Journal of Supercritical Fluids最新文献_第9页

Solubility of ethenzamide and 2-chloro-4-nitrobenzoic acid in supercritical carbon dioxide from experiments and thermodynamic models 乙酰胺和2-氯-4-硝基苯甲酸在超临界二氧化碳中的溶解度的实验和热力学模型

IF 4.4 3区工程技术 Q2 CHEMISTRY, PHYSICAL

Journal of Supercritical Fluids

Pub Date : 2025-09-19 DOI: 10.1016/j.supflu.2025.106790

Yung-Chun Yang , Shih-Yu Chang , Yu-Ming Chen , Chie-Shaan Su , Chieh-Ming Hsieh

The solubility of solid solutes in supercritical carbon dioxide (scCO₂) is critical for crystal engineering and pharmaceutical formulation. In this study, the solubility of ethenzamide and 2-chloro-4-nitrobenzoic acid in scCO₂ was measured for the first time using a high-pressure semi-flow apparatus at 308.2 K, 318.2 K, and 328.2 K over a pressure range of 10 MPa to 22 MPa. The solubility of ethenzamide ranged from 1.09 × 10⁻⁵ to 3.24 × 10⁻⁴, and that of 2-chloro-4-nitrobenzoic acid from 3.88 × 10⁻⁶ to 2.07 × 10⁻⁴ (in mole fraction). Four semi-empirical models [Chrastil, Bartle, Mendez-Santiago & Teja (MST), and Kumar & Johnston (K-J)] were used to correlate the experimental data, yielding average absolute relative deviations (AARD) of 2.17–7.10 % for ethenzamide and 4.00–5.99 % for 2-chloro-4-nitrobenzoic acid, confirming the reliability of the measured solubility data. The validated data were further used to evaluate three thermodynamic approaches based on the Peng–Robinson equation of state (PR EOS). Among them, PR+VDW and PR+MHV1+Wilson achieved AARD values of 4.92 % and 8.97 % for ethenzamide, and 3.81 % and 8.64 % for 2-chloro-4-nitrobenzoic acid, respectively. The PR EOS couple with the COSMO-SAC model, implemented via the MHV1 mixing rule, provided good solubility predictions (AARD values of 33.98 % for ethenzamide and 6.30 % for 2-chloro-4-nitrobenzoic acid) without the need for parameter fitting.

固体溶质在超临界二氧化碳（scCO2）中的溶解度对晶体工程和药物配方至关重要。本研究首次采用高压半流动装置，在308.2 K、318.2 K和328.2 K条件下，在10 MPa至22 MPa的压力范围内，测定了乙酰胺和2-氯-4-硝基苯甲酸在scCO2中的溶解度。乙酰胺的溶解度范围为1.09 × 10−5 ~ 3.24 × 10−4,2-氯-4-硝基苯甲酸的溶解度范围为3.88 × 10−6 ~ 2.07 × 10−4（摩尔分数）。采用四个半经验模型[Chrastil， Bartle, Mendez-Santiago & Teja （MST）和Kumar &； Johnston (K-J)]对实验数据进行关联，得到乙酰胺的平均绝对相对偏差（AARD）为2.17-7.10 %，2-氯-4-硝基苯甲酸的平均绝对相对偏差（AARD）为4.00-5.99 %，证实了测量溶解度数据的可靠性。利用验证的数据进一步评价了基于Peng-Robinson状态方程（PR EOS）的三种热力学方法。其中，PR+VDW和PR+MHV1+Wilson对乙酰胺的AARD值分别为4.92 %和8.97 %，对2-氯-4-硝基苯甲酸的AARD值分别为3.81 %和8.64 %。通过MHV1混合规则实现的PR - EOS偶联cosmos - sac模型提供了良好的溶解度预测（乙酰胺的AARD值为33.98 %，2-氯-4-硝基苯甲酸的AARD值为6.30 %），无需参数拟合。

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引用次数: 0

Synergistic shrinkage control in supercritical CO2 foamed TPU systems via matrix strength modulation and nitrogen introduction 通过基质强度调节和氮气引入控制超临界CO2发泡TPU系统的协同收缩

