Renewable Energy最新文献_第7页

Ultra-broadband absorber and perfect thermal emitter for high-efficiency solar energy absorption and conversion 超宽带吸收器和完美热发射器，实现高效太阳能吸收和转换

IF 9 1区工程技术 Q1 ENERGY & FUELS

Renewable Energy

Pub Date : 2024-11-05 DOI: 10.1016/j.renene.2024.121818

Haining Yuan , Yingting Yi , Qianju Song , Zao Yi , Tangyou Sun , Chaojun Tang , Qingdong Zeng , Shubo Cheng , Pinghui Wu

This study proposes a pyramid-shaped solar absorber designed with multi-layered Ti-SiO₂ ring stacked. The structure achieves an average absorption efficiency of 98.03 % over the range of 280–4000 nm, and under AM1.5 spectral conditions, the weighted average absorption efficiency reaches 97.66 %, the bandwidth with an absorption efficiency greater than 90 % reaches 3750 nm. To explore the reason for achieving ultra-broadband absorption with this structure, the electromagnetic field distribution at three absorption peaks was calculated. The results revealed that the resonance between the polarization direction of the three-layer circular ring stacked structure and the plasmon resonance at the junction of Ti and SiO₂ contribute to the model's capability for ultra-broadband high-efficiency absorption. At the same time, the thermal emissivity of the structure was calculated at high temperatures of 1000 K and 2000 K, both exceeding 97 %. Furthermore, due to the fully symmetrical design, the absorber is polarization-independent. It was found through calculations that whether in TM mode or TE mode, as the incident angle varies from 0° to 60°, the average absorption efficiency of the absorber changes only by 11.16 %, thereby verifying the structure's excellent insensitivity to incident light angles. In summary, all these characteristics indicate that the model has excellent application prospects in fields such as solar energy collection and photothermal conversion.

本研究提出了一种由多层 Ti-SiO2 环形堆叠设计而成的金字塔形太阳能吸收器。该结构在 280-4000 nm 范围内的平均吸收效率达到 98.03 %，在 AM1.5 光谱条件下，加权平均吸收效率达到 97.66 %，吸收效率大于 90 % 的带宽达到 3750 nm。为了探究该结构实现超宽带吸收的原因，计算了三个吸收峰的电磁场分布。结果表明，三层圆环堆叠结构极化方向之间的共振以及 Ti 和 SiO2 交界处的等离子体共振有助于该模型实现超宽带高效吸收。同时，该结构在 1000 K 和 2000 K 高温下的热发射率均超过 97%。此外，由于采用了完全对称的设计，该吸收器与极化无关。通过计算发现，无论是在 TM 模式还是 TE 模式下，当入射角度从 0° 变化到 60° 时，吸收器的平均吸收效率仅变化 11.16%，从而验证了该结构对入射光角度的卓越不敏感性。总之，所有这些特点都表明，该模型在太阳能收集和光热转换等领域具有良好的应用前景。

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引用次数: 0

Design and performance analysis of a novel downhole heat exchanger for deep geothermal wells: Experimental and field tests 用于深层地热井的新型井下热交换器的设计和性能分析：实验和现场测试

IF 9 1区工程技术 Q1 ENERGY & FUELS

Renewable Energy

Pub Date : 2024-11-05 DOI: 10.1016/j.renene.2024.121779

Dongxi Liu , Di Gu , Wei Zhang , Shuntao Hu , Maoqin Hu , Tianyi Sun , Chuanshan Dai

This study addresses the challenge of "extracting heat without extracting water" in geothermal energy systems, which is a key requirement for sustainable resource utilization. A novel downhole heat exchanger (NDHE) was designed to increase the heat exchange efficiency in compact geothermal single-well systems. This research employed theoretical analysis, experimental studies, and field tests. The heat exchanger, which incorporates a single-pass flow for geothermal water and a dual-pass flow for ground loop water, achieved a heat transfer coefficient of 2200–3200 W/(m²·K) and a maximum heat extraction power of 32 kW under laboratory conditions. In field applications, the system demonstrated a heat extraction power of 185 kW—38–58 % higher than that of existing technologies—sufficient to meet the 155 kW heating demand for buildings. Under full load, the predicted maximum capacity reached 555 kW, more than quadrupling the performance of current single-well systems. This innovative heat exchanger significantly enhances both heat extraction efficiency and scalability, paving the way for broader adoption of geothermal energy technologies.

