Engine Start-up Research Articles

Analysis of atmospheric emissions associated with on-road and inland waterway transport in Vietnam: Past, current and future control scenarios

On-road traffic usually receives higher priority for emissions control than other transport modes. To justify the emission control priority, our study provides comprehensive analysis of annual emissions from on-road traffic and inland waterway transport in Vietnam during 2010–2019. On-road transport emissions, both running and start-up, were quantified with bottom-up approach using provincial activity data and relevant emission factors which were scrutinized to reflect actual fleet technologies in each province. Inland waterway transport emissions, estimated for the first time for the country, were calculated using fuel consumption and registered vessel data. Total emissions progressively increased during the decade. On-road transport contributed predominantly, sharing from 85% for SO2 to 99.9% for CH4 in 2019. Before enforcement of lower fuel S content being effective in 2016, inland waterway contributed more to SO2 emissions (>59%). Engine start-up emissions of the on-road traffic, which have not been previously quantified, contributed significantly, e.g., up to 53% of the total evaporative VOC of the total on-road emissions in 2019. The large motorcycle (MC) fleet shared most of gaseous emissions, while diesel fleet contributed significantly to emissions of PM, carbonaceous aerosol, NOx, and SO2. Nearly half of total 20-yr GWP from the two transport modes in 2019 was from black carbon. EuroIV scenario reduces emissions by 2–72% while that of MC-50 (cut-down 50% of MC activities) reduces by 0.2–7%. The emission inventory results provide science-based information to prioritize control efforts and are useful for air quality modeling to quantify impacts of different interventions on ambient air quality.

Numerical and experimental investigation of a Mg/N2O powdered fuel rocket engine

Powdered metal fuel rocket engines, utilizing high energy density metal powder as fuel, have great potential in the development of propulsion systems for upper-stage rockets, and thrusters for attitude or trajectory control. The main challenges of this rocket engine technology currently lie in the realization of stable powder fuel supply, quick engine start-up, and high combustion efficiency. In this paper, we present a computational analysis of the reactive flow in a Mg/N2O powdered metal fuel rocket engine. Consideration in this work includes effects of a flame holder, mass flow rate ratio and entry angle of N2O on combustion efficiency. Based on the numerical simulation results, an experimental Mg/N2O powdered metal fuel rocket engine was designed, and working processes of the engine were investigated through hot fire tests with Mg powder as fuel and N2O as oxidant. A ground test system, consisting of a high-precision test bench, a fuel feed unit, an oxidant feed unit, and a measurement and control unit, was established. The test results show that the combustion of Mg powder and N2O can be sustained.

Voltage Signals Measured Directly at the Battery and via On-Board Diagnostics: A Comparison

Nowadays, cars are an essential part of daily life, and failures, especially of the engine, need to be avoided. Here, we used the determination of the battery voltage as a reference measurement to determine possible malfunctions. Thereby, we compared the use of a digital oscilloscope with the direct measurement of the battery voltage via the electronic control unit. The two devices were evaluated based on criteria such as price, sampling rate, parallel measurements, simplicity, and technical understanding required. Results showed that the oscilloscope (Picoscope 3204D MSO) is more suitable for complex measurements due to its higher sampling rate, accuracy, and versatility. The on-board diagnostics (VCDS HEX-V2) is more accessible to non-professionals, but it is limited in its capabilities. We found that the use of an oscilloscope, specifically the Picoscope, is preferable to measure battery voltage during the engine start-up process, as it provides more accurate and reliable results. However, further investigation is required to analyse numerous influences on the cranking process and the final decision for the appropriate measurement device is case specific.

