Simulation Of Engineering Systems Research Articles

Li-Ion Battery Immersed Heat Pipe Cooling Technology for Electric Vehicles

Lithium-ion batteries, crucial in powering Battery Electric Vehicles (BEVs), face critical challenges in maintaining safety and efficiency. The quest for an effective Battery Thermal Management System (BTMS) arises from critical concerns over the safety and efficiency of lithium-ion batteries, particularly in Battery Electric Vehicles (BEVs). This study introduces a pioneering BTMS solution merging a two-phase immersion cooling system with heat pipes. Notably, the integration of NovecTM 649 as the dielectric fluid substantially mitigates thermal runaway-induced fire risks without requiring an additional power source. Comprehensive 1-D modeling, validated against AMESim (Advanced Modeling Environment for Simulation of Engineering Systems) simulations and experiments, investigates diverse design variable impacts on thermal resistance and evaporator temperature. At 10 W, 15 W, and 20 W heat inputs, the BTMS consistently maintained lithium-ion battery temperatures within the optimal range (approximately 27–34 °C). Optimized porosity (60%) and filling ratios (30–40%) minimized thermal resistance to 0.3848–0.4549 °C/W. This innovative system not only enhances safety but also improves energy efficiency by reducing weight, affirming its potential to revolutionize lithium-ion battery performance and address critical challenges in the field.

GPIO-based nonsingular terminal sliding mode control for high-pressure common rail systems

The ideal fuel rail pressure is a significant component to keep the high-pressure common rail (HPCR) system work stably. The influence of time-varying fuel injection disturbance of the HPCR system is neither fully considered nor well dealt with in traditional rail pressure control approaches. To this end, the rail pressure tracking problem of an HPCR system is investigated in this paper using a generalized proportional integral observer (GPIO)-based composite control algorithm. A nonlinear model of the HPCR system is first established based on fluid dynamics and mechanics laws. Then, a GPIO is utilized to observe the time-varying fuel injection disturbance. Based on the design of a nonlinear sliding surface using the disturbance estimation, a GPIO-based nonsingular terminal sliding mode control (NTSMC) method is proposed to achieve a better rail pressure tracking control performance and a stronger robustness. Finally, a group of simulations in the MATLAB/Simulink environment and experiments in a more realistic Advanced Modeling Environment for performing Simulation of engineering systems (AMESim) environment are conducted, the results of which demonstrate the advantage and effectiveness of the proposed method.

A refrigerant-injection heat pump-based efficient integrated thermal management system for electric vehicles approaching the wide temperature range in China

The integrated thermal management system of electric vehicles is responsible for the temperature regulation of the cabin and electrical system. The wide temperature range of vehicles specifies the operating conditions required for different regions, which is −33 – 39 °C in China. Through experimental studies conducted on heat pump systems and thermal analyses of electrical systems, this study innovatively developed an efficient integrated thermal management system based on a refrigerant-injection heat pump. In addition, a simulation platform for the system was established using the advanced modeling environment for performing simulation of engineering systems (AMESim) software to evaluate the system performance. The results showed that the stability and efficiency of battery cooling based on the intermediate heat exchanger were better than those obtained with a dual evaporator setup. The proposed solution could reduce energy consumption by 30% at an ambient temperature of 35 ℃. The thermal management system with the heat recovery for the motor and electric control at high temperatures could reduce the energy consumption by 11.98% – 56.69% and meet the heating condition of −22.04 ℃. The integrated thermal management system based on a refrigerant injection heat pump widened the operating range during the highway fuel economy test (EPA-420-B-12-001). Aided by electric heating, the simulation system developed in this study could satisfy the load requirements for the wide temperature range in China.

