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Dissociation Constant Studies of 2-Substituted 4-Formylbenzoic Acid based on Conductometric Parameters using Fuoss-Hsia Theories 基于电导参数的2-取代4-甲酰基苯甲酸解离常数研究
IF 0.8 Q3 Engineering Pub Date : 2023-02-08 DOI: 10.5541/ijot.1136209
Kosrat N. Kaka, R. Omer, Salam G. Taher, W. M. H. Hamad
The dissociation constant is a quantitative measure of the strength of an acid in solution. This study examines dissociation constant for the series substituted acids like Ortho-alkoxy-4-formylbenzoic acid. The use of (2-methoxy ethanol) as a solvent contributed to the study expected to form free ions or solvent separated ion pair which has been studied with the use conductometric method at different temperatures ranged from 293.15 to 318.15K. The study aims at figuring out dissociation constant, equivalent conductance at infinity dilution, and Walden product by minimization technique using Fuoss-Hsia for both (Modified and Complete) equations. It has been found in the results that the calculated values based on statistical sum square (different between practical and theoretical values) is equivalent conductance at infinity dilution and dissociation constant. It has also been observed that increase the temperature leads to the increase of the molar conductance at infinity dilution, and the increase in association. Moreover, the substituted alkoxy group also affected dissociation of compounds. In this study, the thermodynamic parameters (Ho, Go and So) have also been evaluated and discussed. Finally, the effect of substituent groups on rate of dissociation was studied and explained with agreement to the principles of mesomeric(M) and Inductive effect(I) of substituent groups on dissociation constant.
解离常数是溶液中酸的强度的定量量度。本研究考察了邻烷氧基-4-甲酰苯甲酸等系列取代酸的解离常数。使用(2-甲氧基乙醇)作为溶剂有助于研究期望在293.15 ~ 318.15K不同温度下形成自由离子或溶剂分离离子对,并使用电导法进行了研究。研究的目的是利用fuss - hsia最小化技术计算解离常数、无限稀释时的等效电导和瓦尔登积(修正和完全)方程。结果发现,基于统计平方和的计算值(实际值与理论值不同)是无限稀释时的等效电导和解离常数。还观察到,温度的升高导致无限稀释时摩尔电导的增加和结合力的增加。此外,取代的烷氧基也影响化合物的解离。在本研究中,热力学参数(Ho,Go和So)也进行了评估和讨论。最后,根据取代基对解离常数的中介效应(M)和诱导效应(I)原理,研究并解释了取代基对解离速率的影响。
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引用次数: 0
Time-Fractional Cattaneo-Type Thermoelastic Interior-Boundary Value Problem Within A Rigid Ball 刚性球内时间分数Cattaneo型热弹性内边值问题
IF 0.8 Q3 Engineering Pub Date : 2023-01-06 DOI: 10.5541/ijot.1170335
G. Dhameja, L. Khalsa, V Varghese
The paper discusses the solution of an interior-boundary value problem of one-dimensional time-fractional Cattaneo-type heat conduction and its stress fields for a rigid ball. The interior value problem describes the dependence of the boundary conditions within the ball's inner plane at any instant with a prescribed temperature state, in contrast to the exterior value problem, which relates the known surface temperature to boundary conditions. A single-phase-lag equation with Caputo fractional derivatives is proposed to model the heat equation in a medium subjected to time-dependent physical boundary conditions. The application of the finite spherical Hankel and Laplace transform technique to heat conduction is discussed. The influence of the fractional-order parameter and the relaxation time is examined on the temperature fields and their related stresses. The findings show that the slower the thermal wave, the bigger the fractional-order setting, and the higher the period of relaxation, the slower the heat flux propagates.
