欧洲汽车动力系统多元化的发展趋势和展望

当前,全球能源结构处在变革时期,低碳和零碳化是包括汽车行业在内的所有经济运行和规划活动中的重中之重。汽车动力系统的能源呈现多元化的发展趋势,始于轻型车的电动化已成为不可逆转的总体方向,而氢时代在到来之前面临各种技术和非技术类等诸多问题的挑战。电动化带来的一个更为广泛应用的新技术是人工智能(AI),从而使得汽车动力系统逐步突破传统设计方法的局限得以适应更加复杂的环境条件并获得高效率。该文介绍欧洲汽车动力系统电动化和多元化的发展趋势,针对欧盟正在考虑中的电力合成燃料等问题并结合动力系统智能化等发展趋势,对欧洲汽车技术领域在2035年前的研发动向作出相关思考以及展望。

Numerical study of novel OME1-6 combustion mechanism and spray combustion at changed ambient environments

For a climate-neutral future mobility,the socalled e-fuels can play an essential part.Especially,oxygenated e-fuels containing oxygen in their chemical formula have the additional potential to burn with significantly lower soot levels.In particular,polyoxymethylene dimethyl ethers or oxymethylene ethers(PODEs or OMEs)do not contain carbon-carbon bonds,prohibiting the production of soot precursors like acetylene(C2H2).These properties make OMEs a highly interesting candidate for future climate-neutral compression-ignition engines.However,to fully leverage their potential,the auto-ignition process,flame propagation,and mixing regimes of the combustion need to be understood.To achieve this,efficient oxidation mechanisms suitable for computational fluid dynamics(CFD)calculations must be developed and validated.The present work aims to highlight the improvements made by developing an adapted oxidation mechanism for OME1-6 and introducing it into a validated spray combustion CFD model for OMEs.The simulations were conducted for single-and multi-injection patterns,changing ambient temperatures,and oxygen contents.The results were validated against high-pressure and high-temperature constantpressure chamber experiments.OH*-chemiluminescence measurements accomplished the characterization of the auto-ignition process.Both experiments and simulations were conducted for two different injectors.Significant improvements concerning the prediction of the ignition delay time were accomplished while also retaining an excellent agreement for the flame lift-off length.The spatial zones of high-temperature reaction activity were also affected by the adaption of the reaction kinetics.They showed a greater tendency to form OH*radicals within the center of the spray in accordance with the experiments.

Navigating the hydrogen prospect:A comprehensive review of sustainable source-based production technologies,transport solutions,advanced storage mechanisms,and CCUS integration

The review is a comprehensive discussion of current research advances,commercial scale developments,challenges,and techno-eco nomics for the entire H_(2) value chain,including production,mainly focusing on sustainable sources,storage,and transport.The challenges,advantages,and uses of H_(2) energy are included at length.Moreover,apart from the sustainable production approaches,the approaches and current developments for combating the carbon dioxide(CO_(2))emissions from existing H_(2) production facilities are highlighted in terms of ca rbon capture,utilization,and storage(CCUS).Concisely,the review discusses current material and recent technological adva ncements in developing pilot projects and large-scale establishments for viable and rapidly emerging sou rce-ba sed H_(2) productio n.Moreover,the review also aims to provide an in-depthdiscussion and explore current developments based on the advantages of H_(2) energy in terms of its utilization,based on its high energy density,and its ability to be used as a feedstock and fuel.On the other hand,the challenges of H_(2) are also elabo rated.Next,the role of CCUS in a carbon-neutral economy and value chain for minimization of emissions from existing facilities is thoroughly deliberated,and the recent commercial-scale implementation of CCUS technologies is highlighted.Extending the utilization and recycling of captured CO_(2) emissions along with H_(2) to produce e-fuels in terms of current advances is detailed in this review.Fu rthermore,the most applicable,efficient,a nd develo ping approaches are discussed for physical and chemical H_(2) storage,considering recent la rge-scale implementations of liquid carriers and liquid organic hydrogen carriers as storage options.Lastly,the review elaborates on recent insights into advances in H_(2) transport infrastructure,including compressed and liquid H_(2) delivery via roads,ships,pipelines,and flight cargo.The review gives precise insights into the recent scenario through an elaborated conclusion of each discussion topic separately and a discussion of future perspectives.The current review will help researchers to fully understand the ongoing research advancements and challenges in the H_(2) value chain for formulating new solutions for sustainable H_(2) production,alo ng with focusing on suitable approaches for its storage and tra nsport to make the production and utilization of H_(2) applicable on a large scale.