IF 4.4 3区工程技术 Q2 CHEMISTRY, PHYSICAL

Journal of Supercritical Fluids

Pub Date : 2025-09-18 DOI: 10.1016/j.supflu.2025.106789

Huazhen Jiang, Panfeng Shao, Xia Liao

Thermoplastic polyurethane (TPU) foam has been applied widely in footwear, medical treatment, automotive, packaging, transportation, aerospace, etc. due to excellent properties such as elasticity, high impact strength, low temperature resistance. However, the significant shrinkage of TPU foam prepared by supercritical carbon dioxide (CO₂) imposes a limitation on its wider application. In this study, TPU with a low hardness which is favorable for high expansion ratio was used as the matrix and TPU foams prepared by two approaches was investigated: regulating hardness and crystallinity by incorporating high hardness TPU, as well as, foaming with mixture blowing agents or re-foaming with N₂. The results showed that the shrinkage behavior of TPU foam could be inhibited by regulating its hardness and crystallinity behavior. Furthermore, the final expansion ratio was improved significantly by re-foaming with N₂ in comparison to foaming with mixture blowing agent. It was ascertained that TPU foams first foamed with CO₂ and re-foamed with N₂ not only is optimal for achieving a final expansion ratio of approximately 11 times but also achieving the best elasticity and high compressive strength.

热塑性聚氨酯（TPU）泡沫塑料具有弹性好、抗冲击强度高、耐低温等优异性能，广泛应用于鞋类、医疗、汽车、包装、运输、航空航天等领域。然而，超临界二氧化碳（CO2）制备的TPU泡沫具有明显的收缩率，限制了其广泛应用。本研究以有利于高膨胀比的低硬度TPU为基体，通过掺入高硬度TPU调节硬度和结晶度、混合发泡剂发泡或N2再发泡两种方法制备TPU泡沫。结果表明，通过调节TPU泡沫的硬度和结晶度，可以抑制TPU泡沫的收缩行为。此外，与混合发泡剂相比，用N2再发泡可显著提高最终膨胀率。结果表明，先用CO2发泡后再用N₂发泡的TPU泡沫，不仅最终膨胀比约为11倍，而且具有最佳的弹性和较高的抗压强度。

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引用次数: 0

Performance analysis of scCO2 closed Brayton cycle applied to aero engine thermal protection considering flow and heat transfer characteristics inside the scCO2-fuel heat exchanger 考虑scCO2-燃料换热器内部流动和传热特性的scCO2闭式Brayton循环在航空发动机热防护中的应用性能分析

IF 4.4 3区工程技术 Q2 CHEMISTRY, PHYSICAL

Journal of Supercritical Fluids

Pub Date : 2025-09-17 DOI: 10.1016/j.supflu.2025.106787

Xingjian Li , Yulong Li , Jingqi Li , Shijie Xu

To clarify the cycle performance considering flow and heat transfer characteristics inside the heat exchanger, this paper constructs a calculation model which combines heat exchanger model for an onboard scCO₂ closed Brayton cycle cooling system. Based on the model, the influence of fluid mass flow rate and flow heat transfer characteristics on cycle performance are clarified. The results indicate that the scCO₂ pressure losses inside the heat exchanger is the dominate factor on the cycle performance. The heat transfer deterioration inside heat exchanger caused by laminar flow area of fuel deteriorate the cycle performance. A critical fuel mass flow rate is found that the increase in fuel mass flow rate improves cycle thermodynamics performance below it and remains roughly constant above it. Furthermore, the increase in the heat exchanger’s flow area improves cycle thermal efficiency, however decreases the power-to-weight ratio of the heat exchanger, limiting its feasibility. Ultimately, recuperated layout can enhance system thermodynamic performance but deteriorate cooling performance.

