Varying Flow Rates Research Articles

Optimization of Heat Transfer Performance Using Response Surface Methodology-Central Composite Design (RSM-CCD) for Nano-Coolant (Al2O3+EG/W) in Electric Vehicle Battery

The presence of electric vehicles (EVs) must be supported by batteries that have good-quality energy storage. Battery power is critical to the development of electric cars. Temperature affects battery strength, so operating within the optimum temperature range must be ensured. During the charge and discharge processes, the electrochemical reaction generates hot energy, causing an increase in battery temperature. In this research, the solution to the problem is to make a cooling system with a mini channel cold plate and Al2O3 1%vol+EG/W (50:50) nano coolant. Optimization of heat transfer enhancement using Response Surface Methodology-Central Composite Design (RSM-CCD) and experimental tests with various flow rate variations. The research findings revealed that the RSM-CCD results and the outcomes of studies employing test equipment agreed that the highest cooling fluid flow rate was the most optimal condition, the highest T2 temperature drop of 17.63% occurred at a flow rate of 1.7 LPM, and the lowest T2 temperature was 13.13% at a flow rate of 1 LPM.

The Effect Of Pitch Ratio On Screw Turbine Performance With Tip Fin

A water turbine is an energy conversion machine that converts water head into shaft movement. In screw-type turbines, performance is influenced by several parameters including outer diameter, inner diameter, rotor length, head angle, number of blades, and pitch distance. This research uses a screw turbine type with a tip fin. The research aims to determine the performance of screw turbines with tip fins on mechanical power and efficiency. The research independent variables consist of pitch ratio and flow rate. The pitch ratio variations used are 1.2; 1.4 and 1.6 while the variations in flow rate used are 3 l/s, 3.5 l/s, and 4 l/s. The method used in this research is experimental. This study's data analysis employed the two-way Anova method with an alpha (α) of 5%. Anova's results show that the P-value of the interaction of the two independent variables, pitch ratio and water discharge, is <0.05, meaning that the independent variables have a significant influence on the performance of the screw turbine. The highest turbine performance results were at a pitch ratio of 1.4 at a water flow rate of 4 l/s resulting in an efficiency value of 34.91% and a mechanical power value of 6.82 watts at a rotational speed of 125 RPM. The lowest turbine performance results at a pitch ratio of 1.2 with a flow rate of 3 l/s resulting in an efficiency of 22.64% and a mechanical power of 3.32 watts at a rotational speed of 56 RPM.

Integrated photovoltaic-thermal system utilizing front surface water cooling technique: An experimental performance response

In the realm of photovoltaic-thermal (PVT) systems, optimizing operating temperatures for photovoltaic (PV) panels is a challenge. This study introduces a novel solution: a sprayed water PVT system that simultaneously harnesses energy and electricity. The aim is twofold: generate electricity through PV panels and produce hot water via a flat plate collector, using an innovative cooling mechanism. Water sprayed onto the PV panel's surface flows to a collector for storage. With varied flow rates, optimal panel efficiency occurs at a 45⁰ tilt angle, accompanied by lower collector outlet temperatures at higher flow rates. The collector achieves a peak thermal efficiency of 70.6 %, producing hot water at 84.6 °C. Notably, a significant PV panel efficiency enhancement, up to 16.78 %, especially at 1.56 L/min flow rate, is observed. The cooling technique consistently reduces panel temperatures from 45.08 °C to 34.12 °C. A self-cleaning spray mechanism improves efficiency by 2.53 %, resulting in an overall system efficiency of 83.3 %. This research offers an innovative approach to enhance energy generation and electricity in PVT systems, promising sustainable energy optimization.

THE EFFECT OF ZNO/CUO-WATER- HYBRID NANOFLUID CONCENTRATION RATIO ON HEAT TRANSFER CHARACTERISTICS IN ELECTRONIC EQUIPMENT COOLING SYSTEMS

The use of hybrid nanofluids CuO-ZnO /distilled water as a cooling medium was tested in this study to determine the characteristics of convection heat transfer. The hybrid nanofluids preparation process was carried out first by dispersing the CuO and ZnO nanofluids using an ultrasonic cleaner for 3 hours and then allowed to settle for 24 hours. Furthermore, the CuO and ZnO nanofluids were mixed based on the stipulated ration of CuO:ZnO (25%:75%), (50%:50%) and (75%:25) with a volume fraction of 0.5% and agitated for 1 hour. Testing of the hybrid nanofluids CuO-ZnO/distilled water was carried out using a water block as an electronic cooling device with a flow rate variation of 0.7 – 1.9 l/min. From experimental results, the convection coefficient, as one of performance parameters of cooling device, and its relation to Reynolds numbers was able to be determined. Overall, the results show that the rate of heat transfer with the hybrid nanofluids is higher compared to distilled water. At a particular configuration of flowrate and nanoparticle ratio, the hybrid nanofluid has more than 2.5 times higher coefficient of convection than distilled water. In addition, the experiment revealed that the synthesized nanofluid created a temperature drop of around 40ᵒC across the water block at a heater power of 10 W.

