buffeting noise effectively. In particular, the sinusoidal scheme with a wavelength λ = 0.24 c (chord length c) can significantly reduce resonance energies above 21 dB over a wide range of speeds. Furthermore, the study reveals that in the bionic scheme, only the negative pressure core moves in the opening and hits the trailing edge, which reduces the pressure fluctuation in the cavity. The boundary layer thickness (BLT) also fluctuates in span under the influence of the leading-edge serration and the surface ridge, which is favorable for suppressing wind buffeting noise. However, the suppression effect is not solely related to the fluctuation of BLT in the span at the trailing edge but is also influenced by the minimum BLT at this point. Therefore, if the BLT has a certain intensity fluctuation in the span, and the minimum BLT at the trailing edge is close to that of the smooth airfoil scheme, the noise suppression effect is significant.

Моделирование режима электрического торможения тепловоза с последовательным возбуждением коллекторных тяговых двигателей при использовании силового полупроводникового преобразователя

Purpose: To consider the structure, advantages and operating principle of a new transistor converter based on isolated gate bipolar transistors (IGBT) for diesel locomotives with commutator traction motors in the electric braking mode, as well as the implementation features of this mode on diesel locomotives. To show the functional structure of the converter automatic control system for the electric braking mode. To plot a potential braking characteristic of a diesel locomotive with a new converter. Methods: Simulation modeling of the electric braking mode using a computational mathematical model of a traction drive in the Matlab Simulink environment. Analysis of the simulation results of the traction drive operation in stationary and dynamic conditions. Comparison of the obtained braking characteristic with the existing one for 2TE25KM diesel locomotive. Results: It is established that the use of the proposed transistor traction converter in the power electrical circuit of a diesel locomotive provides axis-by-axis control of a commutator traction electric drive in the electric braking mode with series excitation of traction motors and allows to significantly increase the electric brake efficiency at low speeds. The proposed solution implements the target braking force of the locomotive in a wide range of speeds, as well as its limitations due to the electromechanical parameters of the diesel locomotive assemblies. Practical significance: It is shown that the proposed solution provides the increase of the electric brake efficiency, life extension of brake shoes and wheels of the rolling stock.

Experimental Investigation of Different Extraction Methods for Producing Biofuel from Jatropha Seeds and Castor Seeds

While energy production is highly dependent on fossil fuels, which consider the main source of global warming, biofuels would play a significant impact in diminishing such warming. In this paper, biooils were extracted from inedible seeds (Jatropha and Castor) using different continuous devices (solvents, screw presses, and hydraulic press-machines), aiming to achieve the highest oil’s yield of improved extraction properties at reduced time and energy. A wide range of engine speeds of 35, 60, 85, 110, and 135 rpm and preheating temperatures of 100, 125, 150, 175, 200, and 250°C were extensively studied to find their impact on the extraction properties. Results proved the ability of the screw press machine to extract the highest biooil yields from Jatropha and castor seeds. The optimum yield of Jatropha and castor were achieved at an extraction temperature range of 150-175°C at a motor speed of 135 rpm and a temperature range of 200-250°C at a motor speed of 35 rpm, respectively. Noteworthy, the yield of extracted castor oil is potentially solidified at low temperatures <100°C, leading oil samples to become like a dough. In contrast, lowering the temperatures of the Jatropha seeds improved the physical and chemical properties of the extracted oil. At a certain temperature (e.g., 100°C), the properties of both extracted and diesel oils are quite similar, which can be used directly in diesel engines.

Experimental investigation and analysis of proposed hybrid vertical axis wind turbine design

In this research, an experimental and computational analysis of a novel hybrid vertical axis wind turbine (VAWT) arrangement has been performed. We suggest an innovative VAWT design that has a high power coefficient and self-starting capability. The inner side of the proposed hybrid system has been integrated with the H-rotor turbine with cambered blades, which demonstrates strong self-starting capabilities at various azimuths. Three NACA0018 airfoil blades are mounted on the outside of the proposed hybrid wind turbine, while three DU 06-W-200 airfoil blades are installed on the inside. Based on a similarity analysis, a scaled-down model was developed, and performance characteristics such as the output power, power coefficient ([Formula: see text]), dynamic torque coefficient ([Formula: see text]), and static torque coefficient ([Formula: see text]) were determined. An existing hybrid VAWT and a typical H-rotor Darrieus design were also examined for comparison. The highest [Formula: see text] for the proposed hybrid design was found to be 0.486 at a tip speed ratio (TSR) of 3, while the H-rotor Darrieus’ maximum value was 0.42 at a TSR of 2.62 and the existing hybrid VAWT’s value was 0.41 at a TSR of 2.5. Positive [Formula: see text] values at all azimuths demonstrate that the proposed hybrid wind turbine can start entirely on its own. In comparison to the existing H-rotor and hybrid VAWT, this novel hybrid system has shown enhanced performance parameters ([Formula: see text], [Formula: see text], [Formula: see text], output power) by around 11%–13% over a wide range of wind speeds.