为了明确考虑换热器内部流动和换热特性的循环性能，本文结合换热器模型构建了车载scCO2闭式布雷顿循环冷却系统的计算模型。在此基础上，阐明了流体质量、流量和流动换热特性对循环性能的影响。结果表明，换热器内scCO2压力损失是影响循环性能的主要因素。燃料层流区引起的换热器内部换热恶化使循环性能恶化。在一个临界燃料质量流量下，燃料质量流量的增加可以改善循环热力学性能，而在临界燃料质量流量以上循环热力学性能基本保持不变。此外，换热器流面积的增加提高了循环热效率，但降低了换热器的功率重量比，限制了换热器的可行性。最终，回热布局可以提高系统的热力学性能，但会降低冷却性能。

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引用次数: 0

Visualization experiment and numerical analysis of supercritical CO2 flow inside porous chip: Effect of heat transfer and porous structures 多孔切屑内超临界CO2流动的可视化实验与数值分析：传热与多孔结构的影响

IF 4.4 3区工程技术 Q2 CHEMISTRY, PHYSICAL

Journal of Supercritical Fluids

Pub Date : 2025-09-17 DOI: 10.1016/j.supflu.2025.106788

Jiaxin Liu , Mengshuai Chen , Rachid Bennacer , Lin Chen

Carbon dioxide (CO₂) geological sequestration is one of the key methods to reduce atmospheric carbon emissions, yet the migration mechanisms of CO₂ within reservoirs remain unclear. This study systematically investigates the flow and heat transfer characteristics of supercritical CO₂ (sCO₂) in porous media through integrated optical visualization experiments and numerical simulations. Experimental results show that under supercritical conditions (pressure: 8.2–8.6 MPa, temperature: 32–34 °C), increasing the outlet pressure enhances momentum exchange but reduces flow uniformity, whereas raising the inlet temperature reduces fluid viscosity and smoothens density gradients, thereby improving flow homogeneity. Numerical simulations further reveal that under supercritical conditions (8.5 MPa, 305.15–318.15 K), boundary parameters including the inlet Reynolds number, inlet temperature, and wall heat flux exhibit non-monotonic influence patterns on the heat transfer coefficient (HTC), with an optimal range identified for each parameter. Exceeding this range leads to a significant reduction in HTC by 75–94 %. Under transcritical conditions (7.5–9.0 MPa, 303.15 K), the structure of the porous media effectively suppresses disturbances caused by thermophysical nonlinearities of sCO₂ through flow inertia, enabling the local heat transfer coefficient to maintain strong robustness against variations in outlet pressure and heat flux.

二氧化碳（CO2）地质封存是减少大气碳排放的关键方法之一，但CO2在水库中的迁移机制尚不清楚。通过综合光学可视化实验和数值模拟，系统研究了超临界CO₂（sCO₂）在多孔介质中的流动和换热特性。实验结果表明，在超临界工况下（压力8.2 ~ 8.6 MPa，温度32 ~ 34℃），增大出口压力可增强动量交换，但会降低流动均匀性，而提高进口温度可降低流体粘度，平滑密度梯度，从而改善流动均匀性。数值模拟进一步表明，在超临界条件下（8.5 MPa, 305.15-318.15 K），包括进口雷诺数、进口温度和壁面热流密度在内的边界参数对换热系数（HTC）表现出非单调的影响模式，并确定了每个参数的最优范围。超过这个范围会导致HTC显著减少75 - 94% %。在跨临界条件下（7.5-9.0 MPa, 303.15 K），多孔介质的结构通过流动惯性有效地抑制了sCO₂热物理非线性引起的扰动，使局部换热系数对出口压力和热流密度的变化保持较强的鲁棒性。

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引用次数: 0

Efficient fabrication of thermoplastic polyester elastomer foams with high expansion ratio and superior dimensional stability 热塑性聚酯弹性体泡沫的高效制造，具有高膨胀率和优越的尺寸稳定性

IF 4.4 3区工程技术 Q2 CHEMISTRY, PHYSICAL

Journal of Supercritical Fluids

Pub Date : 2025-09-16 DOI: 10.1016/j.supflu.2025.106784

Yujiao Zhai , Jing Zhang , Jiale Chen , Fenghao Shi , Yucai Li , Xin Wu , Chunling Xin , Yadong He