本研究解决了地热能源系统中 "抽热不抽水 "的难题，这是可持续资源利用的关键要求。为提高紧凑型地热单井系统的热交换效率，设计了一种新型井下热交换器（NDHE）。这项研究采用了理论分析、实验研究和现场测试。该热交换器采用了地热水单通流和地面循环水双通流，在实验室条件下，热传导系数达到 2200-3200 W/（m2-K），最大热提取功率为 32 kW。在实地应用中，该系统的汲取热量功率为 185 kW，比现有技术高出 38-58%，足以满足建筑物 155 kW 的供热需求。在满负荷情况下，预计最大功率可达 555 千瓦，是目前单井系统性能的四倍多。这种创新的热交换器大大提高了热提取效率和可扩展性，为地热能源技术的广泛应用铺平了道路。

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引用次数: 0

Isopropanol-Acetone-Hydrogen chemical heat pumps for improved heat recovery from geothermal resources, A case study in China 异丙醇-丙酮-氢化学热泵用于改善地热资源的热回收，中国案例研究

IF 9 1区工程技术 Q1 ENERGY & FUELS

Renewable Energy

Pub Date : 2024-11-05 DOI: 10.1016/j.renene.2024.121730

Zhengguang Liu , Lili Wang , Xiaohu Yang , Masoud Babaei

This study focuses on geothermal energy utilization through multi-objective optimization of Isopropanol-Acetone-Hydrogen chemical heat pump (IAH-CHP). In this paper, IAH-CHP coupled with medium-low temperature geothermal heat source simulation was constructed. China, the world’s largest carbon emitter, was used as a case study to highlight environmental benefits. Comparative analysis was conducted between carbon emissions and investment of chemical heat pumps with other common heating equipment in different buildings. The results show IAH-CHP system has higher initial investment costs, however, their CO

_{2}

emissions are significantly lower. The results of multi-objective analysis demonstrate the system can operate under a Pareto (multi-objective) optimal scheme. Under this plan, the levelized cost of heat (LCOH) is only 0.12 USD/kJ, and the carbon emissions are as low as 4.97 tons/year with a coefficient of performance (COP) of 7.4. Compared with a single-objective optimal solution, 8.12 tons of carbon emissions and LCOH of 0.15 USD/kJ could be achieved. Applying IAH-CHP system to China to replace original coal-fired heating solution can achieve annual carbon emission reduction of more than 5 million tons in areas with medium and low temperature heat sources.

本研究通过对异丙醇-丙酮-氢化学热泵（IAH-CHP）进行多目标优化，重点关注地热能的利用。本文构建了 IAH-CHP 与中低温地热热源的耦合模拟。中国是世界上最大的碳排放国，本文以中国为案例，突出环境效益。对比分析了化学热泵与其他常见供热设备在不同建筑中的碳排放量和投资。结果显示，IAH-CHP 系统的初始投资成本较高，但其二氧化碳排放量却明显较低。多目标分析结果表明，该系统可在帕累托（多目标）最优方案下运行。在该方案下，热量平准化成本（LCOH）仅为 0.12 美元/千焦，碳排放量低至 4.97 吨/年，性能系数（COP）为 7.4。与单目标最优解相比，可实现 8.12 吨的碳排放量和 0.15 美元/千焦的 LCOH。在中国应用 IAH-CHP 系统取代原有的燃煤供热方案，可在中低温热源地区实现年碳减排量超过 500 万吨。