Numerical and boundary condition effects on the prediction of detonation engine behavior using detailed numerical simulations

High-fidelity numerical simulations of an experimental rotating detonation engine with discrete fuel/air injection were conducted. A series of configurations with different feed-plenum pressures but with constant equivalence ratio were studied. Detailed chemical kinetics for the hydrogen/air system is used. A resolution study for the full rotating detonation engine (RDE) system simulation is also conducted. Two kinds of boundary conditions, a total pressure boundary and a constant mass flow rate boundary, are used to assess the effects of the inlet boundary. As mass flow rate is increased, the total pressure boundary causes more error in the axial pressure distribution while the constant mass flow rate gives a better solution for all cases ran. The simulations confirm experimental findings, and reproduce qualitative as well as some of the quantitative trends. These results demonstrate that a) fuel-air mixing is highly non-uniform within the detonation chamber, leading to variations in local equivalence ratio, b) the fuel and oxidizer injectors experience significant backflow as the detonation wave passes over, but recover at different rates which further augments the inefficiencies in mixing, and c) parasitic combustion in the mixing region makes the detonation wave weak by extending the reaction zone across the wave.

AMESIM을 이용한 연료전지 냉각 시스템 성능 분석

Recently, a lot of environmental problems have emerged. One of the ways to solve the problem is the PEMFC (Proton-Exchange Membrane Fuel Cell). A PEMFC is an energy conversion device that generates electricity using hydrogen and oxygen. It is very eco-friendly because it produces water, heat, and electricity as a resulting products. However, the performance of the cooling system is very important because the performance of the PEMFC depends heavily on temperature. Therefore, in this simulation, the cooling system of the PEMFC was designed and its performance by simulation study using AMESIM (Advanced Modeling Environment for Simulation of Engineering Systems) S/W was evaluated. The design goal for thermal performance of the present cooling system is to keep the fuel cell at 80℃. Simulated results show that at higher power, PEMFC generates more heat. Therefore, greater heat exchange is required.

BUILDING DIGITAL TWINS FOR SMART CITIES: A CASE STUDY IN GREECE

Abstract. The recent emergence of the Internet of Things (IoT), the latest technological innovations and the widespread use and embrace of Building Information Models (BIMs) offer several new ideas and decision-making capabilities throughout the life cycle of the built environment. The ability to connect and monitor data from sensor networks remotely in real time as well as the simulation and optimization of engineering systems, have led to the emergence of the Digital Twin (DT) concept of the structured environment. Although BIM lacks semantic completeness in areas beyond the scope of building modelling such as control systems, cadastral systems, networking of sensors, meteorological networks, etc., the DTs aim to achieve the synchronization of big data from various sources and simulate the real world into a virtual platform for the seamless management and control of the construction process, facility management, environmental monitoring, disaster management and disaster prevention, and other life cycle processes within the built environment. DTs in the built environment are still in nascent stages and thus a more in-depth investigation is required to explore and establish the best practices and technologies to serve this evolution. In this paper, we propose a methodology for providing the DT of a building; by crossing from the BIM static world to the dynamic cyber-world of DTs. A practical application is implemented for a two-storey ‘smart’ building with sensor systems installed in its assets and in the surrounding landscape area. As the practical experiment is successfully completed, we conclude that such an endeavour can actually be achieved at building level offering several economic, environmental and social benefits.

Analysis of working characteristics of giant magnetostrictive actuator for direct-drive fuel injector

Based on the structure of direct-drive injectors, the giant magnetostrictive actuator (GMA) for direct-drive injectors designed with giant magnetostrictive materials (GMMs) shows great application prospects in the field of fuel injection. This paper establishes the mathematical model of GMA for direct-drive fuel injector. The numerical model of the GMA is built by means of the Advanced Modeling Environment for performing Simulation of engineering systems (AMEsim) simulation platform combined with the working process of the actuator. A prototype was fabricated, and the correctness of the numerical model was verified by experiments. Through AMEsim, the magnetic potential distribution law, unit step response, and frequency characteristics were analyzed, it is found that the relationship between the magnetic potential and the current on the GMM is approximately linear, and the ratio of the magnetic potential to the total magnetic potential of the magnetic circuit is about 0.9; the unit step response shows that the actuator has a fast response speed, the rise time is about 240 µs, and when the output displacement enters the 5% and 2% error bands, the adjustment time is 540 and 810 µs, respectively; by inputting the sweep signal, it is obtained that the natural frequency of the actuator is about 700 Hz, and the output amplitude is relatively “smooth” with a bandwidth of 0–250 Hz. This research enriches the research methods of GMAs and provides a novel idea for the development of high-performance fuel injectors.

