Effect Of Ambient Temperature Research Articles

Experimental study of explosion parameters of hybrid mixture caused by thermal runaway of lithium-ion battery

The explosion characteristics of the runaway battery vented gas (BVG) was studied using an 8 L column type device. The effects of ambient temperature, turbulence condition, and graphite dusts-ejected along with the BVG on the explosion process-were investigated. At 25 ℃, the explosion limits of pure BVG, the maximum explosion pressure (Pmax), and the maximum rate of explosion pressure rise (dP/dt)max is 10.8–45.8% by volume, 0.62 MPa, and 37.6 MPa/s, respectively. At 80 ℃, the three parameters changed to 10.4%− 46.5%, 0.49 MPa and 35.5 MPa/s. Moreover, these three parameters changed to 10.2–47.5%, 0.45 MPa and 33.3 MPa/s at 120 ℃. The increase in temperature reduced Pmax of BVG. While turbulence had little effect on the explosion pressure of BVG, it has significantly affected the dP/dt value. Adding graphite dusts helps BVG get to Pmax at a much lower volume concentration. As temperature increased, this effect became greater. Also, the graphite dusts can reduce the time of BVG to attain the Pmax value after igniting – the maximum reduction is from 325 ms to 158 ms. As ambient temperature increased, the combustible gas molecules were reduced, resulting in a lower Pmax value. The heat released from the BVG explosion drives the graphite involving dust explosion when oxygen is excessive. The above findings can provide a reference for the prevention of environmental explosions caused by the thermal runaway of lithium-ion batteries in process industry.

The associations of ambient fine particles with tuberculosis incidence and the modification effects of ambient temperature: A nationwide time-series study in China

Ambient fine particulate matter (PM2.5) is a major air pollutant that poses significant risks to human health. However, little is known about the association of PM2.5 with tuberculosis (TB) incidence, and whether temperature modifies the association.This study aimed to explore the association between ambient PM2.5 exposure and TB incidence in China and the modification effects of temperature. Weekly meteorological data, PM2.5 concentrations, and TB incidence numbers were collected for 22 cities across Mainland China, from 2011 to 2020. A quasi-Poisson regression with the distributed lag non-linear model was used to assess city-specific PM2.5-TB associations. A multivariate meta-regression model was then used to pool the city-specific effect estimates, at the national and regional levels. A J-shaped PM2.5-TB relationship was observed at the national level for China. Compared to those with minimum PM2.5-TB risk, people who were exposed to the highest PM2.5 concentrations had a 26 % (RR:1.26, 95 % confidence interval [CI]: 1.05, 1.52) higher risk for TB incidence. J-shaped PM2.5-TB associations were also observed for most sub-groups, however, no significant modifying effects were found. While a trend was observed between low temperatures and increased exposure-response associations, these results were not significant. Overall, approximately 20 % of TB cases in the 22 study cities, over the period 2011–2020, could be attributed to PM2.5 exposure. Strengthening the monitoring and emission control of PM2.5 could aid the prevention and control of TB incidence.

Hygroscopicity of coal powders with different ranks

The hygroscopicity of coal powder is one of the crucial factors that determine its moisture content, which significantly affects its adhesion, flowability, charge properties, and combustion behavior. In this study, the effects of coal particle size, ambient temperature, and relative humidity on the hygroscopicity of coal powders with different ranks were investigated through experimental methods. The results indicated that an increase in coal particle size resulted in a moderate reduction in the maximum moisture adsorption capacity and a substantial increase in the effective moisture adsorption time of the coal powder. As the coal particle size increased from 19 to 21 μm to 6310–6941 μm, the maximum moisture adsorption capacities of the coal powders decreased by 0.28–0.54 times, while their effective moisture adsorption times increased by 1.47–1.68 times. The maximum moisture adsorption capacities of the coal powders increased dramatically with increasing ambient relative humidity, whereas the impact of temperature on their maximum moisture adsorption capacities was not significant. The hygroscopicity of coal powders varied significantly among different ranks. Low-rank coal such as lignite and subbituminous showed strong moisture adsorption ability, while high-rank coal such as anthracite exhibited moderate moisture adsorption ability, and middle-rank coal such as medium volatile bituminous showed the weakest moisture adsorption ability. FTIR spectra analysis and pore testing results revealed that the content of oxygen-containing functional groups and the distribution characteristics of internal pores were critical factors causing the difference in hygroscopicity of the coal powders. The practical value of this study lies in its potential to determine the moisture adsorption rate and the maximum moisture adsorption capacity of coal powder under specific environmental conditions, which is essential for evaluating the moisture status, transportation efficiency and combustion performance of coal powder.