Estimation of a Craig–Bampton equivalent model using a hybrid particle swarm optimization for DCLA purposes

It is common practice in industry to deliver a Craig–Bampton reduced version of the spacecraft’s finite element model to the launch authorities to perform the dynamic coupled load analyses. During the dynamic coupled load analyses, the finite element model of the spacecraft is coupled with the finite element model of the launcher to predict the responses caused by the vibration environment produced during the launch phases (e.g., lift-off, engine start-up, etc.). Before being Craig–Bampton-reduced, the finite element model needs to be correlated and validated against physical test results to guarantee its capability to reproduce the actual behaviour of the physical hardware, which is essential to perform a meaningful dynamic coupled load analyses. Given the complexity and size of the finite element model, the entire process can be very demanding. In this paper, an alternative to the mathematical models usually used in the dynamic coupled load analyses is investigated. The main idea is to synthesize a Craig–Bampton equivalent model directly from the response data of a vibration test experiment. The system identification problem is solved using a particle swarm optimization algorithm, tailored specifically for this type of application, the hybrid PSO and Local Search (hPSO-LS). A mutation operator from genetic algorithm is used to improve the solution and the local search method to refine the final result. The proposed method is numerically tested on a 5-degrees of freedom lumped mass system, with full stiffness and damping matrices. A sensitivity analysis of the search space size is also carried out to investigate its influence on the final results. The hPSO-LS is tested in both noise-free and noisy scenarios.

Kyoto Fusioneering’s Mission to Accelerate Fusion Energy: Technologies, Challenges and Role in Industrialisation

Making fusion power viable both technologically and commercially has been a challenge for decades due to the great complexity of the science and engineering challenges. In recent years, changes in both government policies and the emergence of private fusion companies have ushered a newfound push to accelerate fusion energy development. Kyoto Fusioneering (KF) is a privately funded fusion engineering start-up, founded to accelerate the development of high performance, commercially viable technologies that will be required for a fusion power plant, specifically those associated with heating and current drive systems, power generation, and the tritium fuel cycle. The company is focused on supporting the rapid expansion of the budding fusion industry. This paper provides a high-level description of some of the technical and industrial challenges it is tackling in developing a commercial fusion reactor, in particular in relation to: plasma heating with gyrotrons, tritium handling and breeding, energy conversion, and fusion materials. It provides an overview of KF's activities in finding solutions to challenges in each of these areas, including via its new testing facility now under construction, UNITY (Unique Integrated Testing Facility). KF’s core capabilities and areas of R&D focus are discussed, with reference to how they benefit the development of a new fusion industry as a whole and bring the technology closer to industrialisation, including via UNITY and through collaboration with external partners. The importance of industrialisation and subsequently commercialisation is also discussed, through KF’s assessment of the newly emerging fusion ecosystem, and where KF as a company sits within it.

Delamination analysis of a ductile phase-toughened environmental barrier coating for oxygen-rich turbopumps

The turbine in an oxygen-rich turbopump subjects materials to high-pressure gaseous oxygen environments, where the risk of metal fires presents a potentially catastrophic failure mode. A candidate approach for mitigating particle impact ignition, one key metal ignition mechanism, is to coat metallic components with an inert ceramic environmental barrier coating; however, such coatings are susceptible to delamination during the rapid thermal transients upon engine startup and shutdown. Here, we investigate the delamination risk of a ductile phase-toughened composite environmental barrier coating under a nominal flight cycle of a reusable boost-stage rocket engine. The coating of present interest comprises a borate-based glass-ceramic matrix reinforced with Ni and is applied as an aqueous slurry that bonds to the substrate upon firing. We first varied the Ni content in the coating and characterized its structure, finding that the Ni reinforcement sinters to the substrate and percolates through the brittle glass-ceramic when the Ni volume fraction exceeds 0.3, in excellent agreement with percolation theory. We also experimentally assessed the thermomechanical properties of the coating and used these measurements to compute its energy release rate under the thermal transients expected in service. Our analysis shows that thermal stresses and energy release rates are greatest during engine startup and shutdown, with energy release rates on the order of 100 J/m2 for a 100-μm thick coating on an IN718 substrate. Our analysis then highlights strategies for reducing the energy release rate, which include tailoring the thermal expansion coefficient to balance transient vs. steady-state thermal stresses and using active heating to promote film boiling upon exposure to cryogenic liquid oxygen, thus mitigating the severity of cold shocks. Most importantly with respect to materials design, we predict that interpenetrating composite coatings with Ni concentrations greater than 0.3 exhibit enhanced toughness via crack bridging, allowing them to resist delamination under even the most aggressive operating conditions. These results highlight the potential of high-toughness metal/ceramic interpenetrating composite coatings in thermal and environmental protection applications where extreme thermal transients delaminate conventional monolithic ceramic coatings.

