Influence Of Temperature Research Articles

Experimental studies of a remote device for biometric identification of the pre-mastitis state of the udder of dairy cows

Analysis of development of dairy cattle breeding in the Republic of Belarus is presented. The problems of reducing milk productivity and the period of economic use of dairy cows as a result of mastitis disease are noted. The importance of timely detection of sick animals, as well as treatment of the inflammatory process of the udder in the early stages is noted. The results of theoretical and experimental studies of a mock-up sample of a biometric identification device for the pre-mastitis state of udder of dairy cows are presented. In the course of experimental studies, a significant influence of ambient temperature on the thermal imaging picture was revealed, based on which the values of the radiation coefficient for cows were determined. The final adjustment of the previously established temperature ranges was made when determining one or another form of mastitis, namely, within 32.0−36.3 ℃ – the range of normal temperatures, 36.4−37.7 ℃ – “Subclinical mastitis”, 37.8−39.0 ℃ – “Clinical mastitis”. The most significant factors and optimization parameter have been determined. The percentage of the useful area of the studied object is selected as the optimization parameter. Based on the processing of experimental data, a mathematical model is obtained, described by a regression equation in the form of a polynomial of the second degree. The rational parameters of the device for biometric identification of the pre-mastitis state of the udder of dairy cows were obtained, namely: the angle of inclination of the thermal imaging module αо – 2,7o, the focal length to the object l – 794 mm, installation height of the thermal imaging module h – 495 mm. Also, based on the conducted research, priority areas and opportunities for development of the domestic agro-industrial complex through creation of integrated systems for monitoring the physiological state of animals within the framework of development of digital automated technologies of a “smart” farm have been identified.

Joint influence of the North Atlantic sea surface temperature and the Barents sea-ice concentration on the dipole pattern of Eurasian surface air temperature in March

In recent decades, an increase in the frequency of extreme events in early spring across Eurasia has resulted in significant impacts on crop yields and socio-economic development. However, the variations of March surface air temperature (SAT) over Eurasia and mechanisms are still unclear. This study aims to investigate the dominant mode of the March surface air temperature (SAT) over Eurasia during 1979–2022, and its relationship with sea surface temperature (SST) and sea ice concentration (SIC). The results reveal the prevalence of a dipole mode of the Eurasian SAT anomalies (SATAs) in March characterized by positive SATAs in northern (50°N–80°N) Eurasia and negative ones in southern (10°N–45°N) region. Further analyses demonstrate that this dipole mode of Eurasian SATAs shows significant relationships with a positive phase of the North Atlantic tripole SST anomalies (NAT SSTAs), as well as with the decline of Barents Sea SIC anomalies (SICAs). Associated with the NAT SSTAs and the Barents Sea SICAs during March, two Rossby wave trains propagate towards Eurasia through different ways, one is propagating eastwards from the mid-latitude of the North Atlantic to Eurasia, and another one spreads from the polar region to Eurasia. Modulated by these two wave trains, anomalous near-surface southwesterly (northeasterly) wind induces more (less) warm air towards northern Eurasia, while more (less) cloud emerges in southern Eurasia and causes less (more) solar radiation reaching southern Eurasia, leading to the dipole mode of the Eurasian SATAs in March. These results are further confirmed by numerical experiments from the version 5 of the Community Atmosphere Model forced by the above mentioned SSTAs and SICAs.

Comparison of heavy metal contaminants removal using EDTA and Cyanex 302 as chelating agents for supercritical CO2-based soil remediation

Supercritical CO2-based soil remediation technology has become one new method with its advantages of high efficiency, environmental protection, and no secondary pollution. In this study, experiments on a kilogram-scale experimental system have been conducted under different pressures, temperatures, processing times, etc. A wide range of parameter conditions (∼75 °C, ∼40 MPa, ∼40 min) have been tested to explore parameter effects on the removal efficiencies (RE) of metal contaminants: lead, chromium, and arsenic. Comparisons between Cyanex 302 and Ethylene Diamine Tetraacetic Acid (EDTA) as chelators have been conducted: (1) Both Cyanex 302 and EDTA show significant role in promoting the soil remediation process under supercritical CO2 remediation process. Additionally, the removal efficiency of EDTA for the three metals is generally lower than that of Cyanex 302 under the same operating conditions. (2) Cyanex 302 exhibits selectivity for metals. For Cyanex 302, the RE of both lead (Pb) and arsenic (As) was quite high (>93 %), while the removal efficiency of chromium (Cr) showed an obvious regularity with the increase of temperature, pressure and processing time, from 37 % to 83 %. (3) For EDTA cases, the RE of lead (Pb), chromium (Cr) and arsenic (As) showed different trends: the lowest removal efficiency found to be 48 %, 15 %, 28 % at 20 MPa, 35 °C, 20 min conditions, respectively; and the highest of 83 %, 63 %, 64 %, respectively, at 30 MPa, 55 °C conditions. EDTA cases showed different results for all three metals: the influence of temperature on removal efficiency is most obvious, while the influence of processing time on efficiency is neglectable.

