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“New Space" is reshaping the economic landscape of the space industry and has far-reaching implications for technological innovation, business models, and market dynamics. This change, aligned with the digitalization in the world economy, has given rise to innovations in the downstream space segment. This “servitization” of the space industry, essentially, has led to the transition from selling products like satellites or spacecraft, to selling the services these products provide. This also connects to applications of various technologies, like cloud computing, artificial intelligence, and virtualization. Redefining Space Commerce: The Move Toward Servitization discusses the advantages of this shift (e.g., cost reduction, increased access to space for smaller organizations and countries), as well as the challenges, such as maintaining safety and security, establishing standardization and regulation, and managing risks.

With technological breakthroughs in electric land vehicles revolutionizing their respective industry, maintenance, repair, and overhaul (MRO) facilities in aviation are also adopting digital technologies in their practices. But despite this drive towards digitalization, the industry is still dominated by manual labor and subjective assessments. Today, several technologies, processes, and practices are being championed to resolve some of these outstanding challenges. Considering this, it is important to present current perspectives regarding where the technology stands today and how we can evaluate capabilities for autonomous decision support systems that prescribe maintenance activities. Overlooking some of these unsettled domain issues can potentially undermine any benefits in speed, process, and resilience promised by such systems.

The purpose of this paper is to make quantitative analysis on the effect of demand side optimization, especially on the reduction of CO2 emission realized by optimizing charging and discharging schedule of battery electric vehicles (BEVs), or by optimized Vehicle-to-Grid (V2G) operations. BEV optimization model is incorporated into the existing electricity supply-demand model to study how the introduction of BEVs make differences on a power system operation, composition of power generation and CO2 emission on the power supply side. Three cases of BEV operation are studied, 1) dumb charging without optimization, 2) optimization of charging, 3) optimization of charging and discharging with Vehicle-to-Grid operations. Analysis is also made on how de-carbonization of the supply side will make differences by studying the case of 2035 and 2040 in addition to 2030, the target year of Japan’s new national energy plan.

It is important to reduce aerodynamic drag for reducing fuel consumption. Conventionally reduction of aerodynamic drag has been carried out by shape optimization of each part of a vehicle based on the investigations of the time-averaged flows around the vehicle. However, the general tendency of drag reduction has been saturated recently and it is required to develop a new flow-control technique to achieve further reduction in aerodynamic drag. We therefore focus on the unsteadiness of the flow around a vehicle to achieve it because the aerodynamic drag of a vehicle fluctuates over time due to repetitions of generation, growth, merging and disappearance of various sizes of vortices around it. These vortices are formed by flow separations, for which the longitudinal coherent vortices inside turbulent boundary layers on vehicle surfaces are presumably playing an important role.

The dynamics model and model-based controller (LQG servo controller) have been constructed to improve performance of diesel engine in transient condition. The input parameters of the model are fuel quantity of main injection, timing of main injection, fuel quantity of pilot injection, timing of pilot injection, external EGR ratio and boost pressure. The parameters that are succeeded between cycles to express transient condition are residual gas temperature and of residual oxygen. In the model, one cycle is discretized into 10 representative points. The precision of the accuracy of the model and the responsiveness of the controller were confirmed.

In this paper, a simplified prediction model for aiming to design an engine control system of Homogeneous Charge Compression Ignition (HCCI) engine has been developed. Developed HCCI engine model is for rebreathing concept and employs the discretized cycle concept to realize fast calculation speed. The ignition timings are predicted by Livengood-Wu integration combined with a function of ignition delay and the combustion durations are predicted from supplied fuel mass quantity. Maximum pressure and its phase are compared to experiments. In addition, for designing an HCCI engine, the models to predict appropriate operation conditions are considered.