Influence of the In-Cylinder Catalyst on the Aftertreatment Efficiency of a Diesel Engine

The article discusses the use of a catalyst inside the cylinder, the task of which is to reduce exhaust emissions from a diesel engine. The catalyst (platinum) applied to the glow plugs provided an additional method of exhaust aftertreatment. Due to their usage, especially in urban driving, passenger cars are characterized by small mileage between individual trips, so they often operate from a cold engine start and work at a low engine temperature, which leads to reduced catalytic reactor efficiency. For this reason, the efficiency of the internal catalyst was tested in relation to the efficiency of the external reactor. This efficiency was determined based on exhaust emission measurements (before and after the catalytic reactor) in two stages: stage 1: idling of a hot engine, and stage 2: simulation of the NEDC test (valid for the selected test object). The tests were carried out on an engine dynamometer, where the traffic conditions from the type-approval test carried out on a chassis dynamometer could be replicated. The tests were carried out on a Euro 4 1.3 JTD MultiJet diesel engine. The results (measurement of carbon monoxide, hydrocarbons, and the number of particles) related to the assessment of the effect the catalyst in the cylinder were discussed. The obtained catalytic reactor efficiency results, regardless of the type of research, indicated that it achieved the highest efficiency in reducing the concentration of hydrocarbons, and the lowest—in relation to the number of solid particles (as that is not its primary function). It is particularly significant that the in-cylinder catalytic converter was most efficient during the cold engine start, which happens frequently in urban driving. The efficiency of the diesel oxidation catalytic reactor (DOC) during the engine start-up and warm-up phases with the use of standard glow plugs reached values of 31.3%, 34.1% and 14.3%, respectively, for carbon monoxide, hydrocarbons and the particle number. On the other hand, the determined efficiency of the DOC in a setup with the modified glow plugs was 28.9%, 35.7% and 12.5%, respectively. The proposed solution can be used to improve the combustion quality in internal combustion engines used in hybrid vehicles, which are characterized by frequent engine starts and stops. In addition, it is possible to use such a solution retroactively in traditional vehicles powered by an internal combustion engine, which could result in an improvement in their emission class through what is called retrofitting.

Impact of the Internal Combustion Engine Thermal State during Start-Up on the Exhaust Emissions in the Homologation Test

Due to the increasingly restrictive exhaust emissions requirements from conventional vehicles, the internal combustion engine start-up seems to be most important part of engine operation. The period immediately after starting the engine is the time when the exhaust emissions are highest, thus, this aspect is currently subject to heavy analysis. The article evaluates the impact of the engine thermal state during its start-up for a Euro 5 emission class vehicle type approval test. The engine thermal state during start-up turned out to have a crucial influence (throughout the approval test) on the results of the hydrocarbons road emission (a difference of about 1500%) and the road emission of carbon monoxide (63%). The remaining road exhaust emission values were less sensitive to the thermal state of the engine during start-up—the nitrogen oxides emission value increased by 18% (for a cold start compared to a hot start), and the road fuel consumption (and thus the emission of carbon dioxide) increased by about 6%. In conclusion, the authors refer to technical solutions that may have a significant impact on reducing the exhaust emissions in the considered period of engine cold start.