Due to its linear molecular chain structure, thermoplastic polyester elastomer (TPEE) exhibits inherently poor melt viscoelasticity and inadequate matrix strength. These limitations impair its foaming behavior and pose challenges in fabricating high-performance TPEE foams. Therefore, this work employed an epoxy chain extender (KL-E4370B) to modify TPEE. Results demonstrate that modified TPEE achieved a substantially enhanced branching degree, accompanied by a three orders of magnitude improvement in melt viscoelasticity. Notably, foaming temperature window broadened by 30 °C, while expansion ratio increased from 1.80 to 25.01. Moreover, modified TPEE exhibited a 29.96 % reduction in crystallinity, which enhanced gas permeability. This improvement effectively mitigated foam shrinkage while simultaneously accelerating recovery process. At 1.0 wt% KL-E4370B content, micro-crosslinked networks formed between molecular chains, enhancing matrix elastic modulus endowing TPEE foam with excellent self-recovery capability. Building on these results, this work successfully developed TPEE foams with simultaneous high expansion ratio and superior dimensional stability by regulating KL-E4370B content, establishing a novel strategy for engineering high-performance thermoplastic elastomer foams. Kohlrausch-Williams-Watts (KWW) model analysis further demonstrated that enhanced expansion ratio induced greater cell wall strain, which reduced the relaxation time of TPEE’s soft segments while narrowing their relaxation time distribution. This mechanistic explains the accelerated foam shrinkage behavior observed experimentally.

由于其线性分子链结构，热塑性聚酯弹性体（TPEE）固有地表现出较差的熔体粘弹性和不足的基体强度。这些限制影响了它的发泡性能，给高性能TPEE泡沫的制造带来了挑战。因此，本工作采用环氧扩链剂KL-E4370B对TPEE进行改性。结果表明，改性后的TPEE分支度显著提高，熔体粘弹性提高了3个数量级。发泡温度窗加宽30℃，膨胀比由1.80增加到25.01。改性后的TPEE结晶度降低29.96 %，提高了透气性。这种改进有效地缓解了泡沫收缩，同时加速了恢复过程。当KL-E4370B含量为1.0 wt%时，分子链之间形成微交联网络，增强了基体弹性模量，使TPEE泡沫具有优异的自恢复能力。在此基础上，通过调节KL-E4370B的含量，成功制备出具有高膨胀率和尺寸稳定性的TPEE泡沫，为工程高性能热塑性弹性体泡沫开辟了一条新途径。Kohlrausch-Williams-Watts （KWW）模型分析进一步表明，膨胀率的增加导致细胞壁应变的增大，从而减少了TPEE软段的松弛时间，缩小了其松弛时间分布。这一机制解释了实验观察到的泡沫加速收缩行为。

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引用次数: 0

Comprehensive analysis and modeling of dye diffusion within fibers in supercritical CO2 for sustainable textile dyeing 超临界CO2环境下染料在纤维内扩散的综合分析与建模

IF 4.4 3区工程技术 Q2 CHEMISTRY, PHYSICAL

Journal of Supercritical Fluids

Pub Date : 2025-09-15 DOI: 10.1016/j.supflu.2025.106786

Shihan Wang, Tong Feng, Rongzhen Wang, Lin Li, Kunpeng Yu, Haixin Sun, Jianzhong Yin

The textile industry is widely recognized as a high-pollution sector, with conventional dyeing processes marked by excessive water usage, high pollutant discharge, and low efficiency. Supercritical CO₂ dyeing has garnered attention for its environmental benefits; however, its industrial application remains limited due to inefficiencies, primarily governed by the diffusion coefficient of dyes within the fiber matrix. This study compiles and analyzes existing literature to systematically examine how temperature, pressure, dye type, and fiber type influence the diffusion coefficient. Results indicate that higher temperatures significantly enhance diffusion, consistent with the Arrhenius equation. Pressure can promote diffusion through CO₂ plasticization of fibers, but its effect is complex and condition-dependent. Low-molar-mass dyes exhibit better diffusion, and fibers with lower crystallinity—such as PMIA—are more conducive to dye penetration. A multi-variable diffusion coefficient model was developed based on the Arrhenius equation and free volume theory. All model fitting errors were within 10 %, indicating strong descriptive accuracy within the studied parameter window. However, the model is currently limited to 14 data points covering four dyes, and within a temperature range of 353 K to 413 K and a pressure range of 15 MPa to 25 MPa. This model offers a theoretical foundation for optimizing supercritical CO₂ dyeing parameters and may be extended to a broader range of fiber-dye systems in future applications.