Design, simulation, and experiment research on fast control system of steam turbine inlet valve

In this paper, a new fast control system of steam turbine inlet valve is designed, which is composed of the fast closing system and the fast opening system. For the first time, this paper proposes that the fast closing system is designed by means of the special structure of the slide valve in an oil servo motor on the basis of the transformation of the hydraulic control system of steam turbine inlet valve. For the first time, a differential oil discharge fast opening system is designed by use of two cartridge valves. The mathematical model of electro-hydraulic fast control system is presented. With the use of simulation software Advanced Modeling Environment for Simulation of engineering systems , the curves of parameters such as piston displacement, piston velocity, oil pressure of upper and nether cavities of oil servo motor, and flow flux of upper and nether cavities of oil servo motor are obtained. The fast closing time of the piston for whole journey from the simulation results is 0.36 s. The fast opening time of the piston for whole journey from the simulation results is 1.55 s. According to the designed structure of the fast control system, the fast control experiment system is built. The fast closing time of the piston for whole journey from the experiment results is 0.22 s. The fast opening time of the piston for the whole journey from the experiment results is 1.97 s. The simulation and experimental results show that the designed fast control system can realize the fast closing and fast opening of the inlet valve. The fast closing time of the fast control system is <0.5 s, and the fast opening time of the fast control system is <3 s, which meets the fast control time requirement of the steam turbine inlet valve. Compared with the existing fast control system products, the fast control system and the inlet valve servo regulation system share a set of oil sources. And the fast control system has the advantages of low cost, simple structure, easy implementation, etc.

Simulated research on large-excavator boom based on hydraulic energy recovery

According to the working condition characteristics of a company's existing XE series 70-ton-large-scale crawler hydraulic excavator, a new hydraulic type is designed for the purpose of energy saving, which contains an accumulator as a reversible energy storage component and a variable pump/motor as an energy conversion element. This scheme belongs to the excavator boom potential energy regeneration method. When the boom is lowered, the accumulator and the pump/motor function, part of the hydraulic cylinder rodless cavity fluid entering the rod cavity and the other part filling the accumulator with fluid and driving the pump/motor to assist the engine's work. After the boom is lowered, the accumulator continues to supply liquid to the pump/motor which carries on assisting the engine to do work. Then the main hydraulic components of the system are modeled, together with building the simulated system model in LMS Imagine.Lab AMESim(Advanced Modeling Environment for performing Simulation of engineering systems). The result of simulation manifests that this system scheme can achieve the recovery of the potential energy of the boom and realize a better energy saving effect.

Simulation of Hydraulic System Faults for Marine Machinery Based on AMESim

Zhou, W., 2019. Simulation of hydraulic system faults for marine machinery based on AMESim. In: Gong, D.; Zhu, H., and Liu, R. (eds.), Selected Topics in Coastal Research: Engineering, Industry, Economy, and Sustainable Development. Journal of Coastal Research, Special Issue No. 94, pp. 357–361. Coconut Creek (Florida), ISSN 0749-0208.With the rapid development of marine ship manufacturing, engineering machinery has become more complex, continuous and automated. It has become the focus of current research to effectively detect the hydraulic system of marine machinery using the modern scientific methods. For this, the Advanced Modelling Environment for Simulation of Engineering Systems (AMESim) was adopted in this study. By fully explaining the model of the basic hydraulic components and the parameter selection of the overall modelling for the marine machinery hydraulic system, this paper achieves the simulation design of the marine machinery hydraulic system based on the AMESim integrated platform. The comparison between the AMESim-based simulation results and the mathematical model verifies the rationality of the AMESim-based simulation for the marine machinery hydraulic system; meanwhile, compared with the simulation results based on MATLAB, the AMESim-based simulation shows good superiority, which is of great guiding significance for shipbuilding projects.