Numerical and experimental research on electromagnetic-thermal and leakage defects characteristics of the high voltage cable terminal

Thermal and insulation performance of the High Voltage Cable Terminal (HVCT) could effectively improve the reliability and economy of power energy transmission. In this paper, a numerical model of the electromagnetic heat flow field was proposed to analyze the heat transfer and temperature characteristics of HVCT under oil leakage defects. This model was the first validated using operation data from the actual equipment and the relative error was less than 1.51%. The effects of oil leakage fault on the global and local temperature distribution of the HVCT were then investigated under different load currents. In addition, the local temperature rise effect of different ambient temperatures on the HVCT oil leakage defect was also considered. Finally, combined with reference indicators such as oil level, temperature, and temperature gradient, a qualitative and quantitative evaluation of the oil leakage fault of HVCT was performed. The results showed that the temperature of the core, surface, and their maximum temperature gradient were linearly related to the ambient temperature. However, the temperature of the core at the oil leak exceeded the normal temperature by up to 7.2 °C with 1000A load current, and the temperature gradient change reaches 681.3 °C/m, which indicated that the convection heat dissipation effect of the oil-deficient part was poor, and the heat accumulates near the cable core. Therefore, the numerical model and analytical results presented in this paper provided an important method for online temperature monitoring and fault analysis of HVCTs.

Effect of Fluid Flow Direction on Intravitreal Injections of Drugs into Eye

The amount of drug in the eye depends on various factors such as genetics, layers structure, temperature distribution, and aqueous humor flow field. The heat transfer, fluid flow field, and drug delivery in the eye are numerically simulated using a three-dimensional model. The results are compared with experimental data on human and rabbit eyes. The effect of ambient temperature on the flow field in standing and supine positions was investigated. Then the transfer of drug concentration by intravitreal injection method was simulated using the obtained flow field. The results showed that the temperature distribution and the position of the eye relative to the direction of gravity have a significant role in the process of concentration transfer in the anterior segment of the eye. The results showed that in an intravitreal injection method, the drug has a significant concentration in the posterior part of the eye. In the intravitreal injection method with the injection of 1.25 mg of the drug, the maximum concentration in the vitreous humor is 1575.5 μg/ml, and the drug vanishes into the eye after 30 days. In this case, the maximum drug concentration in the aqueous humor is 30.16 μg/ml, which occurs after 1.5 days.

Investigating the effects of first idle time and ambient temperature on real driving emissions of passenger cars

Investigating the effects of first idle time and ambient temperature on real driving emissions of passenger cars

Ambient Temperature Effects on the Spring and Autumn Somatic Growth Trajectory Show Plasticity in the Photoneuroendocrine Response Pathway in the Tundra Vole.