Physical intelligence-based working mode adaptable triboelectric nanogenerator for effective wind energy harvesting in broad range

Triboelectric nanogenerators (TENGs) offer a promising solution for harvesting wind energy, which is a renewable source of natural energy that can be dissipated. However, designing a wind energy harvester presents a significant challenge due to the dynamic characteristics of ambient wind, including irregularity and broad wind speed ranges. In this work, we suggested a spontaneous working mode changeable TENG (SM-TENG) designed for effectively harvesting wind energy within a broad range of wind speeds ranging from a breeze of 2 m/s to a gale of 25 m/s. The SM-TENG consists of a physical intelligence-based rotator that can switch contact and separation mode depending on the input wind speed. Under a breeze, the SM-TENG can generate triboelectricity by fluttering a dielectric film based on vertical contact separation (F-TENG) due to intentional pressure imbalance. Meanwhile, when wind speed exceeds a certain wind speed of 5 m/s, the SM-TENG begins to harvest more wind by rotating the rotator based on the sliding contact separation (R-TENG), indicating that the SM-TENG can harvest wind by selecting the appropriate working mode. We adopted the Taguchi method to enhance performance by identifying the optimal parameters, affecting the desired output. In addition, the SM-TENG can successfully power a light-emitting diode display and a Bluetooth thermometer within a wide range of wind speeds. Therefore, this work may provide a strategy for designing a wind energy harvester capable of harvesting in a wide range of wind as well as 0could contribute to the feasibility of Internet of Things through distributed energy.

Analytical models for characterizing coupling effects of loading state and loading rate on ultimate strength and yield strength of riveted joints

An electromagnetic split Hopkinson tensile bar system was employed to determine the dynamic mechanical behaviors of riveted joints under different shear/tension combinations. Combining with results obtained from quasi-static tests, the effects of loading state and loading rate on both ultimate strength and yield strength of riveted joints are analyzed. An obvious elevation for the levels of yield force and ultimate force when increasing the loading speed is observed, meanwhile, such strengthening effects are sensitive to the loading state. On the basis of detailed load analysis, two analytical models considering both the loading rate effect and loading state effect were proposed to predict the ultimate strength and yield strength under different loading conditions. The theoretical calculations by applying such two analytical models agree well with the experimental results under five different loading states over a wide range of loading speeds (5 × 10-6 m/s ∼ 17 m/s), indicating the coupling effect of loading angle and loading speed on both ultimate strength and yield strength of riveted joint is reasonable defined.

Speed-Adaptive Model-Free Path-Tracking Control for Autonomous Vehicles: Analysis and Design

One of the challenges of autonomous driving is to increase the number of situations in which an intelligent vehicle can continue to operate without human intervention. This requires path-tracking control to keep the vehicle stable while following the road, regardless of the shape of the road or the longitudinal speed at which it is moving. In this work, a control strategy framed in the Model-Free Control paradigm is presented to control the lateral vehicle dynamics in a decoupled control architecture. This strategy is designed to guide the vehicle through trajectories with diverse dynamic constraints and over a wide speed range. A design method for this control strategy is proposed, and metrics for trajectory tracking quality, system stability, and passenger comfort are applied to evaluate the controller’s performance. Finally, simulation and real-world tests show that the developed strategy is able to track realistic trajectories with a high degree of accuracy, safety, and comfort.

Upgraded design methodology for airframe/engine integrated full-waverider vehicle considering thrust chamber design

An upgraded airframe/engine integrated design approach for a full-waverider vehicle considering thrust chamber design is proposed. Compared with the existing design approach of the full-waverider vehicle, the isolator, the combustor, and the nozzle are designed complementally. First, the airframe and inlet are generated using the full-waverider theory, the isolator with the centroid offset variable cross-section is designed using the geometric morphing method, and the maximum thrust nozzle is obtained by the method of characteristics. Coupled with a circular cross-section combustor and air rudders, a complete full-waverider vehicle including the thrust chamber is generated. Second, the correctness and the availability of the design method is verified through numerical simulations under the design condition. Finally, the aerodynamic performance of the full-waverider vehicle is analyzed under a wide-speed range in the moment equilibrium state. The optimal lift-to-drag ratio of the entire vehicle is 4.03 appearing at 4° angle of attack. Owing to the rudder deflection, the optimal lift to drag ratio reduces from 4.03 to 2.44, and the corresponding angle of attack changes as well. Moreover, the inlet unstart phenomenon occurs with the decrease of the Mach number and with the increase of the angle of attack.