Finite Element Modelling of Thermal Behaviour of Solar Cells

Engineering Science Based on Modelling and Simulation (M & S) is defined as the discipline that provides the scientific and mathematical basis for simulation of engineering systems. These systems range from microelectronic devices to automobiles, aircraft, and even oilfield and city infrastructure. In a word, M & S combines knowledge and techniques in the fields of traditional engineering - electrical, mechanical, civil, chemical, aerospace, nuclear, biomedical and materials science - with the knowledge and techniques of fields such as computer science, mathematics and physics, and social sciences. One of the problems that arise during solar cell operation is that of heating them because of permanent solar radiation. Since the layers of which they are made are very small and thick it is almost impossible to experimentally determine the temperature in each layer. In this sense, the finite element method comes and provides a very good prediction and gives results impossible to obtain by other methods. This article models and then simulates the thermal composition of two types of solar cells, one of them having an additional layer of silicon carbide that aims to lower the temperature in the lower layer, where the electronic components stick to degradable materials under the influence of heat.

Modeling and co‐simulation based on Adams and AMESim of pivot steering system

The pivotal steering ability of vehicles is important in the case of narrow steering space. In this study, a pivot steering system for the rescue vehicle is designed, and the 1D + 3D co-simulation model is established based on automatic dynamic analysis of mechanical systems (Adams) and advanced modelling environment for performing simulation of engineering systems (AMESim). The dynamic analysis of the pivot steering system has been compared with the theoretical calculations, which proved the correction of the model. In addition, through the simulation, the authors can hold the conclusion that the tyre cornering stiffness has a great influence on the pivot steering system.

Mechanical simulation and installation position optimisation of a lifting cylinder of a scissors aerial work platform

The force of a lifting cylinder is the main factor of the alternating stress of scissors arms in a scissors aerial work platform, which seriously affects the fatigue life of structures. Aiming at this problem, the installation position parameters that affect the force of the lifting cylinder was simulated and optimised. First, the mechanical model of the lifting system was established based on the principle of virtual work, and the position parameters that affect the force of lifting cylinder were determined. Then, the advanced modeling environment for performing simulation of engineering systems (AMESim) simulation model was used to simulate the lifting process of the lifting system, and the reliability of the simulation model was verified by the pressure test of the hydraulic system. Finally, based on the simulation model, the design of experiment method was used to optimise the installation position of the lifting cylinder in the design and development environment of AMESim, and the optimisation effect was verified through the test on a real vehicle. The result shows that the peak load of the lifting cylinder is reduced by ∼12%, and the average of the steady-state value decreases by ∼20% after the installation position is optimised.

Online optimisation of fuel consumption subject to NOx constraints

Several variations of extremum seeking algorithms have been successfully used to optimise the fuel consumption in automotive engines, albeit without explicit consideration of the emissions constraints that dictate whether the engine meets legislated standards. By treating the emissions constraints as requiring satisfaction on average and assuming measurable tailpipe emissions, an augmented extremum seeking algorithm is proposed in this paper. The suggested approach utilises a constrained optimisation method developed for static plants that considers both the original cost function and a constraint function representing the satisfaction of the imposed average constraint. Existing theoretical results are modified to guarantee semi-global practical stability of the approach. The approach is then applied to a high fidelity engine and aftertreatment system simulation to find the optimal spark advance that minimises fuel consumption subject to an NOx constraint, under the assumption that appropriate sensor feedback is available. The simulation results demonstrate the potential of the proposed approach, and suggest other existing extremum seeking schemes can be readily augmented with the ability to satisfy constraints in an averaged sense.