Seasonal mammals register photoperiodic changes through the photoneuroendocrine system enabling them to time seasonal changes in growth, metabolism, and reproduction. To a varying extent, proximate environmental factors like ambient temperature (Ta) modulate timing of seasonal changes in physiology, conferring adaptive flexibility. While the molecular photoneuroendocrine pathway governing the seasonal responses is well defined, the mechanistic integration of nonphotoperiodic modulatory cues is poorly understood. Here, we explored the interaction between Ta and photoperiod in tundra voles, Microtus oeconomus, a boreal species in which the main impact of photoperiod is on postnatal somatic growth. We demonstrate that postweaning growth potential depends on both gestational and postweaning patterns of photoperiodic exposure, with the highest growth potential seen in voles experiencing short (8 h) gestational and long (16 h) postweaning photoperiods-corresponding to a spring growth program. Modulation by Ta was asymmetric: low Ta (10 °C) enhanced the growth potential of voles gestated on short photoperiods independent of postweaning photoperiod exposure, whereas in voles gestated on long photoperiods, showing a lower autumn-programmed growth potential, the effect of Ta was highly dependent on postweaning photoperiod. Analysis of the primary molecular elements involved in the expression of a neuroendocrine response to photoperiod, thyrotropin beta subunit (tshβ) in the pars tuberalis, somatostatin (srif) in the arcuate nucleus, and type 2/3 deiodinase (dio2/dio3) in the mediobasal hypothalamus identified dio2 as the most Ta-sensitive gene across the study, showing increased expression at higher Ta, while higher Ta reduced somatostatin expression. Contrastingly dio3 and tshβ were largely insensitive to Ta. Overall, these observations reveal a complex interplay between Ta and photoperiodic control of postnatal growth in M. oeconomus, and suggest that integration of Ta into the control of growth occurs downstream of the primary photoperiodic response cascade revealing potential adaptivity of small herbivores facing rising temperatures at high latitudes.

Performance Investigation on a Double-Slope Passive Solar Desalination System Targeting towards Sustainable Development of Oman

In recent times, academicians and scientists have developed many methods for purifying saline water into pure water that is suitable for drinking, as well as other suitable applications. Fortunately, solar desalination has been a very popular technique, which uses eco-friendly solar energy. In this work, a passive-type double-slope solar still was designed and fabricated according to the Global Positioning System (GPS) coordinates of Nizwa city in Oman. Economically and readily available materials, such as acrylic, glass, and foam insulation materials, were used in the construction of the double-slope solar still in addition to the conventional materials used for the supporting structure of the solar still. The climatic factors (such as the solar radiation and ambient temperature), design factors (such as the exposure surface area, inclination, insulation material and thickness, and glazing material), and operating parameters (such as the glass temperature, feed water temperature and yield) obtained were considered in the study to estimate the performance of the solar still. DHT 11 sensors with Arduino programming were used in the experiment to record the temperatures at specific locations on the solar still daily with regular time intervals for a period of 3 to 4 weeks. The solar still was designed to operate from February to March 2023. The temperatures were recorded every two hours daily, whereas the yield was recorded at the end of the day of operation. The quality of the yield was estimated through the measurement of pH and TDS (Total Dissolved Solids) values. The energy and exergy analysis of the desalination unit was carried out to estimate the thermal performance of the system. A significant effect of solar intensity and ambient temperature was observed on the thermal performance of the system and on the quality of the drinking water. An energy efficiency ranging between 30 to 45% and exergy efficiency ranging between 2 to 3.5% was obtained in the system, which was reasonably better for a thermal system involving a renewable source of energy.

Effects of ambient temperature and wind speed on icing characteristics and anti-icing energy demand of a blade airfoil for wind turbine

The icing on wind turbines causes liability issues in cold and humid climate regions with extreme climatic conditions. Accordingly, in this study, numerical simulation is employed to investigate the icing characteristics and anti-icing energy demand of a blade airfoil for wind turbines under various icing conditions. The findings indicate that the distribution range of ice accretion at 268 K is broader than that at 253 K. The maximum water film thickness experiences a significant increase at 6–8 m/s, while exhibiting a slight change at 8–14 m/s for an ambient temperature of 268 K. As the wind speed rises (6–14 m/s), the maximum heat flux demanded for anti-icing increases by 2717 W/m2 and 745 W/m2 for 253 K and 268 K, respectively. The heat flux demanded for anti-icing on the positions (0–0.02 m) of the blade airfoil declines sharply, as the latent heat released by solidification elevates the blade surface temperature. The heat flux demanded for anti-icing on the positions (0.06–0.18 m) of the blade airfoil rises at 6–8 m/s and diminishes at 14 m/s due to the change in growth rate of water film caused by airflow. This research contributes to the development of anti-icing method design for wind turbines.