Instantaneous torque error compensation based online torque sharing function for Switched reluctance Machines

An online torque sharing function (TSF) with instantaneous torque error compensation method for switched reluctance machines is proposed to maintain a minimized ripple operation. The proposed method adjusts the shared torque between the phases based on instantaneous torque error different than the existing TSF methods formulated with a mathematical expression. The objective of this approach is to benefit from the outgoing phase torque as it has slow current dynamics due to the high inductance. Also, the incoming phase is turned on as soon as it can generate positive torque. During this process, the total torque is estimated instantaneously using lookup tables, and a correction current is calculated and injected into the incoming phase reference current as the inductance is low and current dynamics are fast. This way, the torque ripple is reduced for a wide speed range. Compared to the conventional linear, sinusoidal, exponential, and cubic TSFs, better torque ripple performance is obtained.

Parameter Identification of Switched Reluctance Motor SRM Using Exponential Swept-Sine Signal

Switched reluctance motors (SRMs) received major interest in several domains, e.g., in electric vehicles. This interest is due to the many advantages of SRMs, including operation at a wide range of speeds, high performances, low cost, robustness to run under degraded conditions, and controllability. One of the major aspects in the design and implementation of controllers for SRMs is the estimation of the motor parameters. An accurate estimate of these parameters is a challenge due to the highly nonlinear behavior of SRMs in addition to their magnetic saturated operating mode to maximize the energy transfer. This paper aims at estimating the parameters of SRM by developing a new SRM model using an analytical technique. The proposed technique is based on a parallel connection of several Hammerstein models that have polynomial nonlinearity. The model is driven by a swept-sine signal, and then finite element method analysis is performed to estimate the SRM parameters. The effectiveness of the proposed method is highlighted by numerical simulation. All these simulations were performed using MATLAB/SIMULINK.

Modeling and analysis of oil frictional loss in wet-type permanent magnet synchronous motor for aerospace electro-hydrostatic actuator

To improve the power density and simplify the seal structure, the Wet-Type Permanent Magnet Synchronous Motor (WTPMSM) technique has been applied to aerospace Electro-Hydrostatic Actuators (EHA). In a WTPMSM, the stator and the rotor are both immersed in the aviation hydraulic oil. Although the heat dissipation performance of the WTPMSM can be enhanced, the aviation hydraulic oil will cost an extra oil frictional loss in the narrow airgap of the WTPMSM. This paper proposes an accurate oil frictional loss model for the WTPMSM, in which the wide speed range (0–20 kr/min) and the narrowness of the airgap (0.5–1.5 mm) are its features. Firstly, the mechanism of the oil frictional loss in the airgap of the WTPMSM is revealed. Then an accurate oil frictional loss model is proposed considering the nonlinear influence caused by the Taylor vortex. Furthermore, the influence of motor dimensions on oil frictional loss is analyzed. Finally, the proposed oil frictional loss model is verified by experiments, which provides a guideline for engineers to follow in the WTPMSM design.

Vector-controlled Y-connected three-phase induction motor drives: small-signal stability study during IGBT short-circuit fault

<p>The stability analysis is one of the most important elements to describe the performance of AC drive systems under both dynamic and steady-state operating circumstances. This is particularly essential because electric motors operate over a wide range of speeds and utilize complex control systems such as field-oriented control (FOC). This study establishes a small-signal stability analysis (SSSA) in a 1-horsepower vector-controlled Y-connected three-phase induction motor (YCTPIM) drive during an insulated gate bipolar transistor short-circuits failure (IGBT-SCF). In the beginning, a vector control system that is based on the indirect rotor FOC (IRFOC) method is described for post-fault functioning of the YCTPIM while the IGBT-SCF is taking place. After that, a small-signal model of the system that has been provided is explored. This model is based on a voltage-current model, and it is constructed by linearizing the non-linear dynamic equations of the system. During IGBT-SCF, an IRFOC strategy as well as SSSA operations are carried out on the 1-HP, 380 V, and YCTPIM. In this research, both analytical and simulation-based methodologies are applied.</p>

Design and Multiobjective Optimization of Dual-Circulation Cooling System Considering Electro-Thermal Coupling for IPMSM