讨论了刚性球一维时分式cattaneo型热传导内边值问题的解及其应力场。内值问题描述了球内平面内边界条件在任何时刻与规定温度状态的依赖关系,而外值问题则将已知表面温度与边界条件联系起来。提出了一个带卡普托分数阶导数的单相滞后方程来模拟受时变物理边界条件影响的介质中的热方程。讨论了有限球面汉克尔和拉普拉斯变换技术在热传导中的应用。考察了分数阶参数和弛豫时间对温度场及其相关应力的影响。结果表明:热波越慢,分数阶设置越大,松弛周期越长,热流传播越慢;
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引用次数: 0
The Bosons of the Conventional Superconductors 常规超导体的玻色子
IF 0.8 Q3 Engineering Pub Date : 2023-01-03 DOI: 10.5541/ijot.1169691
U. Köbler
For the conventional superconductors it will be shown that not only the superconducting energy gap, Egap(T=0), and the critical field, Bc(T=0), but also the London penetration depth, λL(T=0), scale in a reasonable approximation with the superconducting transition temperature, TSC, as ~TSC, ~TSC2 and ~T-1/2, respectively. From these scaling relations the conclusion obtained earlier, using a completely different method, is confirmed that the London penetration depth corresponds to the diameter of the Cooper-pairs. As a consequence, only one layer of Cooper pairs is sufficient to shield an external magnetic field completely. The large diamagnetism of the superconductors is caused by the large orbital area of the Cooper-pairs. From the fact that, in the zero-field ground state, the temperature dependence of the superconducting heat capacity is given above and below TSC by power functions of absolute temperature it follows that the only critical point is T=0. The superconducting transitions of the element superconductors, therefore, are all within the critical range at T=0. As a consequence, above and below TSC there is short-range order only. As we know from Renormalization Group (RG) theory, in the critical range the dynamics is the dynamics of a boson field, exclusively. Evidently, the Cooper-pairs have to be considered as the short-range ordered units created by this boson field. It is reasonable to assume that the relevant bosons in the superconducting state are identical with the bosons giving rise to the universal linear-in-T electronic heat capacity above TSC. Plausibility arguments will be given that these bosons must be electric quadrupole radiation generated by the non-spherical charge distributions in the soft zones between the metal atoms. The radiation field emitted by an electric quadrupole can be assumed to be essentially curled or circular. In the ordered state below TSC, the bosons are condensed in resonating spherical modes which encapsulate the two Cooper-pair electrons and shield their charge perfectly.
对于常规超导体,不仅超导能隙Egap(T=0)和临界场Bc(T=0),而且伦敦穿透深度λL(T=0)与超导转变温度TSC,分别为~TSC, ~TSC2和~T-1/2的合理近似。从这些标度关系出发,用一种完全不同的方法证实了先前得到的结论,即伦敦穿透深度对应于库珀对的直径。因此,仅一层库珀对就足以完全屏蔽外部磁场。超导体的大抗磁性是由库珀对的大轨道面积引起的。在零场基态下,超导热容的温度依赖性由绝对温度的幂函数给出TSC以上和TSC以下,由此可知,唯一的临界点是T=0。因此,元素超导体的超导跃迁在T=0时都在临界范围内。因此,在TSC以上和以下只有短期订单。从重整化群(RG)理论可知,在临界范围内,动力学仅是玻色子场的动力学。显然,库珀对必须被认为是由这个玻色子场产生的短程有序单位。可以合理地假设超导态的相关玻色子与产生TSC以上普遍线性电子热容的玻色子是相同的。给出了这些玻色子一定是由金属原子间软区非球形电荷分布产生的电四极辐射的合理性论证。由电四极杆发射的辐射场可以假定基本上是卷曲或圆形的。在低于TSC的有序态下,玻色子被凝聚成共振的球形模式,这种模式可以很好地封装两个库珀对电子并屏蔽它们的电荷。
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引用次数: 1
Thermodynamic Studies on Sr5Nb4O15 Sr5Nb4O15的热力学研究
IF 0.8 Q3 Engineering Pub Date : 2022-12-24 DOI: 10.5541/ijot.1157497
P. Samui, Santosh Bhojane, B. Singh, Swarup Rakshi̇t
The SrO–Nb2O5 system, especially Sr5Nb4O15 compound is of interest for their use as an electroceramics. In this work, Sr5Nb4O15 compound was synthesized by solid-state reaction and characterised by XRD. Thermodynamic properties like heat capacity, enthalpy of formation and Gibbs energy of formation of Sr5Nb4O15 have been measured. The standard molar enthalpy of formation of Sr5Nb4O15(s) was determined using an oxide melt solution high temperature calorimeter. Based on these experimental data, a self-consistent thermodynamic function of this compound was also generated. This thermodynamic data is essential for the optimization of synthesis conditions for materials and for the evaluation of their stability under appropriate technological operating conditions.