Effects of ambient temperature on locomotor activity and place conditioning elicited by abused psychostimulants in mice: Role of 3,4-methylenedioxy moiety

BackgroundHumans often administer psychostimulants in party or music festival settings characterized by warm ambient temperatures, which may impact drug effects; however, preclinical studies rarely investigate drug effects at multiple ambient temperatures. Work with 3,4-methylenedioxymethamphetamine (MDMA) and 3,4-methylenedioxypyrovalerone (MDPV) suggests that the presence of a 3,4-methylenedioxy ring moiety may influence ambient temperature-dependent effects. MethodsLocomotor activity and conditioned place preference dose-response curves were generated at 20±2°C for two amphetamine analogues (MDMA and methamphetamine [METH]) and two cathinone analogues (MDPV and α-pyrrolidinopentiophenone [αPVP]) in mice. Effects were then redetermined at 29±2°C for each drug and assay. ResultsAll four drugs elicited dose-dependent locomotor stimulation at the cool ambient temperature. At the warm ambient temperature, MDMA and MDPV produced sensitization to stereotypy, whereas METH and αPVP produced sensitization to locomotor activity. Regarding place conditioning, the warm ambient environment potentiated place preference elicited by doses of METH and αPVP that were sub-threshold in the cool ambient environment, but attenuated the effects of analogous doses of MDMA and MDPV. ConclusionsThese studies suggest that warmer ambient temperatures may potentiate typical stimulant effects for the drugs lacking the 3,4-methylenedioxy ring, but may potentiate the behaviorally toxic/adverse effects for the drugs containing a 3,4-methylenedioxy ring. Thus, preclinical abuse liability studies conducted at standard laboratory temperatures may not fully capture the effects of psychostimulants and highlight the need to model the environments in which drugs are typically used by humans.

Short-term effects of air pollution and weather changes on the occurrence of acute aortic dissection in a cold region.

Air pollution and severe weather conditions can adversely affect cardiovascular disease emergencies. Nevertheless, it remains unclear whether air pollutants and low ambient temperature can trigger the occurrence of acute aortic dissection (AAD) in cold regions. We applied a retrospective analysis to assess the short-term effects of air pollution and ambient temperature on the occurrence of AAD in Harbin, China. A total of 564 AAD patients were enrolled from a major hospital in Harbin between January 1, 2017, and February 5, 2021. Weather condition data and air pollutant concentrations, including fine particulate matter smaller than 10 μm (PM10) and 2.5 μm in diameter (PM2.5), nitrogen dioxide (NO2), sulfur dioxide (SO2), carbon monoxide (CO), and ozone (O3), were collected every day. Conditional logistic regressions and correlation analysis were applied to analyze the relationship of environmental and atmospheric parameters with AAD occurrence at lags of 0 to 7 days. Specifically, we appraised the air quality index, CO, NO2, SO2, O3, PM10, PM2.5, temperature, dew point temperature, atmospheric pressure, and cloud amount. A total of 1,496 days at risk were assessed, of which 564 patients developed AAD. Specifically, AAD did not occur on 1,043 (69.72%) days, while 1 or more cases occurred on 453 (30.28%) days. Several pollution and weather predictors for AAD were confirmed by multilevel modeling. The air quality index (p = 0.0012), cloud amount (p = 0.0001), and concentrations of PM2.5 (p = 0.0004), PM10 (p = 0.0013), NO2 (p = 0.0007) and O3 (p = 0.0001) predicted AAD as early as 7 days before the incident (lag of 7 days) in the study period. However, only concentrations of the air pollutants NO2 (p = 0.0468) and O3 (p = 0.011) predicted the occurrence of AAD after the COVID-19 outbreak. Similar predictive effects were observed for temperature, dew point temperature, and atmospheric pressure (all p < 0.05) on all days. The risk of AAD is closely related to air pollution and weather characteristics in Harbin. While causation was not determined, the impact of air pollutants on the risk of AAD was reduced after the COVID-19 outbreak.