The working process of the electric starter engine start system with a direct-on-line starter

Starting properties are the main operational ones, on which the reliability of low-temperature start-up of heat engines of automotive equipment depends. Reciprocating heat engines of internal combustion begin to work stably at a certain, relatively high frequency of crankshaft spinning by a starting device. The article discusses the working process of starting the engine with a direct-on-line electric starter, which is the theoretical basis for designing electric starter start systems for engines of new automotive and tractor equipment. Keywords: storage battery, starter circuit, starter, drive, starting properties, torque resistance, indicator torque, minimum starting frequency. 375199@mail.ru

Engine startup with a reduced level of cryogenic propellants under microgravity conditions

For missions that involve launching satellites into sun-synchronous orbits, the load-carrying capacity can be improved by regulating the time distribution of different flight phases if a transfer orbit is planned. However, this will shorten the last burn time of the engines. This paper introduces the technologies to ensure a reliable engine restart after coasting when only a reduced level of propellants is left. The influence mechanism of different flight profiles on the carrying capacity is analyzed first. Then a joint simulation method integrating the attitude control and fluid dynamics is proposed that can accurately analyze the sloshing features of the cryogenic propellants and their influences under microgravity conditions. Finally, a guidance method is studied that eliminates the attitude deviations at the shutdown time of the first burn to suppress additional propellant sloshing during the follow-up coasting phase. The high-fidelity simulation system reveals the feasibility of a low level scenario, and with the action of the updated guidance method, the pressure drop can be controlled as needed and the sloshing can be well restrained, matching the existing pressurization ability and requirements for re-ignitions of engines. These technologies are applied in the successful launch of the LM-8/Y2 mission, in which the performance improvement is verified.

Features of starting motor vehicles diesel engines with the use of molecular energy storages

Problem. With the experience of special purpose vehicles operating in the field, there is a problem of electrical start-up of diesel engines at low temperatures. It is caused by an increase in the motor oil viscosity, as well as a decrease in the starter batteries capacity. Goal. The goal of the work is to investigate the possibilities of using molecular energy storage for the reliable diesel engines start-up, including in low temperatures, aimed at improving the efficiency of the electrical start-up systems of special purpose vehicles diesel engines, which are operated in the field. Methodology. Methods of mathematical statistics were used in the study of the characteristics of molecular energy storage. When justifying the characteristics of the diesel engines electrical start-up system with molecular energy storage, mathematical methods of operations research were applied. Methods of mathematical analysis were used in the development of a diesel start-up system scheme. Results. The functional scheme of the electrical start-up system of diesel with a molecular energy storages is proposed. Originality. There are the known ways to facilitate the launch of diesel engines in low temperatures, such as the engine pre-growing or the heating of the air entering the engine combustion chambers, but they lead to a rapid discharge of starter batteries. This may make it impossible to start the diesel engine. The use of molecular energy storage will ensure a reliable start-up of a cold diesel engine. Practical meaning. The use of a combined electricity source, consisting of batteries and molecular energy storage, provides a reliable start-up of the engine in extreme temperature conditions, reducing the batteries capacity, increasing their service life, and cutting down operating costs.

Visualization of soot formation in load transients during GDI engine warm-up

Reducing the emissions of pollutants, and particularly soot particles, from internal combustion engines is one of the greatest challenges faced by car manufacturers. Although modern gasoline direct injection (GDI) engines produce relatively low particulate emissions during steady state operation under near-stoichiometric conditions, they can produce much higher particulate emissions during transients that cause abrupt changes in load, fuel consumption, and the air-to-fuel ratio. Emissions during transients are particularly high when the engine coolant temperature is low, as occurs during engine start-up. Consequently, there is a need to find ways of reducing particulate emissions during load transients. This paper therefore investigates particulate formation during load transients in a single-cylinder GDI engine equipped with an endoscope in the cylinder head. A transient sequence was designed in which the engine load was increased from 4 bar NMEP to a maximum of 12 bar NMEP in 2 s at an engine speed of 2000 rpm. During the transients, the engine’s particulate emissions were measured in terms of particulate number (PN) and images of the combustion process inside the cylinder were captured via the endoscope using a high-speed camera to identify locations where soot formation occurred. Experiments were conducted at a range of coolant temperatures and using different injection strategies to determine how these parameters affect PN emissions. The coolant temperature was found to be the dominant factor governing PN emissions during transients. Luminescence data obtained by analyzing the flame images agreed well with the measured PN emissions during transients. Under all varied parameters in the transients except delayed injection, soot was mainly formed from wall films. For transients with delayed fuel injection, much of the piston film could be avoided but soot formation instead became mixing-dominated. Variation of the air-fuel ratio had little effect on PN emissions during transients. At all coolant temperatures, PN emissions were lowest when using a split injection strategy but delaying the injection timing increased PN emissions even though the endoscope images suggested a lower frequency of diffusion flame formation. No conditions were found under which the PN emissions during transients with low coolant temperatures could be reduced to levels comparable to those seen with warm coolant.