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引用次数: 0

Long-term emission demonstration using pretreated urban non-woody biomass residues as fuel for small scale boilers 使用预处理城市非木质生物质残渣作为小型锅炉燃料的长期排放示范

IF 9 1区工程技术 Q1 ENERGY & FUELS

Renewable Energy

Pub Date : 2024-11-05 DOI: 10.1016/j.renene.2024.121815

Roman Adam , Thomas Zeng , Lisa Röver , Philipp Schneider , Hans Werner , Thomas Birnbaum , Volker Lenz

There is currently a lack of non-woody biogenic solid biofuels to replace fossil fuels to expand renewable heat energy due to their combustion-critical behavior (slagging and emissions). For this reason, this study demonstrates a best practice under which non-woody solid biofuels can be put into practice. For this demonstration, a homogeneous non-woody solid biofuel was produced from urban park foliage in accordance with ISO 17225–6:2021 on industrial scale (>50 t). Long-term combustion tests were performed in a small-scale combustion system (80 kW) under field test conditions. Compliance with all emission thresholds of the legal framework was demonstrated (Carbon monoxide (CO): 44.9 mg/m³, Total particulate matter (TPM): 11.9 mg/m³, Nitrogen oxides (NO_x): 279.6 mg/m³, Polychlorinated dibenzodioxins and dibenzofurans + Dioxin-like polychlorinated biphenyls (PCDD/F + dl-PCB): 0.01 ng/m³ and Benzo[a]pyrene (B(a)P): 7.3*10⁻⁶ mg/m³). Additionally, nutrient cycles can be closed by applying the bottom ash as soil fertilizer additive. Based on the study, greenhouse gas-neutral fuels from non-woody biomass residues for comparable applications can be produced based on the demonstration.

由于非木质生物固体生物燃料在燃烧过程中的关键行为（结渣和排放），目前还缺乏非木质生物固体生物燃料来替代化石燃料，以扩大可再生热能。因此，本研究展示了一种可将非木质固体生物燃料付诸实践的最佳做法。为了进行示范，我们按照 ISO 17225-6:2021 标准，以工业规模（50 吨）从城市公园落叶中生产出均质非木质固体生物燃料。在现场测试条件下，在小型燃烧系统（80 千瓦）中进行了长期燃烧测试。结果表明符合法律规定的所有排放阈值（一氧化碳 (CO)：44.9 mg/m³、总颗粒物 (TPM)：11.9 mg/m³、氮氧化物 (NOx)：279.6 mg/m³、多氯二苯并二恶英和二苯并呋喃 + 二恶英类多氯联苯 (PCDD/F + dl-PCB)：0.01 ng/m³ 和苯并[a]芘 (B(a)P)：7.3*10-6 mg/m³）。此外，将底灰作土壤肥料添加剂还可封闭养分循环。根据这项研究，利用非木质生物质残渣生产温室气体中性燃料的示范应用具有可比性。

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引用次数: 0

Reduction short-chain volatile fatty acids and CO2 into alcohols in microbial electrosynthesis system 在微生物电合成系统中将短链挥发性脂肪酸和二氧化碳还原为酒精