The effect of ambient outside temperatures on scoop stretchers

Background: Scoop stretchers are commonly used in the prehospital care of trauma patients. Patients' clothing is often removed early in the care pathway. There may be unidentified risks if scoop stretchers are particularly cold. Aims: The primary aim of this research was to establish if there is a positive correlation between scoop temperatures and outside temperatures when this equipment is stored without access to vehicle heating. Methods: The authors recruited volunteers at ambulance locations across Scotland to measure scoop temperatures using infrared thermometers. These were compared to outside temperatures at that time. Data were subject to bivariate quantitative analysis to assess correlation strength. Findings: Results demonstrated that there was a moderate-to-strong correlation between scoop temperatures and outside temperatures (mean +3.0°C; P&lt;0.001). There was no significant difference for other variables measured. Conclusion: Without active heating, scoop stretchers will be only marginally warmer than the outside temperature, sometimes colder than the outside temperature and sometimes below freezing point.

Thermal Runaway Behaviors and Kinetics of NCM Lithium-Ion Batteries at Different Heat Dissipation Conditions

The lithium-ion battery (LIB) thermal runaway is triggered by the exothermic reactions between electrode materials and other active substances such as electrolytes. In this study, the effects of ambient temperature and heat transfer coefficient on the thermal responses and chemical kinetic features of LiNi1/3Co1/3/Mn1/3O2/graphite battery thermal runaway at high-temperature abuse conditions are investigated using a validated 2D axisymmetric model. With varied heat transfer coefficients of the LIB, the corresponding runaway, critical, and safety operation zones at different ambient temperatures are quantitatively distinguished. The results reveal that, with increased heat transfer coefficient, the critical ambient temperature, T c, triggering thermal runaway increases. However, T c almost remains 430 K when the heat transfer coefficient is higher than 25 W/(m2K). Additionally, based on the thermal response of LIB, the ambient heat absorption stage, ambient heat dissipation stage, and dramatic heat release stage in thermal runaway are defined. It is found that a higher heat transfer coefficient efficiently causes a shorter ambient heat absorption stage, which is the primary reason for the reduced delay time for the thermal runaway. Further, kinetic analysis is conducted at different heat exchange conditions, and the correlation between LIB thermal responses and the heat release of side reactions in different operation zones is clarified. Specifically, the reactions between the electrolyte and negative/positive electrodes are the most exothermic and most influential of all side reactions, and their influence on the maximum temperatures and runaway delay times is promoted with an elevated heat transfer coefficient.

Finite element modeling of early-age temperature development of in-situ concrete under variable ambient temperatures