Liquid Chromatographic Enantioseparation of Newly Synthesized Fluorinated Tryptophan Analogs Applying Macrocyclic Glycopeptides-Based Chiral Stationary Phases Utilizing Core-Shell Particles.

Due to the favorable features obtained through the incorporation of fluorine atom(s), fluorinated drugs are a group with emerging pharmaceutical importance. As their commercial availability is still very limited, to expand the range of possible candidates, new fluorinated tryptophan analogs were synthesized. Control of enantiopurity during the synthesis procedure requires that highly efficient enantioseparation methods be available. In this work, the enantioseparation of seven fluorinated tryptophans and tryptophan was studied and compared systematically to (i) develop analytical methods for enantioselective separations and (ii) explore the chromatographic features of the fluorotrytophans. For enantioresolution, macrocyclic glycopeptide-based selectors linked to core-shell particles were utilized, applying liquid chromatography-based methods. Application of the polar-ionic mode resulted in asymmetric and broadened peaks, while reversed-phase conditions, together with mobile-phase additives, resulted in baseline separation for all studied fluorinated tryptophans. The marked differences observed between the methanol and acetonitrile-containing eluent systems can be explained by the different solvation abilities of the bulk solvents of the applied mobile phases. Among the studied chiral selectors, teicoplanin and teicoplanin aglycone were found to work effectively. Under optimized conditions, baseline separations were achieved within 6 min. Ionic interactions were semi-quantitatively characterized and found to not influence enantiorecognition. Interestingly, fluorination of the analytes does not lead to marked changes in the chromatographic characteristics of the methanol-containing eluents, while larger differences were noticed when the polar but aprotic acetonitrile was applied. Experiments conducted on the influence of the separation temperature indicated that the separations are enthalpically driven, with only one exception. Enantiomeric elution order was found to be constant on both teicoplanin and teicoplanin aglycone-based chiral stationary phases (L < D) under all applied chromatographic conditions.

Condensation heat transfer performance of R290 in a plate heat exchanger for electric vehicle heat pumps

In the continuous improvement of electric vehicles driving range, a heat pump system with low-global warming potential (GWP) refrigerant is a promising solution. In the present work, the condensation heat transfer coefficient (HTC) and frictional pressure drop (FPD) were experimentally evaluated in an offset strip fins embedded plate heat exchanger (PHE), using an eco-friendly, low-GWP refrigerant R290 as the working fluid. A Modified Wilson Plot Method was used to predict the heat transfer of the coolant side (water/ethylene glycol; 50/50 %). The main focus of the present study revolves around the R290-to-coolant condensation experiment, wherein we analyzed the influence of mass flux (G = 20–50 kg m−2 s−1), heat flux (q = 3–12 kW m−2), and saturation temperature (Tsat = 40–55 °C) on HTC and FPD within the PHE while variable mean vapor quality (xm). According to the results, all experimental conditions were fall in the forced-convection condensation regime. The results state that HTC increases with a rise in q, G, and xm, but decreases with a surge in Tsat. Conversely, FPD increases with a rise in G and xm, and decreases with a escalation in Tsat, while q has no significant impact. Correlations were developed to predict the Nusselt number and friction factor values of R290 with mean absolute errors of 10.6 % and 11.2 %, respectively. These correlations are compared to previous research findings, signifying their efficacy in predicting the heat transfer characteristics of R290 within PHEs.