SrO–Nb2O5体系,特别是Sr5Nb4O15化合物,因其用作电陶瓷而备受关注。本工作通过固相反应合成了Sr5Nb4O15化合物,并用XRD对其进行了表征。测定了Sr5Nb4O15的热容、生成焓和生成吉布斯能等热力学性质。使用氧化物熔融溶液高温量热计测定Sr5Nb4O15(s)的标准摩尔生成焓。基于这些实验数据,还产生了该化合物的自洽热力学函数。该热力学数据对于优化材料的合成条件以及评估其在适当的技术操作条件下的稳定性至关重要。
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引用次数: 0
Solubility Prediction of Lornoxicam in Different Pure Solvents Using Semi-Empirical Correlations and Thermodynamic Models 用半经验关联和热力学模型预测氯诺昔康在不同纯溶剂中的溶解度
IF 0.8 Q3 Engineering Pub Date : 2022-12-14 DOI: 10.5541/ijot.1138056
Rahul Kumar, A. Thakur, A. Kulabhi, A. Mishra
The solubility data of Active Pharmaceutical Ingredients in organic solvents is an essential for pharmaceutical crystallization and drug formulation. In this work, two semi-empirical correlations- the Yaws model and λ-h model- and two thermodynamic models – Wilson Model and the Non-random two-liquid model- are used to estimate the solubility of lornoxicam in ethanol and water. The model parameters and correlations coefficients are calculated by optimizing the average relative deviation. The values of these parameters will be helpful to estimate the solubility of lornoxicam at different temperatures where the experimental solubility data is not available. The predicted solubility data of lornoxicam can be further utilized in the pharmaceutical crystallization and drug formulation.
活性药物成分在有机溶剂中的溶解度数据是药物结晶和药物配方研究的重要数据。在这项工作中,使用两个半经验相关性-雅司模型和λ-h模型-和两个热力学模型-威尔逊模型和非随机双液体模型-来估计氯诺昔康在乙醇和水中的溶解度。通过优化平均相对偏差计算模型参数和相关系数。这些参数的值将有助于估计氯诺昔康在不同温度下的溶解度,在没有实验溶解度数据的情况下。氯诺昔康的溶解度预测数据可进一步用于药物结晶和药物配制。
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引用次数: 0
Thermodynamic Properties of Ethanol + Pyridine, Ethanol + Benzene, and Pyridine + Benzene Mixtures at Temperature 298.15 K and Under Atmospheric Pressure 298.15 K和常压下乙醇+吡啶、乙醇+苯和吡啶+苯混合物的热力学性质
IF 0.8 Q3 Engineering Pub Date : 2022-12-14 DOI: 10.5541/ijot.1173589
Arber Zeqiraj, A. Gjevori, Artan Llozana, N. Syla, F. Aliaj
Experimental densities, viscosities, refractive indices, and sound speeds at temperature 298.15 K and atmospheric pressure are reported for the binary liquid mixtures of ethanol + benzene, ethanol + pyridine, and benzene + pyridine. From these experimental data, various thermodynamic excess and deviation properties were calculated and fitted by the Redlich-Kister polynomial to determine the adjustable coefficients and the standard deviations. The number of Redlich-Kister coefficients for significantly representing each thermodynamic property was optimized by applying the F-test. The variation of thermodynamic excess and deviation properties with composition has been interpreted in terms of molecular interactions between components of the mixture and structural effects. Furthermore, several theoretical and semi-empirical models were used to predict the refractive indices and sound speeds of the investigated mixtures. The predicting ability of each model was ascertained in terms of mean absolute percentage deviation between experimental and calculated data.