The early-age temperature rises in in-situ concrete, caused by the exothermic hydration of cement, poses a significant risk of thermal cracking in concrete structures. This issue is particularly critical in large-scale structures, where thermal cracking can lead to serious structural integrity issues. Therefore, the accurate prediction of the concrete hydration temperature development is paramount for predicting and mitigating early thermal cracking in concrete. However, one of the main challenges in predicting in-situ concrete temperatures is the significant effect of variable ambient temperature on cement hydration rates and concrete heat dissipation. To address this challenge, this paper presents a finite element modeling (FEM) approach that accurately predicts the early-age temperature development of in-situ concrete by adequately considering the effect of variable ambient temperatures. The model integrates the heat of hydration of the cement, the impact of ambient temperature variations, and the heat transfer through the concrete and insulation mould. The cement hydration rate under real-life ambient temperatures is simulated using an Arrhenius-based method, which mathematically adjusts the isothermal calorimetry curves to reflect the actual conditions. Additionally, the study investigates the inhibitory effect of Ground Granulated Blast-furnace Slag (GGBS) on the early hydration temperature of concrete, with experimental tests and FEM simulations conducted on concrete mixes where up to 70% of the cement was replaced with GGBS. The validity of the FEM model was confirmed through comparison with concrete semi-adiabatic tests, demonstrating that the model provides accurate predictions of the temperature development of in-situ concrete. Importantly, the results indicate that the adjusted isothermal calorimetry curves successfully capture the ambient temperature effect on the cement hydration rate. The results provide valuable insights for the design of concrete structures, particularly in preventing early-age thermal cracking.

The effect of soil moisture and ambient temperature on pupation depth for the imperiled Callophrys irus

The effect of soil moisture and ambient temperature on pupation depth for the imperiled Callophrys irus

Effect of metabolite and temperature on artificial human sweat characteristics over a very wide frequency range (400 MHz–10.4 GHz) for wireless hydration diagnostic sensors

Sweat is an important biofluid that is excreted by the human body. It contains physiological biomarkers that provide vital information on the general health condition of the body. As a result, analysis of electrolytes in this biofluid is gaining traction in the development of non-invasive sweat diagnostics to determine level of dehydration, cystic fibrosis and illicit drugs. This paper presents a wireless measurement modality of permittivity properties of sweat of different metabolite concentration levels exemplifying the full spectrum of human sweat. The artificial sweat used in the study is an analogue of actual human sweat. It is synthesized from a composite mixture of metabolites and minerals including sodium chloride, potassium chloride, Urea and lactic acid. The effect of ambient temperature on the permittivity measurements of the various sweat solutions are studied across a frequency range of 400 MHz to 10.4 GHz. This information is important in the development of wireless radio frequency (RF) non-invasive biosensors.

Growth performance and carcass characteristics of Koekoek chickens exposed to temperature variation with supplementary Coriander seed powder

The aim of the present study was to evaluate the effects of ambient temperature and coriander seeds supplementation on growth performance and carcass characteristics of Koekoek chickens. In the experiment, chickens were exposed to two temperature rooms with a heated room of 32 ± 1.2 °C from 11:00 to16:00 h and a normal room temperature with an average maximum and minimum of 23.8 ± 3 °C and 16.6 ± 1.6 °C, respectively, and a relative humidity between 34.5 ± 4 and 44.8 ± 3%. The chickens were supplemented with 0, 5, and 10 g/kg of coriander seed powder. The results showed that the group of Koekoek chickens placed in a heated room had significantly lower (P < 0.05) feed intake and weight gain and significantly higher (P < 0.05) feed conversion ratio than the groups placed at normal room temperature. Water intake was 1.8% higher in the groups placed in a heated room than those placed at normal room temperature. Supplementation with coriander seed powder enhanced growth performance and carcass traits. The carcass weight and breast percentage were higher (P < 0.05) in the groups that received 10 g/kg coriander seed powder. The growth performance of the Koekoek groups supplemented with 10 g/kg coriander seed powder in a heated room also improved significantly compared to groups in a heated room without supplementation. This suggests that the supplementation of coriander seed improves performance, and has a positive potential effect in alleviating the negative effects of heat stress on growth performance of chickens.