Effect of Initial Microstructure on the Temperature Dependence of the Flow Stress and Deformation Microstructure under Uniaxial Compression of Ti-407

In this study, the influence of initial microstructure and deformation temperature on the flow stress behavior and microstructural evolution of TIMETAL®407 (Ti-407) alloy are investigated. For this purpose, compression cylinders were β-annealed at 940 °C and then cooled to room temperature using furnace cooling, static air, and water quenching to promote three initial microstructures with different α lath thicknesses. The annealed cylinders were compressed isothermally in the range of 750 °C to 910 °C at a constant crosshead speed of 0.05 mm/s up to an engineering strain of −0.8. The resulting stress–strain curves are discussed in terms of the morphology and distribution of the α and β phases. It was found that flow stress is inversely proportional to deformation temperature for all initial microstructures. At the lowest temperatures, compressive yield strength was higher in water-quenched and air-cooled samples than in furnace-cooled specimens, suggesting that the acicular α-phase morphology obtained by rapid cooling could enhance mechanical strength by hindering dislocation motion. Two high-temperature flow regimes were determined based on the shape of the flow stress curves, indicating microstructural changes occurring during deformation. At higher temperatures, the effect of the initial microstructure is negligible as the primary α phase is transformed to the β phase at around 850 °C irrespective of the initial α-lath thickness.

Influence of initial temperature of water analyte on the readings of optical sensors based on surface plasmon resonance

The analysis of additional aspects of thermal influence on the sensory effect of the three-layer optical structure “prism - gold nanolayer - water” was continued. Here, the influence of the initial temperature of the “gold nanolayer - water” system on the surface plasmon resonance wavelength change is studies. It was established that the change in the value of the sensor effect along the wavelength of the surface plasmon resonance in the range of initial temperatures from 20 °C to 25 °C is insignificant. With an increase in the initial temperature to ∼100 °C, the change in the surface plasmon resonance wavelength can reach 0.75%, and is fixed experimentally.

Increased global cropland greening as a response to the unusual reduction in atmospheric PM₂.₅ concentrations during the COVID-19 lockdown period

The devastating effects of COVID-19 pandemic have widely affected human lives and economy across the globe. There were significant changes in the global environmental conditions in response to the lockdown (LD) restrictions made due to COVID-19. The direct impact of LD on environment is analysed widely across the latitudes, but its secondary effect remains largely unexplored. Therefore, we examine the changes in particulate matter (PM₂.₅) during LD, and its impact on the global croplands. Our analysis finds that there is a substantial decline in the global PM₂.₅ concentrations during LD (2020) compared to pre-lockdown (PreLD: 2017–2019) in India (10–20%), East China (EC, 10%), Western Europe (WE, 10%) and Nigeria (10%), which are also the cropland dominated regions. Partial correlation analysis reveals that the decline in PM₂.₅ positively affects the cropland greening when the influence of temperature, precipitation and soil moisture are limited. Croplands in India, EC, Nigeria and WE became more greener as a result of the improvement in air quality by the reduction in particulates such as PM₂.₅ during LD, with an increase in the Enhanced Vegetation Index (EVI) of about 0.05–0.1, 0.05, 0.05 and 0.05–0.1, respectively. As a result of cropland greening, increase in the total above ground biomass production (TAGP) and crop yield (TWSO) is also found in EC, India and Europe. In addition, the improvement in PM₂.₅ pollution and associated changes in meteorology also influenced the cropland phenology, where the crop development stage has prolonged in India for wet-rice (1–20%) and maize (1–10%). Therefore, this study sheds light on the response of global croplands to LD-induced improvements in PM₂.₅ pollution. These finding have implications for addressing issues of air pollution, global warming, climate change, environmental conservation and food security to achieve the Sustainable Development Goals (SDGs).

Influence of temperature on the process of preparing homogenised magnesium-zinc alloy spherical powders using the relative vacuum method

The production of magnesium-zinc (Mg-Zn) alloy spherical powders is complex and expensive. As they have extensive applications in a wide variety of fields including military manufacturing, aerospace, and biomedicine, there is an urgent need to explore new production processes for Mg-Zn alloy spherical powders. In this study, 5 wt% homogenised Mg-Zn alloy spherical powder was prepared using the relative vacuum method. The effects of the insulation time, maximum temperature, and heating rate on the morphology, size distribution, and particle size of the Mg-Zn alloy spherical powder were investigated. The results indicated that the insulation time had the greatest influence on the particle size of the spherical powder, whereas the maximum temperature and heating rate had significant impacts on the alloy composition. When the insulation time was 10 min the maximum temperature was 1150 °Cand the heating rate was 15 min, the prepared Mg-Zn alloy spherical powder exhibited a full morphology without satellite particles, uniform composition, narrow size distribution, and a volume median diameter (VMD) of 17.62 μm. The research findings provide a new production process for Mg-Zn alloy spherical powders and establish a foundation for studying the specific effects of temperature on the production of Mg-Zn alloy spherical powders using the relative vacuum method.