报道了乙醇+苯、乙醇+吡啶和苯+吡啶的二元液体混合物在298.15K温度和大气压下的实验密度、粘度、折射率和声速。根据这些实验数据,计算了各种热力学过剩和偏差特性,并通过Redlich-Kister多项式进行拟合,以确定可调系数和标准偏差。通过应用F检验优化了显著代表每种热力学性质的Redlich-Kister系数的数量。热力学过剩和偏离性质随组成的变化已从混合物组分之间的分子相互作用和结构效应的角度进行了解释。此外,还使用了几个理论和半经验模型来预测所研究混合物的折射率和声速。每个模型的预测能力是根据实验数据和计算数据之间的平均绝对百分比偏差来确定的。
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引用次数: 2
Emissivity Prediction for an IR Camera During Laser Welding of Aluminum 铝激光焊接红外相机发射率预测
IF 0.8 Q3 Engineering Pub Date : 2022-12-01 DOI: 10.5541/ijot.1129559
A. Metallo
Laser processing is becoming increasingly important in industrial applications. The success of the process relies on two fundamental parameters: the surface temperature of the medium and the thickness of the hardened layer. One of the most important factors during a laser process is certainly the temperature, which presents high temperature gradients. The speed at which a material undergoes a phase transition, the chemical reactions that take place during processing and the properties of the material are all dependent on temperature changes. Consequently, the measure of temperature is a demanding undertaking. This study proposes to measure temperature for the duration of laser welding with the infrared camera (IR) Optris PI. To restore the real temperature based on the brightness temperature values measured by the IR camera is needed to evaluate the emissivity to be attributed to the IR camera. For this purpose, firstly, the isotherms consistent with the melting point of aluminum (785 K) were assessed and then compared with the temperature distribution gauged in the zone of irradiation of the laser. Such data were then compared with the thickness of the melted zone. The use of the melting point isotherm allowed the calculation of the value of emissivity and the restoration of the temperature. Thermography software data acquisition wrongly presupposes the emissivity value does not change. This generates incorrect thermographic data. The surface emissivity normally hinges on temperature. Therefore, the values on which the literature relies may not work for materials of interest in the conditions of the process. This is particularly the case, where welding is carried out in keyhole mode (Tmax = Tvap). However, the physical phenomena involved, including evaporation and plasma plume formation, high spatial and temporal temperature gradients, and non-equilibrium phase transformations, influence the optical conditions of the brightness of the emission of light from the molten pool, making, De Facto, the emissivity value not constant. Thus, what we propose here is a methodological procedure that allows the measurement of the effective emissivity of the surface, at the same time taking into consideration the consequence of physical phenomena and the conditions of the surface. Two procedures (Standard and Simplified) capable of providing the correct emissivity value in relation to the working parameters have been proposed. The results showed that the procedures are correct, fast, and easy to use.
激光加工在工业应用中越来越重要。该工艺的成功取决于两个基本参数:介质的表面温度和硬化层的厚度。激光加工过程中最重要的因素之一当然是温度,它呈现出高的温度梯度。材料发生相变的速度、加工过程中发生的化学反应以及材料的性质都取决于温度变化。因此,测量温度是一项艰巨的任务。本研究提出用红外相机Optris PI测量激光焊接过程中的温度。为了基于红外相机测量的亮度温度值恢复真实温度,需要评估归属于红外相机的发射率。为此,首先评估与铝熔点(785K)一致的等温线,然后将其与在激光照射区域中测量的温度分布进行比较。然后将这些数据与熔化区的厚度进行比较。熔点等温线的使用允许计算发射率值和恢复温度。热成像软件数据采集错误地假定发射率值不变。这会产生不正确的热成像数据。表面发射率通常取决于温度。因此,文献所依赖的价值观可能不适用于在过程条件下感兴趣的材料。这尤其是在锁孔模式(Tmax=Tvap)下进行焊接的情况。然而,所涉及的物理现象,包括蒸发和等离子体羽流的形成、高的空间和时间温度梯度以及非平衡相变,会影响熔池发光亮度的光学条件,从而使发射率值不恒定。因此,我们在这里提出的是一种方法学程序,该程序允许测量表面的有效发射率,同时考虑物理现象和表面条件的后果。提出了两种能够提供与工作参数相关的正确发射率值的程序(标准程序和简化程序)。结果表明,该程序正确、快速、易用。