IF 9 1区工程技术 Q1 ENERGY & FUELS

Renewable Energy

Pub Date : 2024-11-05 DOI: 10.1016/j.renene.2024.121751

Wenjuan Chu , Zhiyong Wu , Xiaohu Li , Merlin Alvarado-Morales , Dawei Liang

Microbial electrosynthesis system (MES) is an attractive strategy for converting CO₂ into value-added chemicals and biofuels. In this work, it is for the first time demonstrates the feasibility of producing biofuels (eg., ethanol and butanol) from CO₂ and volatile fatty acids (eg. acetic acid and butyric acid) by utilizing Clostridium ljungdahlii ERI-2 as biocatalyst in MES. The highest ethanol and butanol concentration of 12.52 ± 0.57 and 5.85 ± 0.78 mM are obtained at −0.9 V (vs Ag/AgCl) cathode potential, respectively. Furthermore, the trace elements content in growing medium is optimized to improve the production rate of ethanol from acetic acid/CO₂ and butanol from butyric acid/CO₂. Adding suitable Ni²⁺ and WO₄²⁻ in the growing medium resulted in the maximum ethanol and butanol production can be increased 43.3 ± 3.2 % and 32.1 ± 3.5 %, respectively. The analysis of redox cofactor concentration indicates that the NADH is the main reducing force for the improvement of alcohols production. Based on these results, strategies for further improvement of CO₂ to alcohols conversion can be formulated.

微生物电合成系统（MES）是将二氧化碳转化为高附加值化学品和生物燃料的一种极具吸引力的策略。本研究首次证明了在微生物电合成系统中利用 ljungdahlii ERI-2 梭菌作为生物催化剂从二氧化碳和挥发性脂肪酸（如乙酸和丁酸）生产生物燃料（如乙醇和丁醇）的可行性。在阴极电位为-0.9 V（相对于 Ag/AgCl）时，乙醇和丁醇的最高浓度分别为 12.52 ± 0.57 mM 和 5.85 ± 0.78 mM。此外，还优化了生长培养基中的微量元素含量，以提高乙酸/CO2 产生乙醇和丁酸/CO2 产生丁醇的生产率。在生长培养基中添加适当的 Ni2+ 和 WO42- 可使乙醇和丁醇产量分别提高 43.3 ± 3.2 % 和 32.1 ± 3.5 %。氧化还原辅助因子浓度分析表明，NADH 是提高酒精产量的主要还原力。根据这些结果，可以制定进一步提高二氧化碳到醇类转化率的策略。

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引用次数: 0

Acid-catalyzed co-hydrothermal carbonization of sewage sludge and mixed straws to produce high-quality solid fuel 酸催化污水污泥和混合秸秆的共水热碳化以生产优质固体燃料

IF 9 1区工程技术 Q1 ENERGY & FUELS

Renewable Energy

Pub Date : 2024-11-05 DOI: 10.1016/j.renene.2024.121820

Xiaoguang Liu , Jinna Gu , Yongdong Chen , Hong Wang , Chiqian Zhang , Shijie Yuan , Xiaohu Dai

To improve the hydrochar fuel quality, acid-catalyzed co-hydrothermal carbonization (co-HTC) of sewage sludge with mixed straws were performed at 220 °C. The impacts of mixing ratio (1:0, 1:3, 1:1, 3:1, and 0:1) and solvent (0.5 M HCl or dionized water) on hydrochar quality were assessed. The acid-catalyzed co-HTC increased the higher heating value and fuel ratio of the hydrochar by decreasing the H/C atomic ratio and increasing the O/C atomic ratio. The devolatilization index (D_i) and combustibility index (S) of the hydrochar from co-HTC at a sludge-to-straws dry-mass ratio of 1:1 reached 64.6 and 26.8 (10⁻⁸ wt%² min⁻² K⁻³), respectively, which was over three times and 2.5 times that from sludge. D_i was affected by the surface functional groups, whereas S was related to the chemical composition and fuel properties. Less energy is required after acid-catalyzed co-HTC for both pyrolysis and combustion processes, because of the increase in O/C atomic ratio. This study not only demonstrates the yields and quality of the hydrochar in response to the variation of mixing ratio and solvent, but also uncovers the relationship between hydrochar quality and pyrolysis/combustion performance, thereby providing valuable information for optimizing the acid-catalyzed co-HTC process.