纺织工业是公认的高污染行业，传统的染色工艺用水过多，污染物排放高，效率低。超临界CO2染色因其环境效益而备受关注；然而，由于效率低下，其工业应用仍然受到限制，主要受纤维基质内染料扩散系数的限制。本研究对已有文献进行整理和分析，系统考察温度、压力、染料类型和纤维类型对扩散系数的影响。结果表明，较高的温度显著促进了扩散，符合Arrhenius方程。压力可以促进CO2在纤维中的扩散，但其影响是复杂的，且依赖于条件。低摩尔质量的染料具有更好的扩散，而结晶度较低的纤维（如pmia）更有利于染料渗透。基于Arrhenius方程和自由体积理论建立了多变量扩散系数模型。所有模型拟合误差都在10 %以内，表明在研究参数窗口内具有很强的描述准确性。然而，该模型目前仅限于14个数据点，涵盖四种染料，温度范围为353 K至413 K，压力范围为15 MPa至25 MPa。该模型为优化超临界CO2染色参数提供了理论基础，并可在未来的应用中扩展到更广泛的纤维染料体系。

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引用次数: 0

Synergistic effects of water and methanol mixed solvents on the liquefaction of Northeastern Indian coals: Insights from product analysis 水和甲醇混合溶剂对东北印度煤液化的协同效应：来自产品分析的见解

IF 4.4 3区工程技术 Q2 CHEMISTRY, PHYSICAL

Journal of Supercritical Fluids

Pub Date : 2025-09-12 DOI: 10.1016/j.supflu.2025.106783

Govind Dubey, Prabu Vairakannu, Pankaj Tiwari

The study explored the synergistic effect of methanol as a co-solvent during the hydrothermal liquefaction of three coals from Northeastern India: Bokolia (AB), Bapung (MB), and Margherita (MG). Lignite and sub-bituminous grade coals were tested at reaction temperatures ranging from 350–400 ℃ and 30–60 min residence times, using varying ratios of methanol and water. The products included gas, oil, asphaltenes, preasphaltenes, and char. The best results were achieved with AB coal at 375 ℃ for 60 min with a water-to-methanol ratio of 1:1, yielding 41.7 wt% conversion and 13.8 wt% oil (d.a.f basis). Synergistic effects enhanced oil yield, with maximum values of 53.8 % for AB, 15.9 % for MB, and 23.6 % for MG at optimal conditions. Notably, CO in gaseous products was present in higher concentrations (5–16 vol%) across all coal types at 375 ℃, while MG oil was found to be primarily paraffinic.

研究了甲醇作为助溶剂在印度东北部三种煤的水热液化过程中的协同作用：Bokolia （AB）、Bapung （MB）和Margherita （MG）。褐煤和亚烟煤在反应温度350-400℃和30-60 min停留时间范围内，使用不同比例的甲醇和水进行测试。产品包括天然气、石油、沥青质、预沥青质和焦炭。以AB煤为原料，在375℃、60 min、水甲醇比为1:1的条件下，转化率为41.7 wt%，油收率为13.8 wt%。协同效应提高了油收率，在最佳条件下，AB、MB和MG的收率分别达到53.8% %、15.9% %和23.6% %的最大值。值得注意的是，在375℃时，所有煤类型的气态产物中CO的浓度都较高（5-16 vol%），而MG油主要是石蜡。

引用次数: 0

Molecularly engineered alkyl-anthraquinone dyes for sustainable textile dyeing in supercritical carbon dioxide 分子工程烷基蒽醌染料在超临界二氧化碳环境下的可持续染色