Numerical investigation of thermal-mixing characteristics at vertically oriented T-junction pipelines

When hot and cold fluids are mixed at pipeline tees, temperature fluctuations are generated and can lead to thermal fatigue damage in the piping materials. At the University of Stuttgart in Germany, experimental investigations have been performed for understanding the flow mixing mechanism causing thermal fatigue. It was found that the inlet flow rate is one of the decisive factors on the mixing behaviors at a horizontal T-junction.In this study, the influence of the inlet flow rate on the flow mixing behaviors at the vertical T-junction is investigated using the large-eddy simulation (LES) method. The simulations are validated with the previous experiments and provide a good overview of the mixing flow. The LES method shows the advantage of illustrating the collision of two flow streams at the T-junction, which leads to different behaviors of the mixing flow. Generally, the temperature fluctuation in the mixing flow as well as the stability of thermal stratification decreases along the flow direction due to the dissipation of the turbulent kinetic energy in the mixing flow. The decrease in the main flow rate shows the impact of the increase in thermal stratification stability and the reverse flow distance. The decrease in the branch flow leads to a slight increase of the thermal stratification stability downstream of the T-junction and significant turbulent penetration in the branch pipe. The maximum temperature fluctuation at the pipeline inner surface is located at the joint position of the pipelines with a value higher than 30 K. Moreover, the flow collision at the T-junction leads to significant secondary flow in the mixing region, which can be influenced by the variations in the inlet flow rate. In particular, the secondary flow due to cold fluid presents a phenomenon of counter-rotating vortex pair (CRVP), and generates a temperature fluctuation with a frequency of approximately 1.1 Hz, which is recorded by the monitor points at both horizontal sides of the pipeline. In comparison with the previous work at the horizontal T-junction, the complete flow collision at the vertical T-junction is the reason for the totally different mixing phenomenon.

Towards practical implementation of molecular communication: A cost‐effective experimental platform based on the human circulatory system

AbstractRecently, there have been numerous studies exploring the field of molecular communication (MC) systems. However, due to the high cost and limited availability of advanced micro/nano‐scale equipment, most of these works remain purely theoretical, with only a few being examined through experimental platforms. Additionally, the absence of a suitable model for flow‐assisted MC‐based systems poses another significant challenge. This research focuses on the potential applications of MC technology within the human body. To address the limitations mentioned above, a closed‐loop experimental platform based on the human circulatory system is proposed. This platform offers a cost‐effective and accessible solution for studying MC systems. The implementation process involves a brief discussion about the circulatory system model. By varying flow rates and the quantity of released information particles, channel impulse responses are obtained. Based on the observed experimental data, the authors have successfully developed a new theoretical model that accurately fits the experimental data. The model demonstrates a strong level of agreement with the observed results. This model demonstrates its suitability for flow‐assisted MC‐based systems.

Effect of steam reinjection mass flow rate on the SOFC–GT system with steam reinjection

A solid oxide fuel cell (SOFC) is regarded as the first choice of high-efficiency and clean power generation technology in the 21st century due to its characteristics of high power generation efficiency and low pollutant emission. In this paper, hydrogen is used as a fuel for SOFCs using the EBSILON platform. A sensitivity analysis of the solid oxide fuel cell–gas turbine (SOFC–GT) system with steam reinjection is carried out to investigate the effect of the steam reinjection mass flow rate on the improvement of the electrical efficiency of the system and on the values of the other parameters. The results show that the variation in the steam reinjection mass flow rate has an effect on other parameters. Changes in several parameters affect the electrical efficiency of the system, which reaches 74.11% at a pressure ratio of 10, SOFC inlet temperature of 783.15 K, turbine back pressure of 70 kPa, and steam reinjection mass flow rate of 6.16 kg/s. Future research can optimize the overall parameter selection of the system in terms of economy and other aspects.