Mathematical modeling of fuel cells fed with an electrically rechargeable liquid fuel

Lately,utilizing a novel electrically rechargeable liquid fuel(e-fuel),a fuel cell has been designed and fabricated,which is demonstrated to achieve a much better performance than alcoholic liquid fuel cells do.However,its current performance,which thus hampers its wide application,demands further improvement to meet up with industrial requirement.Therefore,to attain a better performance for this system,an in-depth understanding of the complex physical and chemical processes within this fuel cell is essential.To this end,in this work,a two-dimensional transient model has been developed to gain an extensive knowledge of a passive e-fuel cell and analyze the major factors limiting its performance.The effects of various structural parameters and operating conditions are studied to identify the underlying performance-limiting factors,where deficient mass transport is found to be one of the major causes.The increment of anode porosity and thickness are found to be effective methods of improving the cell performance.This study therefore provides insights on achieving further per-formance advancement of the fuel cell in the future.

A novel energy storage system incorporating electrically rechargeable liquid fuels as the storage medium

We propose a novel concept of energy storage that incorporates electrically rechargeable liquid fuels made of electroactive species, known as e-fuels, as the storage medium. This e-fuel energy storage system comprises an e-fuel charger and an e-fuel cell. The e-fuel charger electrically charges e-fuels, while the efuel cell subsequently generates electricity using charged e-fuels whenever and wherever on demand.The e-fuel energy storage system possesses all the advantages of conventional hydrogen storage systems,but unlike hydrogen, liquid e-fuels are as easy and safe to store and transport as gasoline. The potential efuel candidates have been identified to include inorganic electroactive materials, organic electroactive materials, and suspension of solid electroactive materials. In this work, we demonstrate an example efuel energy storage system for large-scale energy storage using inorganic e-fuels composed of V^(2+)/V^(3+) and VO_2^+/VO_2^+ redox couples, and compare the performance of the e-fuel energy storage system with that of existing technologies. Results show that our e-fuel charger achieves a charge efficiency of as high as～94%, while the e-fuel cell is capable of delivering a peak power density of 3.4 W cm^(-2), which is 1.7 times higher than that of hydrogen fuel cells. More excitingly, the e-fuel energy storage system exhibits a round-trip efficiency of 80.0% and an electrolyte utilization of 83.0% at an ultra-high discharge current density of 1,000 mA cm^(-2), which are 19.9% and 67.3% higher than those of conventional vanadium redox flow batteries. This unprecedented performance allows a 27.0% reduction in the capital cost of the e-fuel energy storage system compared with that of vanadium redox flow batteries.

Beyond fossil:the synthetic fuel surge for a green-energy resurgence

This review offers a comprehensive overview of synthetic fuels as promising alternatives to conventional fossil fuels.The carbon-neutral potential of synthetic fuels when produced using renewable energy and captured CO_(2),offering significant opportunities to mitigate CO_(2) emissions,is discussed.Moreover,the efficiency of synthetic fuels is presented,as they do not require dedicated agricultural land or substantial water resources,addressing concerns related to the land-use change and water scarcity associated with traditional biofuels.The economic viability of synthetic fuels is explored,highlighting the advancements in technology and decreased renewable-energy costs,coupled with their independence from food crops,mitigating concerns about potential impacts on food prices.Major investments by industry leaders such as Porsche,Highly Innovative Fuels Global,and ExxonMobil,totalling$1 billion,aimed at achieving an annual production of 550 million litres by 2026,are covered in detail.This study is further extended by emphasizing the scalability of synthetic fuel production through modular processes,enabling tailored facilities to meet regional demands and contribute to a decentralized and resilient energy infrastructure.Additionally,the‘drop-in’nature of synthetic fuels that are seamlessly compatible with existing fuel storage,pipelines,and pumps,facilitating a smooth transition without requiring extensive infrastructure changes,is highlighted.Challenges such as the current high cost of synthetic fuel production are acknow-ledged,necessitating supportive government policies and incentives for widespread adoption.Overall,synthetic fuels have emerged as promising contenders in the pursuit of sustainable and adaptable energy solutions,with tangible benefits for the environment,economy,and existing energy infrastructure.