{"title":"Emissivity Prediction for an IR Camera During Laser Welding of Aluminum","authors":"A. Metallo","doi":"10.5541/ijot.1129559","DOIUrl":"https://doi.org/10.5541/ijot.1129559","url":null,"abstract":"Laser processing is becoming increasingly important in industrial applications. The success of the process relies on two fundamental parameters: the surface temperature of the medium and the thickness of the hardened layer. One of the most important factors during a laser process is certainly the temperature, which presents high temperature gradients. The speed at which a material undergoes a phase transition, the chemical reactions that take place during processing and the properties of the material are all dependent on temperature changes. Consequently, the measure of temperature is a demanding undertaking. This study proposes to measure temperature for the duration of laser welding with the infrared camera (IR) Optris PI. To restore the real temperature based on the brightness temperature values measured by the IR camera is needed to evaluate the emissivity to be attributed to the IR camera. For this purpose, firstly, the isotherms consistent with the melting point of aluminum (785 K) were assessed and then compared with the temperature distribution gauged in the zone of irradiation of the laser. Such data were then compared with the thickness of the melted zone. The use of the melting point isotherm allowed the calculation of the value of emissivity and the restoration of the temperature. Thermography software data acquisition wrongly presupposes the emissivity value does not change. This generates incorrect thermographic data. The surface emissivity normally hinges on temperature. Therefore, the values on which the literature relies may not work for materials of interest in the conditions of the process. This is particularly the case, where welding is carried out in keyhole mode (Tmax = Tvap). However, the physical phenomena involved, including evaporation and plasma plume formation, high spatial and temporal temperature gradients, and non-equilibrium phase transformations, influence the optical conditions of the brightness of the emission of light from the molten pool, making, De Facto, the emissivity value not constant. Thus, what we propose here is a methodological procedure that allows the measurement of the effective emissivity of the surface, at the same time taking into consideration the consequence of physical phenomena and the conditions of the surface. Two procedures (Standard and Simplified) capable of providing the correct emissivity value in relation to the working parameters have been proposed. The results showed that the procedures are correct, fast, and easy to use.","PeriodicalId":14438,"journal":{"name":"International Journal of Thermodynamics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46874662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Thermodynamic Modeling of Liquid-Liquid Equilibrium in Ternary Systems with Biodiesel and Isolated Ester (Methyl Palmitate) 生物柴油与分离酯(棕榈酸甲酯)三元体系液液平衡的热力学模型
IF 0.8 Q3 Engineering Pub Date : 2022-12-01 DOI: 10.5541/ijot.1136615
Jéssyca K. A. Bezerra, Maria Rosiane de Almeida Andrade, Edyjancleide Rodrigues Si̇lva, L. J. N. Duarte, Gilson Gomes Medei̇ros, E. L. B. Barros Neto
Liquid-liquid equilibrium data were measured and analyzed for two ternary systems (biodiesel + methanol + glycerol and methyl palmitate + methanol + glycerol). Biodiesel, produced by the conventional chemical route at 60 °C for 60 min, using methanol and soybean oil at a molar rate of 10:1 and potassium hydroxide concentration (KOH) of 1 wt% exhibited thermal decomposition at temperatures between 100 and 250 ºC, reaching mass loss of approximately 98.8%, confirming soybean oil conversion into biodiesel by gas chromatography and thermogravimetry. Tie line composition quality was verified using Othmer-Tobias and Hand correlation equations. The distribution and selectivity coefficients were calculated for the immiscibility regions. The experimental tie line data exhibited good correlation in the UNIQUAC and NRTL thermodynamic models. The biodiesel system displayed deviations of 0.66 and 0.53% for the UNIQUAC and NRTL models, respectively. In addition, the methyl palmitate system showed a 1.23 and 0.48% deviation for the UNIQUAC and NRTL model, respectively. The individual behavior of the main biodiesel esters , based on the UNIQUAC model parameters, demonstrated that the type of fatty acid does not interfere in model correlation, likely due to the similarity between their composition and properties.