为了提高水炭燃料的质量，在220 °C下对污水污泥和混合秸秆进行了酸催化共热碳化（co-HTC）。评估了混合比例（1:0、1:3、1:1、3:1 和 0:1）和溶剂（0.5 M HCl 或电离水）对水炭质量的影响。酸催化共 HTC 通过降低 H/C 原子比和提高 O/C 原子比，提高了水碳的热值和燃料比。在污泥与秸秆干物质比为 1:1 的条件下，共热催化技术产生的水炭的脱灰指数（Di）和可燃指数（S）分别达到 64.6 和 26.8（10-8 wt%2 min-2 K-3），分别是污泥的 3 倍和 2.5 倍以上。Di 受表面官能团的影响，而 S 则与化学成分和燃料特性有关。由于 O/C 原子比的增加，酸催化共 HTC 后热解和燃烧过程所需的能量都减少了。这项研究不仅证明了混合比和溶剂变化对水炭产量和质量的影响，还揭示了水炭质量与热解/燃烧性能之间的关系，从而为优化酸催化共热碳化工艺提供了有价值的信息。

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引用次数: 0

A feedback linearization sliding mode decoupling and fuzzy anti-surge compensation based coordinated control approach for PEMFC air supply system 基于反馈线性化滑模解耦和模糊防喘振补偿的 PEMFC 供气系统协调控制方法

IF 9 1区工程技术 Q1 ENERGY & FUELS

Renewable Energy

Pub Date : 2024-11-05 DOI: 10.1016/j.renene.2024.121760

Chao Peng , Chuan Xie , Jianxiao Zou , Xinyan Jiang , Yun Zhu

With the application of proton exchange membrane fuel cell (PEMFC) in the field of transportation and energy, the requirements for air flow and pressure tracking performance, efficiency and stability of PEMFC air supply system become higher and higher. To improve PEMFC cathode air flow and pressure control performance under load variation and avoid surge of air compressor, a novel feedback linearization sliding mode decoupling and fuzzy anti-surge compensation based coordinated control approach is proposed. Firstly, optimal references of oxygen excess ratio (OER) and cathode air pressure under different load are calculated based on net output power of PEMFC system analysis. Then, an extended state observer is designed to estimate the cathode air pressure and flow in real time, a feedback linearization sliding mode based decoupling controller is designed to enhance OER and air pressure tracking control performance and robustness. Considering on the operating trajectory and surge line of air compressor, a fuzzy logic based anti-surge compensator is designed to prevent air compressor from surge by compensating both air flow and pressure simultaneously. The proposed control approach is implemented in PEMFC air supply control experiments and the results demonstrates its effectiveness.

随着质子交换膜燃料电池（PEMFC）在交通和能源领域的应用，对 PEMFC 供气系统的气流和压力跟踪性能、效率和稳定性的要求越来越高。为改善 PEMFC 负载变化下阴极空气流量和压力控制性能，避免空气压缩机喘振，提出了一种新颖的基于反馈线性化滑模解耦和模糊防喘振补偿的协调控制方法。首先，根据 PEMFC 系统的净输出功率分析，计算出不同负载下氧气过剩率（OER）和阴极气压的最佳参考值。然后，设计了一个扩展状态观测器来实时估计阴极气压和流量，并设计了一个基于反馈线性化滑动模式的解耦控制器，以提高 OER 和气压跟踪控制性能和鲁棒性。考虑到空气压缩机的运行轨迹和浪涌线，设计了一种基于模糊逻辑的防浪涌补偿器，通过同时补偿空气流量和压力来防止空气压缩机浪涌。在 PEMFC 供气控制实验中实施了所提出的控制方法，结果证明了其有效性。

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引用次数: 0

RBFNN based fixed time sliding mode control for PEMFC air supply system with input delay 基于 RBFNN 的固定时间滑动模式控制，适用于带输入延迟的 PEMFC 供气系统