Salt rejection/discharge strategies of a reverse-distillation device with a water layer for sustainable solar desalination: From two dimensions to three dimensions

The recently proposed solar-driven reverse-distillation device with a water layer has shown promising potential in solar energy conversion efficiency and impactful advantages in salt rejection by constructing a rapid brine flow driven by gravity/density differences. However, a lack of profound understanding and explanation of the salt-rejection mechanism and accurate salt-discharge regulation strategies may hinder the further improvement of reverse-distillation devices. In this paper, we thoroughly discuss and analyze the mechanism of how gravity affects the internal brine flow and determines the salt rejection/discharge performance while providing comprehensive salt-discharge regulation strategies for feed brine with a wide range of salinities. The results show that only a 4° inclination angle enables the two-dimensional (2D) device with a 1-mm-thick water layer in the dissolution mode to dispose 3.5 wt% brine for 8 h without salt saturation, while the value is also merely 10° for a three-dimensional (3D) device, indicating the realization of the brine flow driven by a small gravity component and demonstrating a strong adaptability for the device. In the salt discharge mode, the ratio of the discharge flow rate to the evaporation rate determines the salt saturation risk. We discuss the salinity distribution of the evaporation surface at varied feed-brine salinities and discharge flow rates, providing a theoretical basis for precisely matching the thermal characteristics and enabling improved design for efficient and sustainable solar-distillation devices. Finally, we discuss the scalability of salt rejection and propose a scheme for scalable water production, which may offer important support for further realizing large-scale sustainable solar desalination by using the reverse-distillation device with a water layer.

Experimental and numerical study on characteristics of super-linear mass flow rate and asymmetric cavitation in novel rotary-baffle curved-channel electronic expansion valve for refrigerator

Capillary tubes, as the expansion devices in refrigerators, are unable to actively match cooling capacity and load, which will increase the energy consumption. Moreover, due to the limitations of miniature valve needle machining accuracy and structural strength, orifice-type EEVs are not suitable for low mass flow rate in refrigerators. A novel rotary-baffle curved-channel electronic expansion valve (RBCC-EEV) is proposed to replace capillary tube to achieve flow regulation in household refrigerators. Based on the special structure and regulation principle of RBCC-EEV, characteristics of mass flow rate and cavitation are studied experimentally and numerically, respectively. Experimental results show that, as opening ratio (OR) increases, the synchronous changes in the inlet area and length of the curved channel lead to a super-linear variation in mass flow rate, with increase rate growth from 0.018 kg h−1 OR−1 to 0.061 kg h−1 OR−1. Numerical results show that, under centrifugal forces, the pressure difference along the normal direction of the streamline leads to the differences in degree of cavitation, which is called asymmetric cavitation phenomenon. In addition, under the influence of this phenomenon, the prematurely cavitation of refrigerant near the inside surface will block the inlet of curved channel early, resulting in a 3.4 % decrease in mass flow rate.

Dislocations/Defects analysis in III-V nitrides - a cost effective MOCVD epitaxy solution

In present paper an innovative technique to reproduce the epitaxial growth results through lateral flow metal organic chemical vapor deposition (MOCVD) reactor process at atomistic scale is reported. It includes the equivalent MOCVD reactor geometry architecture of AIXTRON 200/4 RF-S horizontal flow reactor. The gas- and surface phase chemical reaction kinetics and thermodynamics are given due consideration in the present study without use of any continuum or fluid dynamics models. The optimum conditions are extracted by running design of experiments over TNL-EpiGrow simulator to achieve high crystalline quality aluminum nitride (AlN) films over Si (111) substrate. The impact of variation in precursor NH3 flow rates and carrier gas N2 pressure are used to predict the conditions to optimize the improved morphology and quality of the AlN films. The defects densities are characterized in terms of vacancies and dislocation densities. The roughness and lattice parameters are extracted. The growth rates obtained in present studies are compared against reported the similar experiments. The excellent agreement is observed between experimental and simulated results. The dislocation densities in grown samples are also found in good agreement with the similar experimental reported densities in each sample.