测量并分析了两种三元体系(生物柴油+甲醇+甘油和棕榈酸甲酯+甲醇+甘油)的液液平衡数据。以甲醇和大豆油为原料,摩尔比为10:1,氢氧化钾浓度为1wt %,在60℃、60 min条件下生产生物柴油,在100 ~ 250℃的温度下发生热分解,质量损失约为98.8%,通过气相色谱和热重法证实了大豆油转化为生物柴油。利用other - tobias和Hand相关方程验证了线材成分质量。计算了非混相区的分布系数和选择性系数。在UNIQUAC和NRTL热力学模型中,实验线数据具有良好的相关性。对UNIQUAC和NRTL模型,生物柴油系统的偏差分别为0.66和0.53%。此外,棕榈酸甲酯体系对UNIQUAC和NRTL模型的偏差分别为1.23%和0.48%。基于UNIQUAC模型参数的主要生物柴油酯的个体行为表明,脂肪酸的类型不会干扰模型相关性,这可能是由于它们的组成和性质之间的相似性。
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引用次数: 1
Thermodynamic Assessment of the Impact of Pregnancy and Lactation on the Longevity of Women 怀孕和哺乳对女性寿命影响的热力学评估
IF 0.8 Q3 Engineering Pub Date : 2022-12-01 DOI: 10.5541/ijot.1145655
Gizem Ulu, Melek Ece Öngel, B. Yılmaz, M. Özilgen
Effects of the pregnancy and the following lactation periods on the lifespan entropy of the women has been evaluated. In the case of singleton pregnancy, a wealthy woman may generate 1.5% and in the case of twin pregnancy 2.1% of the total lifespan entropy of a non-pregnant wealthy women. In the case of a poor woman the singleton pregnancy, may generate 1.8% and in case of the twin pregnancy 2.1% of the total lifespan entropy generated by the non-pregnant wealthy woman. Results of the diet-based thermodynamic calculations for the poor women are compared with the demographic data collected across pre-industrial Europe and a good agreement was found.
已经评估了妊娠期和随后的哺乳期对妇女寿命熵的影响。在单胎妊娠的情况下,富裕女性可能产生非妊娠富裕女性总寿命熵的1.5%,在双胎妊娠的情形下,可能产生2.1%。在贫困妇女的情况下,单胎妊娠可能产生1.8%的总寿命熵,在双胎妊娠的情况下可能产生2.1%的总寿命熵值,由未怀孕的富裕妇女产生。将贫困妇女基于饮食的热力学计算结果与工业化前欧洲收集的人口统计数据进行了比较,结果一致。
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引用次数: 1
Thermodynamic and Thermophysical Properties of Air as a Mixture by Using Schreiber-Pitzer EoS 用Schreiber-Pitzer方程研究空气作为混合物的热力学和热物理性质
IF 0.8 Q3 Engineering Pub Date : 2022-11-24 DOI: 10.5541/ijot.1169686
Özay Akdemi̇r, M. T. Coban
Air is one of the most important substances used in industrial and technological applications. Applications of air require a consistent set of reliable data on its thermodynamic and thermophysical properties. Over the last few decades, researchers have developed a number of empirical and theoretical models for the correlation and prediction of the thermodynamic and thermophysical properties of pure fluids and mixtures. The ideal gas Equation of State (EoS) is used in gas thermodynamic property calculations extensively, but in applications with higher pressure zones, the error levels are increasing. For most applications, an equation of state with better accuracy of thermodynamic properties will be required for extreme cases. In this study, Schreiber-Pitzer EoS is considered for better accuracy of the thermodynamic properties for air mixture. A set of computer programs were developed in java language to calculate the thermodynamic and thermophysical properties of air as a mixture of Nitrogen, Oxygen and Argon. The Schreiber-Pitzer EoS results are compared with Peng-Robinson EoS, Redlich-Kwong EoS, Van der Waals EoS, and ideal gas EoS utilizing cubic spline curve fitting for cp values. The thermodynamic and thermophysical property results and percentages of differences are calculated. The percentages of differences are increasing with increasing pressure and decreasing temperature.
空气是工业和技术应用中最重要的物质之一。空气的应用需要一套关于其热力学和热物理性质的一致的可靠数据。在过去的几十年里,研究人员已经开发了许多经验和理论模型,用于预测纯流体和混合物的热力学和热物理性质。理想气体状态方程(EoS)广泛应用于气体热力学性质的计算,但在高压区域的应用中,误差水平越来越大。对于大多数应用,在极端情况下需要具有更好的热力学性质精度的状态方程。在本研究中,考虑了Schreiber-Pitzer方程,以提高空气混合物热力学性质的准确性。用java语言编写了一套计算氮气、氧气和氩气混合空气的热力学和热物理性质的计算机程序。利用三次样条曲线拟合cp值,将Schreiber-Pitzer方程结果与Peng-Robinson方程、Redlich-Kwong方程、Van der Waals方程和理想气体方程进行了比较。计算了热力学和热物理性质的结果以及差异的百分比。差异的百分比随压力的增加和温度的降低而增加。
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引用次数: 0
期刊
International Journal of Thermodynamics
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