Quasi-Dimensional Diesel Engine Combustion Modeling With Improved Diesel Spray Tip Penetration, Ignition Delay, and Heat Release Submodels

Increasingly stringent fuel economy and CO2 emission regulations provide a strong impetus for development of high-efficiency engine technologies. Diesel engines dominate the heavy duty market and significant segments of the global light duty market due to their intrinsically higher thermal efficiency compared to spark-ignited (SI) engine counterparts. Predictive simulation tools can significantly reduce the time and cost associated with optimization of engine injection strategies, and enable investigation over a broad operating space unconstrained by availability of prototype hardware. In comparison with 0D/1D and 3D simulations, Quasi-Dimensional (quasi-D) models offer a balance between predictiveness and computational effort, thus making them very suitable for enhancing the fidelity of engine system simulation tools. A most widely used approach for diesel engine applications is a multizone spray and combustion model pioneered by Hiroyasu and his group. It divides diesel spray into packets and tracks fuel evaporation, air entrainment, gas properties, and ignition delay (induction time) individually during the injection and combustion event. However, original submodels are not well suited for modern diesel engines, and the main objective of this work is to develop a multizonal simulation capable of capturing the impact of high-injection pressures and exhaust gas recirculation (EGR). In particular, a new spray tip penetration submodel is developed based on measurements obtained in a high-pressure, high-temperature constant volume combustion vessel for pressures as high as 1450 bar. Next, ignition delay correlation is modified to capture the effect of reduced oxygen concentration in engines with EGR, and an algorithm considering the chemical reaction rate of hydrocarbon–oxygen mixture improves prediction of the heat release rates. Spray and combustion predictions were validated with experiments on a single-cylinder diesel engine with common rail fuel injection, charge boosting, and EGR.

Development and Validation of a Quasi-Dimensional Dual Fuel (Diesel – Natural Gas) Combustion Model

This paper presents a newly developed quasi- dimensional multi-zone dual fuel combustion model, which has been integrated within the commercial engine system simulation framework. Model is based on the modified Multi-Zone Combustion Model and Fractal Combustion Model. Modified Multi-Zone Combustion Model handles the part of the combustion process that is governed by the mixing-controlled combustion, while the modified Fractal Combustion Model handles the part that is governed by the flame propagation through the combustion chamber. The developed quasi-dimensional dual fuel combustion model features phenomenological description of spray processes, i.e. liquid spray break-up, fresh charge entrainment, droplet heat-up and evaporation process. In order to capture the chemical effects on the ignition delay, special ignition delay table has been made. Additionally, to capture the effect of entrained methane on the chemical reaction rate, special table that features chemical reaction time scale has also been made. The start of flame propagation is calculated through the newly developed sub- model based on knock integral calculation. The existing k-e turbulence model has been extended to account for the effect of diesel pilot injection on the increase of in-cylinder turbulence level. Since in the conventional dual fuel combustion process multiple flames propagate through the combustion chamber, multiple flame propagation model has been developed. This model can describe arbitrary number of flames that propagate through the combustion chamber. The validation data for the developed quasi-dimensional dual fuel combustion model have been acquired on a 2.0 liter Diesel engine, which has been modified to operate in the conventional dual fuel combustion mode. The presented model has been validated at different loads and diesel substitution ratios, and there is a good fit between the measured and cycle-simulation data.

Pressure ripple of gear pumps affected by air content on trapped volume

A general assumption about fluid power systems is that the pressure ripple of trapped volume is a primary source for fluid-borne noise. Whereas the high frequency vibration characteristics generated by pressure fluctuations of trapped volume are different under different air content in the oil. This paper presents the non-Newtonian fluid models to describe the oil flow condition in external gear pumps. In this analysis, pressure ripple due to compressibility of fluid is considered, and the effect of pressure ripple in the trapped volume of external gear pumps has been investigated by comparing with 8 % air content and 10 % air content in the oil. It was found that the amplitude of pressure fluctuation would drop about 2.5 MPa with the increase 2 % of the air content under the same conditions of load and speed. The whole work was performed on the computational fluid dynamics (CFD) environment, an efficient tool for the simulation of dynamic engineering systems, and more particularly of fluid power.