Coffee Shop Liquid Waste Treatment System Using Portable Waste Water Treatment Plant (WWTP)

Coffee shops produce waste that is included in the category of domestic waste in a fairly large amount. Therefore, it is necessary to carry out domestic wastewater management. One solution is the design of an integrated portable WWTP that can treat waste from coffee shop business activities. The advantages of using WWTP are that it is simple and does not require large amounts of land. The processing of this WWTP consists of filtration and precipitation. The wastewater to be filtered will be separated from the solids, after which it will be continued with stratified filtration using activated carbon. In the study, variations in flow rate were carried out to determine processing efficiency, namely variations in tap openings of 30o, 45o, and 90owith water flow rate of 200, 360, and 570 mL/s. The result of research, the portable Wastewater Treatment Plant with activated carbon filtration designed has been able to treat coffee shop liquid waste. The variation of flow rate in the processing of coffee shop liquid waste affects the processing results where the smaller the flow rate, the greater the efficiency reduction. The optimum flow rate variation in this study is 200 mL/s with a COD removal efficiency of 48.5%, TSS 72.8%, Coliform 66.6%, TDS 62.5%, and pH 6.2. The suggestion that can be given is the addition of a biological treatment system to optimize the performance of Portable WWTP.

Experimental study on the airflow dynamics and particulate matter emission characteristics of cooking fumes during frying, roasting, and deep-frying

Clarifying the characteristics of thermal plume airflow dynamics and particle characteristics during different cooking processes is helpful for efficiently controlling cooking fumes. In this study, the flow and emission characteristics of cooking fumes produced during frying, roasting, and deep frying were investigated using quantitative schlieren techniques and particulate matter sensors. The results show that frying, roasting, and deep-frying have smaller vortex areas, but different to that produced when simply heating edible oil, with the three cooking scenarios exhibiting plume dispersion angles that are, on average, approximately 20° larger than that observed for the heated-oil case. Furthermore, the emission velocity of the source ranged from 0 to 0.5 m/s for the four cases (within a distance one-times the diameter of the emission source). The velocity of the heated-oil case was generally Gaussian distributed, whereas those of the cooking cases were parabolically distributed. All cases exhibited linear variations in sectional diffusion diameter and flow rate along the vertical direction. The three cooking cases exhibited linearly fitted slopes that are approximately 1.0–2.0-times greater than that of the heated-oil case, which is reflective of more ambient air entrained during cooking. Particles 1–2.5 μm in size were observed for the three cooking cases, while the deep-frying case exhibited an average particulate mass concentration more than twice that observed for the heated-oil, which significantly increases the danger of exposure to oil-fume particles. In summary, detailed cooking-fume data serve as boundary conditions for simulations and provide crucial insight for effectively capturing cooking fumes.

Improved VIV energy harvesting with a virtual damper–spring system

In recent years, energy harvesting systems driven by vortex induced vibrations (VIV) emerged as potential alternative to conventional rotor-based installations, in particular for low flow speeds in water. Best energy outputs are obtained when the flow-dependent VIV frequency locks in the natural frequency of the energy harvesting structure. However, placed in tidal currents or rivers with variable flow rates, the VIV frequency changes, leading to frequency mismatch with efficiency losses. In this paper, we present a new mechatronic experimental set-up to study the harvesting efficiency of a VIV driven cylinder under various flow rates. In particular, we explore options to improve harvesting efficiency by adding computer controlled virtual damping and stiffness to the mechanical system. The setup comprises an elastically mounted, single-degree-of-freedom cylinder within a low-speed water tunnel. Virtual damping and stiffness are applied by controlling the force exerted through a mechanically coupled DC motor. The experiments reveal that optimal values for damping and stiffness are consistent with previous results from the literature. The maximum energy conversion efficiency of around 18% is achieved when oscillation and vortex shedding frequencies are synchronized. The explored parameter space highlights in particular that mismatches between oscillation and vortex shedding frequency strongly decrease the achievable efficiency. By contrast, the peak efficiency is less sensitive to an increase of damping due to energy harvesting. All these observations suggest that VIV driven energy harvesting systems need a real-time structural stiffness control to maintain an economically acceptable efficiency under various flow conditions. In the near future, we plan to automate the structural stiffness control under various flow rates by testing Machine Learning algorithms with our mechatronic set-up.

Simulation of a sorption-enhanced water gas-shift pilot technology for pure hydrogen production from a waste gasification plant

This study has analysed and optimised a 5-column sorption enhanced water gas shift (SEWGS) pilot unit, set to operate for the first time in a waste gasification facility for the production of transport-grade hydrogen and CO2 streams. Full process simulation was undertaken by developing a one-dimensional model of each reactor, with boundary conditions directly informed by real plant operation. From the sensitivity analysis performed, syngas flowrate variations were seen to have a minor but temporary, impact on hydrogen product specifications, while changes to syngas composition were shown to have a longer-lasting effect on system performance. Based on full cycle operation results, the current 5-column SEWGS unit design was concluded to be inadequate for fuel-cell-grade H2 production, despite obtaining a high H2 purity of 99.5%, mainly due to its excessive steam consumption. However, the process achieved an exceptionally high CO2 purity of 99.9%, and 88.6% hydrogen recovery rate, suggesting its potential use in carbon capture and heat-grade hydrogen production applications.