Electrochemical and Thermal Modeling for the Fast-Charge of Lithium-Ion Batteries with Cocurrent and Countercurrent Tab Connections and the Assessment of Li Plating

Abstract Our focus is on large-format lithium-ion batteries, used in electric vehicles today and in the foreseeable future, which are charged at high rates. In order to fully charge the battery, we employ a protocol often referred to as cc-cv (constant current followed by constant voltage). We compare and contrast results for cocurrent and countercurrent tab locations. We show how the pseudo three-dimensional (P3D) model can be used to assess temperature and current distributions and determine if Li plating is expected. We demonstrate the advantages of countercurrent tab locations to (i) obtain more uniform current and temperature distributions and (ii) lower the propensity for Li plating. Sensitivity analyses include the influence of ambient temperature and cell length. The methodology laid out in this work can facilitate rational battery-cell design and robust operation, including high-rate charging.

Stability and content of anthocyanins in Peruvian purple potato INIA 328 - Kulli Papa

The influence of temperature, extraction time and solvent ratio on the anthocyanin content extracted from Peruvian purple potatoes INIA 328 – KULLI were investigated using conventional extraction with acidified ethanolic aqueous solvent. The preservation rate (R), thermal degradation rate (k) and the half-life (t1/2) of purple potatoes anthocyanin extract at different temperatures were determined. In addition, the color change of the anthocyanin extract was examined against different pH using UV–Visible spectroscopy. The results showed an anthocyanin content of 75.71 mg/100g of fresh weight (FW) obtained by an extraction temperature of 40 °C, for 4 h and using a solvent ratio of 5 mL/g. On the other hand, thermal kinetic degradation indicates that 98 % of the anthocyanin content can be preserved for up to 6 h at 40 °C. Better results were observed by keeping anthocyanin solutions at 4 °C in the absence of light, reaching a preservation rate of 99 % after one month of storage.

Research on the sealing performance of micro-nano composite magnetic powder to liquid media with different viscosities

This paper mainly focuses on the research on micro-nano composite magnetic powder (MNC-MP) sealing liquid medium. Micro-nano composite magnetic powder and temperature-resistant magnetic powder (TR-MP) were prepared, and their magnetization curves were measured. The influence of temperature on the saturation magnetization of the TR-MP was analyzed. The results show that after heat treatment at 100 °C for 10 min, the specific saturation magnetization remains unchanged at 102.55A·m2/kg. The pressure resistance performance of the MNC-MP sealing liquids of different viscosities and the pressure change of the TR-MP sealing silicone oil were studied in the static sealing test. The results show that the higher the viscosity of the MNC-MP sealing liquid, the better the sealing performance, and pressure remains stable at 120 kPa when sealing dimethyl silicone oil. The dynamic sealing test analyzed the relationship between the pressure and rotation speed of the MNC-MP sealing silicone oil. We concluded that when MNC-MP seals dimethyl silicone oil, the effective time of the seal decreases with the increase of rotational speed, and the leakage rate after failure increases as the rotational speed increases. The changes in temperature and torque of MNC-MP and TR-MP sealing silicone oil with time at different rotational speeds were compared. Compared with MNC-MP, the temperature of the TR-MP seal can be reduced by 23.74 %, and the friction torque can be reduced by 17.58 %.

Large amplitude voltage oscillations during plasma electrolytic oxidation (PEO) of niobium and their correlation with the porous morphology

Plasma electrolytic oxidation (PEO) is a technique that has been widely studied to obtain thick anodic oxide coatings based on aluminum, titanium, niobium, and other valve metals. In the case of niobium oxides, they are attractive because of their properties as semiconductors, biocompatibility, and high corrosion resistance. The electrochemical behavior during this process can vary according to the PEO parameters and influence characteristics such as coating thickness, adherence, morphology, and crystalline structure of the oxide film. In this study, unusual voltage oscillation transients are observed during the anodization of niobium under a galvanostatic PEO regime. The niobium substrates were anodized in three different electrolytic solutions (H3PO4, KOH, and C2H2O4), and the influence of temperature on the oscillation aspects in each one was investigated. In addition, three different current densities were tested to check the effect of this parameter on voltage oscillations. Scanning Electron Microscope (SEM), Energy Dispersive Spectrometer (EDS), and X-ray Diffraction (XRD) are used to characterize the samples. The results indicate a relationship between the exposed surface area and the pore morphology during the film growth in the oscillatory regime. A simultaneous process of oxide dissolution/pore filling and the micro-discharges observed during the PEO process is proposed.