Sintering-resistant and highly active Au/SBA-15 catalyst for carbon monoxide oxidation

The low thermal stability of gold-based catalysts is a significant obstacle to their practical application, especially under demanding conditions, such as those prevailing in automotive exhaust gas converters. In this work, we demonstrate that it is possible to strongly anchor 2–3 nm size gold nanoparticles inside the pores of SBA-15 mesoporous silica. The Au/SBA-15 catalyst showed high thermal stability, even at a temperature of 700–800 °C. The gold was evenly distributed inside the SBA-15 mesopores using the adsorption of the [Au(en)2]Cl3 complex (en = ethylenediamine) in an alkaline environment. Due to the very small size of gold nanoparticles, the obtained catalyst was highly active in low-temperature CO oxidation. The high resistance of Au particles to sintering can be explained by the confinement effect and the strong metal-support interaction, induced during the catalyst precursor decomposition under an oxygen-free atmosphere at 400 °C. The carbonaceous layer, formed from ethylenediamine ligands decomposition, plays an essential role in stabilizing gold nanoparticles inside the SBA-15 pores. We believe that our findings may contribute to solving the problem of carbon monoxide emission during engine start-up.

Atmega328p microcontroller based biometric starting system design for caterpillar D3k dozer heavy operators

Heavy equipment industry is an employment sector with potentially high rate of accidents, which might occur due to the operator's own fault, where he or she does not have competence in operating such an equipment. This operator's fault accident ranks number two after that of the mechanic's accident rate, which is the focus of this research. In line with the latest digital electronic development, companies have been able to solve problems confronted with operators, one of which is through the application of biometric authorization device, which has been expected to be able to reduce the rate in the industrial accidents in heavy equipment rental. This device works by requiring authorization of the operator without inserting the manually inserted ignition key to the machine, but the operator's fingerprint that has been authorized into the system to operate such a machine. This, in turn, Will be able to reduce risks of getting an accident among operators. Fingerprint has its function to recognize the operator's identity as well as password to the electronic Ignition key to the machine that not everybody can get access to operating the machine to start it up. Design of this electronically control device is to produce biometrically engine start-up replacing the currently recognize Ignition switch to crank and switch off the engine using microcontroller ATmega328P system. Results of the study gained from the tests based on the standard operating procedures show based on the standard Operating procedures show a 100% success without any obstacles.

Dynamic response control of centrifugal pendulum vibration absorber with motion-limiting device during startup in gravity field

The dynamic performance of a vertically rotating centrifugal pendulum vibration absorber (CPVA) during engine start-up was investigated. The equations of motion were established using a Lagrange equation of the second kind containing terms for gravity and the motion-limiting device of the absorber, respectively. The optimal positioning of the motion-limiting device was determined from the perspective of CPVA stability and damping capability, and the terminology for the CPVA damping quality factor was defined to evaluate the damping capability of the absorber. Simulink models were established to simulate the behaviour of the absorbers at different speeds during engine initiation and assess the impact between the absorber and motion-limiting device during engine start. Based on the results, the concept of knocking power was proposed, and it was shown that resonance occurring during engine start worsens the noise, vibration and harshness (NVH) performance of the system. It was further shown that the initial position of the absorber at the moment of engine start to turn affects the knocking power and, as a result, the startup noise of the CPVA. The study also finds that the transient position of the absorber at the engine ignition time affects the knocking power. The responses of CPVA under different working conditions were tested on an electric bench and compared with simulation results. Based on our results, we propose several measures to control absorber behaviour and reduce knocking power.