Solar parabolic dish Stirling engine system design, simulation, and thermal analysis

Modeling and simulation for different parabolic dish Stirling engine designs have been carried out using Matlab®. The effect of solar dish design features and factors such as material of the reflector concentrators, the shape of the reflector concentrators and the receiver, solar radiation at the concentrator, diameter of the parabolic dish concentrator, sizing the aperture area of concentrator, focal Length of the parabolic dish, the focal point diameter, sizing the aperture area of receiver, geometric concentration ratio, and rim angle have been studied. The study provides a theoretical guidance for designing and operating solar parabolic dish Stirling engines system. At Zewail city of Science and Technology, Egypt, for a 10kW Stirling engine; The maximum solar dish Stirling engine output power estimation is 9707W at 12:00PM where the maximum beam solar radiation applied in solar dish concentrator is 990W/m2 at 12:00PM. The performance of engine can be improved by increasing the precision of the engine parts and the heat source efficiency. The engine performance could be further increased if a better receiver working fluid is used. We can conclude that where the best time for heating the fluid and fasting the processing, the time required to heat the receiver to reach the minimum temperature for operating the Solar-powered Stirling engine for different heat transfer fluids; this will lead to more economic solar dish systems.Power output of the solar dish system is one of the most important targets in the design that show effectiveness of the system, and this has achieved when we take into account many factors in the design of the solar dish system. One of these factors is the reflector material of the concentrator and using the results from the Matlab simulation program; where the Polymeric Film, Non Metal reflectors, with a net conversion power of more than 97.07%, still holds the conversion record than the Anod Aluminum reflectors, which has a net conversion power 85.97% with respect to the polished stainless reflectors with a net conversion power 49.52% from the 10kW Stirling engine. Where the power output differ as 9707, 4952, 8597W, respectively from the 10kW Stirling engine. It is shown that there are changes in Stirling power output for different materials, which guide us to select the optimum material, based on the targeted power output and cost. Our target to reach the optimum power that we need it in the design 10kW power output design as an example from the solar dish Stirling engine.

Architecture of model libraries for modelling turbocharged diesel engines

ABSTRACTTurbocharged diesel engines are complex engineering systems, which have a wide range of applications. Numerical simulations of the engine system for its performance, fuel economy and emissions offer affordable possibilities to improve the engine system itself and, furthermore, to optimize a larger system, such as a power plant and a marine propulsion system. As the simulation models of the diesel engines are used in a wide range of contexts, a library-based modelling approach provides benefits of making a modelling process and maintenance of the existing models easier. The model library should not be just a catalogue of the models but has to provide a solid model structure on different levels of abstraction and, therefore, guide the modeller to make appropriate decisions in a step-by-step manner at each level. Such a model structure consists of a technical component level, a physical concept level and a mathematical level. In this paper, application of the model structure to build a library for modelling turbocharged diesel engines is presented. For each level, a general framework is explained with practical examples. Finally, a procedure for building an engine system simulation model is demonstrated using a specific diesel engine model.

Charging valve of the full hydraulic braking system

It is known that the full hydraulic braking system has excellent braking performance. As the key component of the full hydraulic braking system, the parameters of the accumulator charging valve have a significant effect on the braking performance. In this article, the key parameters of the charging valve are analyzed through the static theoretical and an Advanced Modeling Environment for performing Simulation of engineering systems (AMESim) simulation model of the dual-circuit accumulator charging valve is established based on the real structure parameters first. Second, according to the results of the dynamic simulation, the dynamic characteristics of the charging pressure, the flow rate, and the frequency of the charging valve are studied. The key parameters affecting the serial production are proposed and some technical advices for improving the performance of the full hydraulic system are provided. Finally, the theoretical analysis is validated by the simulation results. The comparison between the simulation results and the experimental results indicates that the simulated AMESim model of the charging valve is accurate and credible with the error rate inside 0.5% compared with the experimental result. Hence, the performance of the charging valve meets the request of the full hydraulic braking system exactly.