Performance optimization of droplet formation and break up within a microfluidic device – Numerical and experimental evaluation

Droplet-based microfluidics, including the controlled manipulation of materials in the form of monodisperse droplets on the micrometer scale in microfluidic chips, has gained much attention due to their ability in biological assays. The capillary number of the continuous phase, as the ratio of viscous force and interfacial tension, is so important in the mechanism of droplet formation. This study aims to survey the type of continuous-phase fluid, the change in the parameters of the continuous phase, and the effect of the different flow rates ratios on the droplet formation dynamics, droplet size, distance between droplets and frequency of droplet formation. Three types of oil, including mineral, olive, and paraffin in a flow-focusing microfluidic device have been utilized numerically and experimentally. To characterize the parameters of the continuous phase affecting the droplet size, a microfluidic device has been designed to estimate of the droplet size for three different types of oil used in the assay. The results show that for a constant continuous phase velocity, the diameter of the droplets formed in olive oil has the lowest amount, followed by paraffin and mineral oil, respectively. Regarding the effects of oil type on the frequency of droplet formation and the distance between droplets, the rate of droplet formation in mineral oil, in the ratios of the variable flow rate and the constant continuous phase velocity, is the lowest and, the distance between the droplets has the highest level.

Experimental investigation of thermal performance of vertical multitube cylindrical latent heat thermal energy storage systems

The multitube design in the shell-and-tube type latent heat thermal energy storage (LHTES) system has received intensive attention due to its promising benefits in enhancing heat storage efficiency. In this paper, single and multi-tube shell LHTES systems were experimentally investigated. First, this study experimentally compared the thermal characteristics between a multiple-tube heat exchanger (MTHX) and a single-tube heat exchanger (STHX). The STHX’s geometrical parameters coincided with a virtual cylindrical domain in the MTHX, being similar to the single-tube model formulated by simplifying the numerical solution to investigate the MTHX. The experimental data was then used to validate the simplified numerical model commonly used in the literature that converted the multi-tube problem to a single-tube model by formulating a virtual cylindrical domain for each tube in the MTHX system. The results showed that there was a noticeable difference in the thermal characteristics between the actual STHX and the virtual cylindrical STHX domain in the MTHX system. The comparison indicated that the simplified numerical model could not accurately reflect the thermal performance of the MTHX system. An experimental study or three-dimensional numerical modelling was required for the thermal analysis of the multi-tube problems. Second, the effect of tube number in the MTHX was experimentally investigated. It was found that an increase in tube number boosted both charging and discharging rates without inhibiting the natural convection. The five-tube configuration decreased the total charging and discharging duration by 50% compared to the two-tube one. Finally, the effect of heat transfer fluid (HTF) operating parameters on the system performance was evaluated on the five-tube MTHX system. The results revealed that the adoption of higher HTF temperature considerably improved the charging performance. The charging time decreased by up to 41% with the HTF temperature increasing from 70 to 80 °C. Meanwhile, a variation in the HTF flow rate from 5 to 20 L/min showed a more pronounced influence on charging than on discharging due to the different dominant heat transfer mechanisms.

Microchannel cooling plates with non-uniform airfoil fin arrangement for large-capacity marine battery: An experimental study

In the process of charging and discharging, the heat generation of the battery is uneven, which is more obvious for large-capacity batteries. To maintain the performance of the battery, the thermal management system based on the cooling plate is of critical importance. In this paper, the non-uniform airfoil fins arrangement of microchannel cooling plates for marine large capacity battery thermal management are designed and tested. The cooling performances of the uniform airfoil fins arrangement (UAFA), non-uniform airfoil fins arrangement 1 (N-UAFA 1) and non-uniform airfoil fins arrangement 2 (N-UAFA 2) are experimentally investigated. The maximum temperature (Tmax) and temperature standard deviation (SD) of battery module during charge and discharge process are compared with the variation of the volume flow rate (qv), the cooling water inlet temperature (Tin) and the charge–discharge rate (CR). The experimental results demonstrate that increasing qv and decreasing Tin would contribute to lower Tmax but higher SD. Both Tmax and SD increase with the CR increasing. The cooling effectiveness of the non-uniform airfoil fins arrangement is validated by the reduced Tmax and the robustness in SD control. In particular, the newly designed N-UAFA 2 microchannel could relief the contradiction between cooling capacity and the temperature uniformity. For all the working conditions, the N-UAFA 2 exhibited the best performance. Especially at the CR of 0.5C, the N-UAFA 2 could manage the Tmax and the SD below 36.8 °C and 1.5 °C, respectively.