IF 4.4 3区工程技术 Q2 CHEMISTRY, PHYSICAL

Journal of Supercritical Fluids

Pub Date : 2025-09-12 DOI: 10.1016/j.supflu.2025.106782

Jinglong Li , Meiyu Zhen , Yutao Feng , Ziyi Lu , Chang Wang , Xiaoqing Xiong

Alkyl-chain anthraquinone dyes have promising performance but face application constraints due to hydrophobicity and pollution in conventional water-based dyeing. This study developed an eco-friendly synthesis and dyeing approach. Six dyes (AQ-5 to AQ-7, CAQ-5 to CAQ-7) were synthesized in supercritical carbon dioxide (scCO₂) via reactions of 1-chloroanthraquinone/1,5-dichloroanthraquinone with n-alkylamines. They showed good light absorption and thermal stability (5 % weight loss at 245–298°C, suitable for scCO₂ dyeing). Meanwhile, scCO₂ dyeing regularity was revealed through the synergistic regulation of multiple parameters. Optimal scCO₂ dyeing conditions for polyester were determined: 16 MPa, 130°C, 90 min for AQ-5–AQ-7; the optimal dyeing conditions for CAQ-5–CAQ-7 were determined and these were included in the range of 120–135 °C, 16 MPa, 70–100 min. Dyed fabrics had uniform fixation with excellent washing, dry, and wet rubbing over than grade 4, and good light fastness. This work establishes a green scCO₂ system, overcoming traditional limitations, and provides a theoretical basis for eco-friendly dyes/technologies.

烷基链蒽醌染料具有良好的应用前景，但在传统的水基染色中存在疏水性和污染等问题。本研究开发了一种环保的合成和染色方法。以1-氯蒽醌/1,5-二氯蒽醌与正烷基胺为原料，在超临界二氧化碳（scCO₂）中合成了6种染料（AQ-5 ~ AQ-7、CAQ-5 ~ CAQ-7）。它们具有良好的吸光性和热稳定性（在245-298°C时失重5 %，适合scCO₂染色）。同时，通过多参数的协同调控，揭示了scCO₂的染色规律。涤纶的最佳scCO₂染色条件为：AQ-5-AQ-7为16 MPa， 130℃，90 min；确定了CAQ-5-CAQ-7的最佳染色条件为120 ~ 135℃，16 MPa, 70 ~ 100 min。染色织物固色均匀，洗涤、干湿摩擦均优于4级，耐光牢度好。该研究突破了传统的局限性，建立了绿色scCO₂体系，为环保染料技术提供了理论基础。

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引用次数: 0

Shelf-life of sterilised alginate-gelatine aerogels developed through an integrated high-pressure and supercritical CO2 process 通过高压和超临界CO2综合工艺开发的灭菌海藻酸盐-明胶气凝胶的保质期

IF 4.4 3区工程技术 Q2 CHEMISTRY, PHYSICAL

Journal of Supercritical Fluids

Pub Date : 2025-09-10 DOI: 10.1016/j.supflu.2025.106781

Cristiana S.A. Bento , Dhara Leite Lopes , Cristiane Flora Villarreal , Nuno Empadinhas , Susana Alarico , Hermínio C. de Sousa , Mara E.M. Braga

Shelf-life studies on sterile biopolymeric aerogels are scarce. This study investigated four storage conditions (C₁ - C₄), varying temperature, humidity, and light exposure, on alginate-gelatine aerogels produced via an integrated high-pressure and supercritical CO₂ process. Mild storage conditions (C₁ - 25 ºC, 60 % humidity and no light) effectively preserved aerogels’ structural and functional properties, with minimal changes over time. In contrast, accelerated storage conditions (C₂ - 40 ºC, 75 % humidity, no light) induced hydrolytic degradation, causing chain scission and structural damage, due to heat and moisture. Light exposure at mild storage conditions (C₃) induced mild photooxidative effects without significant impact on properties. The combination of all stressors at accelerated storage (C₄) severely compromised network, thermal and mechanical stability. Swelling profile increased under storage but it was mitigated under conditions with high temperature and humidity. Storage for 6 months did not promote microbial growth on the sterilised aerogels under the tested conditions, confirming the effectiveness of the CO₂ sterilisation process. Aerogels did not present cytotoxicity, regardless of the storage conditions, however wound-healing potential declined under storage conditions C₂, C₃ and C₄, while C₁ maintained performance for three months.