To determine the auto-ignition and combustion mechanisms and the components of syngas that are applicable to homogeneous charge compression ignition (HCCI) engines, the combustion characteristics and the chemical reaction process in an HCCI engine were studied numerically and experimentally using mock syngas with various mixtures of the fuel components. The mock syngas consisted of hydrogen (H2) and carbon monoxide (CO) as the main combustible components, nitrogen (N2) and carbon dioxide (CO2) as incombustible components and a small amount of methane (CH4), assuming the composition of the gas was produced from wood by thermochemical conversion processes. The oxidation reaction process was analyzed numerically using CHEMKIN-PRO. Further experiments were conducted to investigate the validity of the calculated results. Primarily, the effects of hydrogen and carbon monoxide on auto-ignition and combustion were investigated.

This paper discusses research activities at the Technische Universität München on the HCCI combustion process, focusing on the development of a model-based control concept with pressure indication. As a first step sensitivity analyses have been carried out to investigate influences of different injection strategies on the combustion and emission characteristics. An optimal injection strategy has been determined and reasonable control variables and ranges corresponding to this strategy were defined. Comprehensive steady-state measurements have been conducted to detect the engine characteristics. In order to limit the experimental effort, principles of DoE (Design of Experiments) have been used to define a methodological approach in the planning of the measurements. Afterwards a multiple-input multiple-output engine model including boundary models for input settings has been designed out of the measurement results.

For the next stage of Homogeneous Charge Compression Ignition (HCCI) engine researches, the development of an engine controller, taking account of dynamics is required. The objective of this paper is to develop dynamic multi input and multi output HCCI engine models and a controller to deal with variable valve lift, variable valve phase, and fuel injection. First, a physical continuous model has been developed. This model mainly consists of air flow models, an ignition model, and a combustion and mechanical model of the engine. The flow models use a receiver model on volumetric elements such as an intake manifold and a valve flow model on throttling elements such as intake valves. Livengood-wu integration of Arrhenius function is used to predict ignition timing. The combustion duration is expressed as a function of ignition timings.

The ignition delay times of primary reference fuel (PRF) and toluene mixtures have been measured behind the reflected shock waves. The range of experiments covered combustion of fuel in diluted argon for stoichiometric mixtures, pressures of 2.5 atm, temperatures from 1200-1600 K, 0.4% of fuel concentration. The ignition delay times of n-heptane increased with the addition of toluene. However the ignition delay times of iso-octane decreased with the addition of toluene from 0 to 50% and increased from 50 to 100%. A detailed kinetic model with cross reactions considered in this study can not reproduce the trend of ignition delay times for iso-octane/toluene mixtures. From the reaction path analysis, it was suggested that cross reactions between alkenes and aromatics are required to account for these experimental results.

Velocity measurement of an intermittent high-speed flow inside a micro wave rotor cell was carried out using a laser Doppler anemometry (LDA). The cell is 3 × 3 mm rectangular tube, whose length is 42 mm. The pressure ratio and rotor speed of the wave rotor were set at 2.5 and 5,000 rpm, respectively. Ethanol droplets were seeded into the flow as scattering particles. By use of laser beam expanders, the probe volume of the LDA optics was minimized, and sub-millimeter special resolution is realized while a wide velocity range (-100 to 300 m/s) is kept. It is shown that the velocity histories at local positions inside the wave rotor cell can be obtained with the LDA optics. The rapid velocity increase and decrease, due to the primary and secondary shock waves, are observed, and the propagation speed of the shock waves was estimated. It is shown that the velocity profile inside the cell is flat and that the boundary layer thickness inside the cell is smaller than 0.5 mm.

Large Eddy Simulation (LES) with Smagorinsky model is sued to simulate the induction-compression processes of a motored engine within a cycle. A diesel engine constructed with swirl-generating port and dish-type combustion chamber is used as the model engine. For high Reynolds number flow, the wall-function fitted to generalized curvilinear coordinate is proposed in this paper in order to overcome the over-fine grids arrangement near wall region. In order to restrain the non-physical pressure oscillation, which is the fatal drawback in co-located grids layout used in the present study, the odd-even pressure coupling mode is developed. LES results are compared with PIV experiment. The most important result is that the curves of swirl number and turbulence intensity against crank angle are obtained. Swirl velocity is formed by tangent designed port, but is strengthened by the impingement of discharge onto piston surface.