The Influence of Solar Irradiance and Temperature on The Pll-Synchronized Inverter Within Grid-Connected PV Systems

This study assesses the influence of solar irradiance and temperature on αβPLL synchronized inverters by investigating their intricate relationship within grid-connected PV systems. The intermittent nature of the DC side of these systems can significantly impact their performance. However, the extent of this impact remains uncertain when employing the stationary reference frame PLL (αβPLL) algorithm for synchronization with the utility grid. Employing simulation in MATLAB 2020a and a Model Based Design approach in the Simscape toolbox of SIMULINK, we conducted this investigation through two test scenarios: one with constant solar irradiance and varying temperature, and the other with varying solar irradiance and constant temperature. Our results indicate that fluctuations in solar irradiance and temperature have minimal effects on the output parameters of grid-connected PV systems when synchronized with the stationary reference frame PLL (αβPLL) algorithm. This conclusion is supported by the total harmonic distortion values, which all fall within the specified limits of IEEE Standard 929- 2000. These findings underscore the potential of αßPLL synchronization as a promising technique, capable of effectively synchronizing grid inverters even in the presence of DC input distortion. This proficiency in grid integration holds promise for enhancing the integration of renewable energy sources into the grid, thereby bolstering power availability for household distribution.

Exploring the evolution mechanisms of indentation and scratching on diamond structural transformation based on molecular dynamics

Diamond, possessing high hardness and chemical stability, finds wide-ranging applications across various industries. However, during the friction process, a graphitization phenomenon may occur, which changes the mechanical properties of the diamond. In this study, molecular dynamics simulation was performed using SiC ball to investigate the influence of indentation depth and temperature on the graphitization transition of the diamond surface. The results showed that the dominant factor affecting the sp2 hybridization ratio during the indentation process was stress, while the temperature was the dominant factor during sliding. The results of this study can be used to understand the friction and wear behavior of diamonds and SiC ball and provide theoretical references for the industrial application of diamonds.

Convective heat transfer into moving fluid from a heated prolate spheroid

A common assumption in heat transfer models that involve fluid-solid interactions is that solid particles have a spherical shape. However, in numerous engineering applications, it is crucial to gain insights into the heat transfer mechanisms involving non-spherical particles and flowing fluids. These processes often employ particles with altered shapes, such as elongated geometries resembling prolate spheroids.A numerical study of airflow past a stationary constrained prolate spheroid under forced convective heat transfer is performed. A large temperature difference of the spheroid's surface was maintained relative to free stream temperature. Navier-Stokes and energy equations were solved to investigate the impact of Reynolds number (Re) and aspect ratio (AR) on convective heat transfer rate and Nusselt number (Nu). We focus on a wide range of spheroids' surface temperatures up to 1500 K in our study, which has never been studied in depth before. The simulations show that the mean Nu has a positive dependence on Ts, AR, and Re.A new correlation has been introduced that calculates the average Nusselt number (Nu) for spheroidal particles without assuming an isothermal condition (where the surface temperature Ts is roughly equal to the ambient temperature T∞). The suggested correlation incorporates the influence of AR, surface temperature, and Re.

Nitrogen-Doped Porous Carbon Derived from Covalent Triazine Framework for Catalytic Oxidation of Benzyl Alcohol.

The catalytic oxidation of alcohols is an important transformation in the chemical industry. Carbon materials with a large surface area and N doping show great promise as metal-free catalysts for the reaction. In this study, a rich N-containing covalent triazine framework polymerized by cyanuric chloride and p-phenylenediamine was used to synthesize N-doped porous carbon with the assistance of a pore-forming agent-NaCl. First, the mass ratio of the polymer/NaCl was optimized to 1:9. Then, the influence of the pyrolysis temperatures (700-1000 °C) on the materials was studied in detail. It was found that the carbon materials were gradually exfoliated by molten salt at high temperatures. XRD and Raman characterizations showed them with a certain graphitization. The optimal doped carbon CNN-1-9-900 achieved the highest surface area of 199.03 m2g-1 with the largest pore volume of 0.29 cm3g-1. Furthermore, it had a high N content of 9.9 at% with the highest relative proportion of pyridinic/graphitic N. Due to the synergistic effect between the surface area and pyridinic/graphitic N, CNN-1-9-900 showed the best performance for benzyl alcohol oxidation with TBHP at moderate conditions, and the process also worked for its derivatives.

Research on the Solid-Liquid Composite Casting Process of Incoloy825/P110 Steel Composite Pipe.