无菌生物聚合物气凝胶的保质期研究很少。本研究研究了四种储存条件（C1 - C4），不同的温度，湿度和光照，海藻酸盐-明胶气凝胶通过高压和超临界CO2集成工艺生产。温和的储存条件（C1 - 25ºC， 60% %的湿度和无光照）有效地保存了气凝胶的结构和功能特性，随着时间的推移变化很小。相比之下，加速储存条件（C2 - 40ºC， 75% %湿度，无光照）由于热量和水分导致水解降解，导致链断裂和结构损坏。在温和储存条件下（C3）的光暴露诱导了轻微的光氧化作用，但对性能没有显著影响。在加速储存（C4）中，所有应力源的组合严重损害了网络、热稳定性和机械稳定性。贮藏过程中膨胀曲线增大，高温高湿条件下膨胀曲线减小。在测试条件下，储存6个月没有促进灭菌气凝胶上的微生物生长，证实了CO2灭菌过程的有效性。无论储存条件如何，气凝胶都没有表现出细胞毒性，但在C2、C3和C4储存条件下，伤口愈合潜力下降，而C1保存三个月。

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引用次数: 0

Tip clearance effects on the performance of a hundred kW-class supercritical CO2 turbine 叶尖间隙对百千瓦级超临界CO2涡轮性能的影响

IF 4.4 3区工程技术 Q2 CHEMISTRY, PHYSICAL

Journal of Supercritical Fluids

Pub Date : 2025-09-08 DOI: 10.1016/j.supflu.2025.106780

Kang Yang , Zhijian He , Naxin Zhang , Laijie Chen , Zheng Qin , Lintao Wang , Keyong Dong , Hailiang Li , Xinyu Li , Huimin Liu , Jian Lan , Zhongshang Song , Zhenchang Fang , Xinqi Qiao

Supercritical carbon dioxide (S-CO₂) Brayton cycle technology offers significant efficiency and environmental benefits. The turbine, a core component, critically affects system performance. In hundred-kW-class S-CO₂ turbines, the large tip clearance-to-blade height ratio significantly impacts efficiency and flow characteristics. This study combines experiments and simulations to investigate tip clearance effects.Comparison of simulation results with experimental data validates the simulation method with a maximum discrepancy of 3.3 %, confirming its reliability. The results demonstrate that under design conditions, the CFD-simulated mass flow rate is 9.67 kg/s with an isentropic efficiency of 81.5 %, while experimental results show 9.35 kg/s and 83.9 %, respectively. Further analysis of different tip clearances reveals a near-linear relationship between clearance size and turbine performance. For every 0.25 mm increase in tip clearance, the mass flow rate decreases by approximately 0.04 kg/s, and turbine efficiency declines by 1.04 %. These findings provide valuable guidance for optimizing the design of hundred-kW-class S-CO₂ turbines.

超临界二氧化碳（S-CO 2）布雷顿循环技术具有显著的效率和环境效益。汽轮机是影响系统性能的核心部件。在百千瓦级S-CO₂涡轮中，较大的叶尖间隙与叶片高度比会显著影响效率和流动特性。本研究结合实验和模拟研究了叶尖间隙的影响。仿真结果与实验数据的对比验证了仿真方法的有效性，最大误差为3.3 %，验证了仿真方法的可靠性。结果表明：在设计条件下，cfd模拟的质量流量为9.67 kg/s，等熵效率为81.5 %，而实验结果分别为9.35 kg/s和83.9 %。对不同叶尖间隙的进一步分析揭示了间隙大小与涡轮性能之间的近似线性关系。叶尖间隙每增加0.25 mm，质量流量下降约0.04 kg/s，涡轮效率下降1.04 %。这些研究结果为百千瓦级S-CO₂涡轮的优化设计提供了有价值的指导。

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引用次数: 0