Historically Diesel engines with turbocharger (TC) suffer so called “Turbo-Lag”, which presents deficiency in intake air-supply during the low engine speed stage. This insufficient air-supply causes emissions much higher than their normal operating conditions. For this a “Hybrid” supercharge-engine has been proposed [1], where a mechanically driven supercharger (SC) is used during the low engine speed zone. This paper proposes a new EGR (Exhaust Gas Return) system concept applicable to Diesel engines, which will achieve the compatibility to the stringent emission standard of USA in the year 2004, which is more stringent than EURO-3. S.P.Edwards et al [2] discussed some measures to clear EURO-3 values are discussed, but those, “D” and “E” in the Figure 1 are not possibly achievable in the near future. Therefore only EGR among those discussed in the paper is realistic.

To solve the pollutant emissions from a diesel engine, it seems quite effective to replace a diesel engine with a gasoline engine whose emission is less dirty. For this purpose it is required for a gasoline engine to improve the fuel consumption to the same level of a conventional diesel engine, so that the Miller system was applied to a gasoline engine. The Miller cycle gasoline engine equipped with rotary valves to control induced charge has an ability to vary the effective compression ratio, so that the better fuel economy is obtained due to the effects of both higher expansion ratio and decrease in pumping loss. 2.6 liter Miller cycle gasoline engine has a similar fuel consumption characteristic as the conventional 3.0 liter diesel engine. Although the output performance of the Miller cycle gasoline engine is inferior a little to that of the diesel engine, the emission characteristic of the Miller engine is far superior.

A Hybrid Exhaust Gas Recirculation (Hybrid EGR) is proposed. In this system the exhaust gas of a gasoline engine is mixed with the intake air of the diesel engine. The Hybrid EGR system eliminates the adverse effects of conventional diesel engine EGR systems on particulate formation, engine performance and durability. The application of a Hybrid EGR system to an experimental single cylinder diesel engine reduced NOx emissions to one-third the level produced by the same engine without EGR. These results were achieved with a Hybrid EGR dilution ratio of only 10 percent by volume without any particular increase in smoke emissions. Simulation results of a practical system application to motor vehicles are discussed. It is predicted that the new system will reduce vehicular diesel NOx emissions by one-half, without increasing the smoke level or adversely affecting fuel consumption.

Laser induced fluorescence (LIF) is a useful method for visualizing the distribution of the air-fuel ratio in the combustion chamber. The way this method is applied mainly depends on the fluorescent tracer used, such as biacetyl, toluene, various aldehydes, fluoranthene or diethylketone, among others. Gasoline strongly absorbs light in the UV region, for example, at the 248-nm wavelength of broadband KrF excimer laser radiation. Therefore, when using this type of laser, iso-octane is employed as the fuel because it is transparent to 248-nm UV light. However, since the distillation curves of iso-octane and gasoline are different, it can be expected that their vaporization characteristics in the intake port and cylinder would also be different. The aim of this study was to find a better fuel for use with LIF at a broadband wavelength of 248 nm. Three tasks were undertaken in this study.

This paper deals with a new type of Miller cycle engine which is installed with an intake control rotary valve, and presents the experimental investigation on the test engine which was undertaken to examine the capacity of supercharging as well as fuel economy in the application of the new system to small-sized gasoline engines. An experimental investigation on the test engine with some simple modification to a conventional engine revealed that the intake control rotary valve installation is quite effective to control the virtual compression ratio. It was ascertained by an external supercharging test that reduced compression ratio with constant expansion ratio allowed the test engine to obtain a considerably higher level of torque in the low engine speed range than had been attained in conventional supercharged engines without any increase in fuel consumption.