Investigation of Analog/RF and linearity performance with self-heating effect in nanosheet FET

In vertically stacked gate-all-around Nanosheet FET (NSFET), the channels/sheets are wrapped by a low thermal conductivity material, which hinders the active heat flow path and, thus, raises reliability concerns. Therefore, the role of temperature, i.e., ambient condition and self-heating effect (SHE), become prime objectives that must be adequately addressed. In this work, through extensive TCAD simulations, we analyzed the DC/Analog/RF/Linearity characteristics of an NSFET, considering the cumulative effect of ambient temperature and SHE. Using well-calibrated TCAD models, we investigated: (i) the variation in device characteristics with and without considering SHE; (ii) the impact of SHE and ambient temperature on Analog/RF and Linearity characteristics using well-defined figure-of-merits (FoMs); (iii) the device optimization, i.e., the significance of the varying number of sheets (Nsheet) with considering SHE for optimal performance; (iv) the impact of varying temperature over the voltage gain of an NSFET-based common source (CS) amplifier considering SHE. The temperature variation (including SHE) significantly affects the ON current (e.g., reduced by 9.4%), resulting in the modulation in transconductance (gm). Therefore, the designed CS amplifier's gain is also altered by temperature variation (e.g., ranging from 250 K to 400 K). Hence, the proposed analysis is worth exploring to acquire the design guidelines for optimal and reliable DC/Analog/RF/Linearity characteristics of a Nanosheet transistor under various temperature conditions.

Evaluating the correlation of blood pressure and pulse rates of firefighters with their sociodemographic characteristics during a fire and rescue training

Introduction: Cardiac strain has become a prevalent cause of firefighters’ death. Standards and regulations set forth a framework to monitor the cardiovascular fitness of firefighters, encourage fitness and create a pathway to diagnosis or detection of disorders. The effectiveness of these standards relies on continuous evaluation of firefighters’ health and updating the protocols. Methods: This study intended to assess the physiological response of 172 firefighters in the middle east for the first time and considered the effect of body mass index, age, gender, and seasonal ambient temperature on their responses before and after a fire and rescue training. The end results should compile the behavioral patterns of firefighters from the region and help authorities to update current health monitoring standards for firefighters accordingly. Blood pressure, heart and respiratory rates were sampled for participants after one minute after when training finished. Non-Parametric statistical analysis was conducted using Nonparametric Spearman rank correlation coefficients and Kruskal-Wallis H- test to evaluate the correlation of age, gender, BMI, and seasonal temperature with participant’s physiological response. Results: This study found obesity in 20% of the sampled population with more cases among male participants. Also, in this study, the hypertension prevalence ratio found as 19.8% at baseline and 26.7% in post-training measurements. Conclusion: This study could confirm that body mass index and seasonal ambient temperature affect blood pressure, heart and ventilation rates. Heart rate significantly changes with ambient temperature. Also, the results found the gender of participants affects all physiological responses, especially heart rate.

Single-phase static immersion cooling for cylindrical lithium-ion battery module

The single-phase immersion cooling is an emerging technology for battery thermal management. Both static- or forced-flow working fluids can be adopted, while the advantages of the static mode are less complexity and low cost. This work proposes a static flow-based immersion cooling method for a six-cell cylindrical Li-ion battery module. The effectiveness of the proposed immersion cooling system is studied at different current rates and compared with conventional air-cooling methods. Experiments find that the maximum cell temperature (Tmax) appears at the end of discharge, and it increases with the C-rate. The proposed immersion cooling system can limit the Tmax below 40 °C and temperature gradient within 3 °C at 3C discharge, exhibiting a superior cooling capability over air cooling. The three-dimensional numerical model has been established to further analyze and optimize the performance of the proposed immersion cooling system. Modelling suggests that immersion cooling has a maximum cooling rate of 2.7 W for the cell with the highest temperature, which is 50 % higher than the cooling rate of the forced air-cooling system. In addition, the effects of ambient temperature and liquid volume have been numerically investigated. Different cooling regions are defined to evaluate the thermal-management performance of the immersion cooling system. Finally, the cooling efficiency of three different fluids is compared in a 100-cell battery module, which can provide valuable information for battery thermal management and scientific guidelines for applying immersion cooling for batteries in operation.