Improving Thermal Energy Storage in Solar Collectors: A Study of Aluminum Oxide Nanoparticles and Flow Rate Optimization

Solar thermal energy storage improves the practicality and efficiency of solar systems for space heating by addressing the intermittent nature of solar radiation, leading to enhanced energy utilization, cost reduction, and a more sustainable and environmentally friendly approach to meeting heating needs in residential, commercial, and industrial settings. In this study, an indoor experimental setup was employed to investigate the impact of a water-based Al2O3 nanofluid on the storage capacity of a flat plate solar collector under varying flow rates of the heat transfer fluid. The nanofluid, introduced at specific concentrations, was incorporated into a water-contained storage tank through which the hot heat transfer fluid circulated within a heat exchanger. This process resulted in the storage of thermal energy for future applications. The research identified that the optimal flow rate of the heat transfer fluid, corresponding to the maximum storage temperature, was 15 L per hour, and the ideal nanofluid concentration, associated with the maximum specific heat capacity of the storage medium, was 0.6%. Furthermore, the introduction of nanoparticles into the storage tank led to a significant increase in the specific heat of the water, reaching a maximum of 19% from 4.18 to 5.65 kJ/(kg·°C).

Flow rate analysis of high-pressure carbon dioxide through a combinational flow regulator

Flow control is essential in high-pressure CO2 systems. Flow regulators are widely used for flow adjustment in piping systems. In this paper, a novel combinational flow regulator is proposed, which contains four parallel branch channels, and each channel is arranged with a solenoid valve and an orifice plate. In order to analyze the internal flow characteristics of high-pressure CO2 and flow adjustment performance of the proposed flow regulator, a numerical model of the regulator is established, and the validation of numerical model is verified by experimental results. Then, the pressure and velocity characteristics are studied numerically. Finally, the flow adjustment performance is investigated numerically and experimentally from three aspects: variation of flow rate with differential pressure, variation of the product of flow coefficient and throttling area, and dynamic variations of pressure, temperature and flow rate of the flow regulator. This paper serves as a valuable reference for researchers utilizing flow regulators to adjust the flow rate of CO2 or other fluids.

Heat Transfer Analysis Methodology for Compression Hydrogen Storage Tank during Charge–Discharge Cycle

Heat transfer analysis for the compression hydrogen storage tank (CHST) during the charge–discharge cycle is necessary to ensure quick and safe refueling for fuel cell vehicles. In this paper, a dual‐zone dual‐temperature (DZDT) model for a CHST during the charge–discharge cycle process is established. The constant/variable mass flow rates and heat transfer coefficients (HTCs) are combined to form three methods. Method 1 uses constant mass flow rate and constant HTC. Method 2 uses variable mass flow rate and variable HTC calculated through the energy conservation equation. Method 3 uses variable mass flow rate and variable HTC calculated through the empirical equation. Then, these methods are applied to the DZDT model for heat transfer analysis in three cases. Research shows that for the charging process, the simulated hydrogen temperatures by Method 2 agree well with experiment data for three CHSTs. Method 1 has a maximum error of about 20°C for 19 L CHST, 15°C for 29 L CHST, and 25°C for 40 L CHST. The error of Method 3 is between Methods 1 and 2. The simulated hydrogen pressures by Methods 2 and 3 agree well with the experimental data, while Method 1 has a maximum error of about 5 MPa for 19 L CHST, 10 MPa for 29 L CHST, and 3 MPa for 40 L CHST. For the discharge process, the simulated hydrogen temperatures by Methods 2 and 3 have a relatively slight difference with the experimental data, while Method 1 has relatively significant differences for three CHSTs. Only slight differences exist between the simulated hydrogen pressures by Methods 1, 2, and 3 with the experimental data for three CHSTs. In short, Method 2 can simulate the hydrogen temperature and pressure well during the charge–discharge process. Method 3 can simulate the approximate hydrogen temperature and precise hydrogen pressure during the charge–discharge process. Method 1 can only simulate the hydrogen pressure during the discharging process. The conclusions of this article can inform researchers which analysis methods are more reasonable to choose in future hydrogen‐filling studies.