Benefiting from high power density, high reliability, and wide speed range, interior permanent magnet synchronous motors (IPMSM) have received unprecedented attention. However, due to torque ripple and heat dissipation difficulties caused by the compact structure, the development of IPMSM is not smooth in high-end applications such as electric vehicles. In this article, a dual-circulation cooling system consisting of an external housing water-cooling cycle and an internal rotor-stator air-cooling cycle based on improved magnetic circuit design is innovatively proposed. While the electromagnetic characteristics are substantially improved, the temperature rise problem is also significantly suppressed and weakened. Furthermore, to further optimize multiphysics performance for the IPMSM equipped with this system, an improved multiobjective optimization model considering electro-thermal coupling is studied. Optimization effect is greatly improved by the flexible application of segmented orthogonal experiments, correlation/interaction analysis, and intelligent surrogate model/advanced algorithm. Computational fluid dynamics (CFD) and finite element analysis (FEA) highlight the advantages of proposed dual-circulation cooling system and improved optimization model. Their design rationality, effectiveness, and engineering practicability have been well verified through a series of comparative analyses.

Performance Improvement for Double-Stator Axial Flux SRM Using a New Winding Reconfigurable Power Converter

This paper presents a new power converter topology that enables reconfigurable winding operation in a double stator axial flux switched reluctance motor (DSAFSRM). The proposed power converter allows the winding working in series and parallel connection methods and requires fewer components. By applying the reconfigurable winding converter and implementing the mode selection scheme, both the wide speed range of the parallel mode and the high efficiency of the series mode are obtained, thus achieving high-efficiency operation over a wide speed range. At first, the topology and operating modes are introduced. The six available working states are also detailed. Then the drive system simulation model with the reconfigurable winding power converter is established in the MATLAB/Simulink environment. The steady-state performance of the two modes and the dynamic switching performance are simulated and analyzed. Finally, the DSAFSRM drive based on the reconfigurable winding converter is built and experimentally tested. The performance results verify the validity and correctness of the presented power converter.

Study on the flow field of a kerosene-fueled integrated inlet-combustor-nozzle oblique detonation engine

In this study, a large-scale kerosene-fueled oblique detonation engine with a design point of Mach 10 is proposed. The flow combustion characteristics and the propulsive performance considering the wall viscous drag of the detonation engine are investigated using numerical simulation methods with a detailed combustion mechanism. The accuracy of the numerical results is verified by comparing it with the detonation wave pole curve of kerosene fuel. The result demonstrates that the combined injection method consisting of wall and center-strut injectors can meet the requirements of fuel mixing in the oblique detonation engine and a stabilized oblique detonation wave is successfully formed in the combustor. The decrease in the fuel equivalent ratio leads to an increase in the non-uniformity of the temperature distribution behind the detonation wave and the decrease in the wave angle. The advantage of the oblique detonation wave in hypersonic propulsion is its easy adjustment and can achieve flight over a wide-speed range. The combustion heat release behind the wave is closer to the upper part of the wave surface as the incoming Mach number decreases. The oblique detonation engine proposed in this study can still generate stable net specific impulse at non-design point flow Mach numbers. The net specific impulse can reach 715 s at a non-design point speed of Mach 8. It proves the feasibility of wide-speed range flight applications of oblique detonation engines.

Predictive understanding of the surface tension and velocity of sound in ionic liquids using machine learning.

Knowledge of the physical properties of ionic liquids (ILs), such as the surface tension and speed of sound, is important for both industrial and research applications. Unfortunately, technical challenges and costs limit exhaustive experimental screening efforts of ILs for these critical properties. Previous work has demonstrated that the use of quantum-mechanics-based thermochemical property prediction tools, such as the conductor-like screening model for real solvents, when combined with machine learning (ML) approaches, may provide an alternative pathway to guide the rapid screening and design of ILs for desired physiochemical properties. However, the question of which machine-learning approaches are most appropriate remains. In the present study, we examine how different ML architectures, ranging from tree-based approaches to feed-forward artificial neural networks, perform in generating nonlinear multivariate quantitative structure-property relationship models for the prediction of the temperature- and pressure-dependent surface tension of and speed of sound in ILs over a wide range of surface tensions (16.9-76.2 mN/m) and speeds of sound (1009.7-1992m/s). The ML models are further interrogated using the powerful interpretation method, shapley additive explanations. We find that several different ML models provide high accuracy, according to traditional statistical metrics. The decision tree-based approaches appear to be the most accurate and precise, with extreme gradient-boosting trees and gradient-boosting trees being the best performers. However, our results also indicate that the promise of using machine-learning to gain deep insights into the underlying physics driving structure-property relationships in ILs may still be somewhat premature.