Bimetallic composites have a wide range of application prospects in various industries. Different bonding temperatures, as one of the influencing factors, directly affect the bonding effectiveness as well as the performance and application of the materials. Using metallurgical bonding techniques ensures a strong bond at the interface of bimetallic materials, resulting in high-quality composite pipe billets. This paper describes an Incoloy825/P110 steel bimetal composite material made by the solid-liquid composite method. By utilizing ProCAST 14.5 software for simulation and deriving theoretical formulas, an initial range of temperatures for bimetallic preparation has been tentatively determined. And this temperature range will be utilized for on-site experiments to prepare bimetallic samples. After the preparation process is completed, samples will be selected. The influence of the external mold temperature on the interface bonding of Incoloy825/P110 steel solid-liquid composite material is studied using an ultra-depth three-dimensional morphology microscope and a scanning electron microscope. Through research, the optimal preheating temperature range for the solid-liquid composite outer mold of Incoloy825/P110 bimetallic composite material has been determined. The casting temperature of the inner mold has a significant impact on the interface bonding of this bimetal composite material. As the casting temperature of the inner mold increases, the interface thickness gradually increases. At lower temperatures, the interface thickness is lower and the bonding is poorer. At higher temperatures, melting may occur, leading to coarse grains at the interface. When the temperatures of the inner and outer molds are within a certain range, a new phase appears at the interface. Indeed, it increases the strength of the interface bonding. Due to co-melting of the bimetal near the interface, element migration occurs, resulting in increased Ni and Cr content at the interface and enhanced corrosion resistance.

Thermal and aerodynamic characteristics of air cooled condenserfor steam turbine power unit

THE PURPOSE. Increased water consumption at power plants leads to a deterioration of the environmental situation not only in countries with limited water supply sources, but also in countries with significant reserves of fresh water. There is a need to consider the possibility of using an air condenser as an alternative use in industrial water supply systems at a power plant. To present a methodology for calculating the main characteristics of a condenser (condensation and reflux sections), to estimate the aerodynamic resistance and fan power for an air-cooled condenser as part of a steam turbine power unit. Determine the influence of air temperature and pressure in the condenser on the calculation of the air condenser. To develop recommendations for the selection of parameters of air condensers operating as part of steam turbine power units. METHODS. Methods for designing heat exchangers, modeling and intensifying heat exchange processes were used in the course of calculating an air condenser unit. RESULTS. A method for calculating an air-cooled condenser for a 110 MW condensing turbine has been developed. The analysis of the calculation of the heat transfer coefficient is given. The analysis of the values of the heat exchange area of the condensing unit is presented. The effect of pressure in the condenser on the main calculated characteristics of the condenser is shown. Recommendations for the selection of the fan capacity in the condenser and the design temperature of the cooling air have been developed. CONCLUSION. The issue of using air coolers in the power industry is still poorly covered in the literature, however, environmental problems and the shortage of fresh water are becoming more and more urgent all over the world. The development of air-cooling systems is a very topical issue for modern power engineering. It is shown that for stationary installations of condensation of water vapor, the most suitable is the hipped-roof arrangement of the heat-exchange sections with the lower arrangement of the fans. Quantitative estimates of the change in the heat transfer coefficient and the area of the heat-exchange surface are given for the pressure range of 8…20 kPa. The power consumption of the fan depends significantly on the temperature of the cooling air and the vacuum in the condenser.

Electrothermal Model Based Remaining Charging Time Prediction of Lithium-Ion Batteries against Wide Temperature Range

Battery remaining charging time (RCT) prediction can facilitate charging management and alleviate mileage anxiety for electric vehicles (EVs). Also, it is of great significance to improve EV users' experience. However, the RCT for a lithium-ion battery pack in EVs changes with temperature and other battery parameters. This study proposes an electrothermal model-based method to accurately predict battery RCT. Firstly, a characteristic battery cell is adopted to represent the battery pack, thus an equivalent circuit model (ECM) of the characteristic battery cell is established to describe the electrical behaviors of a battery pack. Secondly, an equivalent thermal model (ETM) of the battery pack is developed by considering the influence of ambient temperature, thermal management, and battery connectors in the battery pack to calculate the temperature which is then fed back to the ECM to realize electrothermal coupling. Finally, the RCT prediction method is proposed based on the electrothermal model and validated in the wide temperature range from − 20 ℃ to 45 ℃. The experimental results show that the prediction error of the RCT in the whole temperature range is less than 1.5%.