IF 9 1区工程技术 Q1 ENERGY & FUELS

Renewable Energy

Pub Date : 2024-11-05 DOI: 10.1016/j.renene.2024.121772

Mehran Derakhshannia, Seyyed Sajjad Moosapour

Ensuring rapid regulation of the oxygen excess ratio (OER) in proton exchange membrane fuel cells (PEMFC) during load changes is an important challenge. In this paper, fixed time sliding mode control of a PEMFC with input delay has been investigated. First, a simplified fourth-order nonlinear dynamical model with input disturbance and input delay is considered and a cascade structure is selected for the control design. A radial basis function neural network (RBFNN) is designed to estimate the input disturbance. To achieve precise estimation, a Cuckoo Search Algorithm is utilized to calculate the parameters of the RBFNN. Then, a new sliding mode controller is proposed for trajectory tracking within a fixed time. To ensure the effectiveness of the proposed controller, the fixed time convergence of both sliding and reaching phases is investigated and proven. Finally, a robust prediction based sliding mode control is designed for the PEMFC system that by incorporating the disturbance estimation, can eliminate the effect of input delay. The effectiveness and robustness of the proposed controller are validated via comparative simulations. It is noteworthy that this is the first study to propose predictor based control for input delay PEMFCs.

确保质子交换膜燃料电池（PEMFC）在负载变化时快速调节氧过剩率（OER）是一项重要挑战。本文研究了具有输入延迟的质子交换膜燃料电池的定时滑动模式控制。首先，考虑了带有输入干扰和输入延迟的简化四阶非线性动力学模型，并选择了级联结构进行控制设计。设计了一个径向基函数神经网络（RBFNN）来估计输入干扰。为实现精确估计，利用布谷鸟搜索算法计算 RBFNN 的参数。然后，提出了一种新的滑模控制器，用于在固定时间内进行轨迹跟踪。为确保所提控制器的有效性，研究并证明了滑动和到达阶段的固定时间收敛性。最后，为 PEMFC 系统设计了一种基于鲁棒预测的滑动模态控制，该控制结合了干扰估计，可以消除输入延迟的影响。通过对比模拟，验证了所提控制器的有效性和鲁棒性。值得注意的是，这是首次针对输入延迟 PEMFC 提出基于预测器控制的研究。

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引用次数: 0

Study on improving heat extraction capacity of borehole heat exchanger by forced convection of groundwater 利用地下水强制对流提高钻孔热交换器汲取热量能力的研究

IF 9 1区工程技术 Q1 ENERGY & FUELS

Renewable Energy

Pub Date : 2024-11-04 DOI: 10.1016/j.renene.2024.121809

Yuzhe Jia, Guanghui Zhao, Tao Liu, Peng Li, Zhifeng He, Zheng Liang

Borehole Heat Exchangers (BHEs) has the advantage of "extracting heat without extracting groundwater". Its main drawback is low heat extraction power. Aiming at developing medium-deep hydrothermal geothermal resources, a Branch Well Reinforced Coaxial Borehole Heat Exchanger (BWR-CBHE) is proposed firstly. An assisted circulation loop formed by the wellbore and geothermal reservoir is created through drilling branch well and installing electric submersible pump (ESP). By driving the forced convection of groundwater within the assisted circulation loop, heat extraction capacity of the CBHE is enhanced. Then, a numerical model of the BWR-CBHE is established. The main circulation of the working fluid within the CBHE is coupled with the assisted circulation of groundwater, and the heat extraction performance of the BWR-CBHE is calculated. Under the conditions studied in this paper, the net heat extraction power (after deducting the energy consumption of the ESP) of the BWR-CBHE is 6.09 times higher than that of conventional CBHEs. Finally, impacts of parameters, including working fluid, branch well, ESP and formation, on the heat extraction capacity of the BWR-CBHE are discussed. The heat extraction power of the BWR-CBHE is increased significantly without extracting groundwater, which provides a new approach for the development of BHEs.