Electrical Disturbances in Terms of Methods to Reduce False Activation of Aerial Fire Protection Systems

The paper presents an analysis of false triggers of fire protection systems installed on aircraft. They not only cause task interruption but also have a direct impact on flight safety, forcing the crew to land in a risky area. Simulation models of electronic actuators were developed to determine the conditions under which false alarms occur. Testing of the simulation models was carried out in the computational package Matlab-Simulink and Circum-Maker for different electrical disturbance generation conditions. The simulation of overvoltage, voltage drops and voltage decays in the on-board electrical network supplying the fire protection system, occurring during the start-up of aircraft engines and during the switching on and off of on-board high-power devices, was studied. The conducted studies have practical applications since the simulation results are an important element for planning experimental tests of the SSP-FK-BI executive blocks under electrical disturbance conditions. Based on the simulation and experimental studies, the conditions causing false tripping of the fire protection system and the parameters for selected disturbance factors have been determined.

Experimental Investigation on Combustion and Performance of Diesel Engine under High Exhaust Back Pressure

The use of exhaust gas recirculation, complex after-treatment systems, advanced technology of high-strength engines, and underwater exhaust will lead to increased diesel exhaust back pressure (EBP). This will increase the residual exhaust gas and the exchange temperature in the cylinder and reduce the fresh air charged in the next cycle. In this work, the effects of two high EBP conditions (10 kPa and 25 kPa) on the performance of medium-speed ship engines under different loads are explored through experiments. The results show that the increase in EBP from 10 kPa to 25 kPa has little effect on the heat release rate, engine power, and engine start-up time. However, it will lead to ignition advance and the maximum pressure rise rate, peak pressure, and exhaust temperature increase. The increase in EBP has a more significant impact on the small valve overlap angle. Because the reduction in the valve overlap angle has led to an increase in the residual exhaust gas, further increases in EBP causes residual exhaust gas effects to be more pronounced. The effect of increasing EBP on fuel consumption depends primarily on which effect of exhaust back pressure on temperature and fresh air intake dominates.

Delayed Supply of Lubricant to Frictional Pairs in Engine Startup

Delayed Supply of Lubricant to Frictional Pairs in Engine Startup

A Moment-of-Inertia-Driven Engine Start-Up Strategy for Four-Wheel-Drive Hybrid Electric Vehicles

During the moment-of-inertia (MoI) start-up process, an engine is cranked to ignite at 800 rpm with better fuel efficiency than at 250 rpm in the belt-driven start. As kinetic energy is employed, the work needed to crank the engine is also reduced. This article aims to develop an MoI-driven engine start-up method for a four-wheel-drive (4WD) vehicle. By modeling a 4WD hybrid electric vehicle (HEV) powertrain, a system dynamics model is developed into a state-space equation. The variable operating conditions of the engine and clutch are identified, and an adaptive model predictive controller (MPC) is designed. The goal of multioptimization is to control the engine speed trace, minimize the front and total axle torsion speed, and execute the torque demand. The optimization outputs are the engine torque set points, front electric motor (EM) torque set points, clutch nominal force set points, and rear EM set points. By predicting the engine fluctuation torque and considering the power source component constraints, an optimization algorithm is developed. This strategy is simulated and verified on the vehicle and powertrain models. The results indicate that the proposal achieves distinct fuel consumption improvement with an optimized drivability performance.

Studies on the Effects of Cold Starts of the Ship Main Engine

Abstract This article presents the influence of various ship’s operational conditions occurring during manoeuvres related to entering and leaving the ports and mooring operations. Frequent starts and stops of the ship’s propulsion unit are then required, which affect the variability of the energetic loads of the ship’s power plant, causing accelerated, non-design wear of the ship’s main propulsion engine. The effects of cold start-ups of the main ship engine are the subject of this study. Conditions of the engine inlet valve damage process are discussed. The physics of the degradation process leading to air inlet valve damage was considered. Laboratory tests of structure continuity and their results are discussed, and the valve material defects were excluded as the cause of the damage. The causes of repeated damage to the inlet air valves were identified. The effectiveness of the performed corrective measures was confirmed by a documented control test of the engine start-up. The article is a utilitarian premise for the requirements of the Classification Society.