钻孔热交换器（BHE）具有 "无需抽取地下水即可提取热量 "的优点。其主要缺点是采热效率低。针对中深层热液地热资源的开发，首先提出了一种支井强化同轴井眼换热器（BWR-CBHE）。通过钻探分支井和安装电潜泵（ESP），在井筒和地热储层之间形成一个辅助循环回路。通过推动辅助循环环路内地下水的强制对流，CBHE 的汲取热量能力得以提高。然后，建立了 BWR-CBHE 的数值模型。将 CBHE 内工作流体的主循环与地下水的辅助循环耦合，计算出 BWR-CBHE 的萃取热性能。在本文研究的条件下，BWR-CBHE 的净萃取热功率（扣除静电除尘器能耗后）是传统 CBHE 的 6.09 倍。最后，讨论了工作液、分支井、静电除尘器和地层等参数对 BWR-CBHE 热提取能力的影响。在不抽取地下水的情况下，BWR-CBHE 的汲取热量能力显著提高，这为 BHE 的开发提供了一种新方法。

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引用次数: 0

Effects of isopropanol-butanol-ethanol on the performance, combustion and emission characteristics of a diesel-methanol dual-fuel engine 异丙醇-丁醇-乙醇对柴油-甲醇双燃料发动机性能、燃烧和排放特性的影响

IF 9 1区工程技术 Q1 ENERGY & FUELS

Renewable Energy

Pub Date : 2024-11-02 DOI: 10.1016/j.renene.2024.121790

Gang Li , Jinhai Wang , Kaijie Li , Ke Yang , Weiqiang Han , Songfeng Li

Both diesel-methanol dual-fuel (DMDF) combustion and the addition of isopropanol-butanol-methanol (IBE) into diesel are capable of reducing the fossil fuel usage and soot emissions of diesel engines, but few of studies focused on combining the advantages of these two methods. Thereby, diesel containing 10 %, 20 % and 30 % of IBE by volume were utilized as pilot fuel in this study to investigate how the addition of IBE into diesel affects the performance, combustion and emissions of the DMDF engine. Experiments were performed at the engine load of 20 %, 40 % and 60 % with the engine speed fixed at 1400r/min. The results show that at most test conditions, the brake thermal efficiency of the DMDF engine only suffers a slightly drop while the soot emissions greatly reduce when IBE is blended into the pilot fuel diesel. Moreover, the deterioration of CO, HC and NO_x emissions of DMDF engine can be significantly improved by blending no more than 20 % vol. IBE into the pilot fuel diesel. Additionally, with the volume ratio of IBE into the pilot fuel diesel increases to 30 %, the soot emissions of the DMDF engine can be further reduced at the costs of engine performance deteriorates and CO, HC, NO_x emissions increase. Although the deterioration of the engine performance caused by the addition of IBE into the pilot fuel diesel can be mitigated by increasing the methanol flow rate, NO_x emissions increase significantly.

柴油-甲醇双燃料（DMDF）燃烧和在柴油中添加异丙醇-丁醇-甲醇（IBE）都能减少柴油发动机的化石燃料用量和烟尘排放，但很少有研究侧重于将这两种方法的优势结合起来。因此，本研究将体积分数分别为 10%、20% 和 30% 的 IBE 柴油作为试验燃料，以研究在柴油中添加 IBE 如何影响 DMDF 发动机的性能、燃烧和排放。实验在发动机负荷为 20%、40% 和 60%、转速为 1400r/min 的条件下进行。结果表明，在大多数试验条件下，DMDF 发动机的制动热效率仅略有下降，而在先导燃料柴油中掺入 IBE 后，烟尘排放量大大减少。此外，在先导燃料柴油中掺入不超过 20% 体积比的 IBE 后，DMDF 发动机的 CO、HC 和 NOx 排放劣化情况得到明显改善。此外，随着 IBE 在先导燃料柴油中的体积比增加到 30%，DMDF 发动机的烟尘排放可以进一步减少，但代价是发动机性能恶化，CO、HC 和 NOx 排放增加。虽然通过增加甲醇流量可以缓解在先导燃料柴油中添加 IBE 导致的发动机性能下降，但氮氧化物排放量却显著增加。

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引用次数: 0