Total Airflow Research Articles

NGHIÊN CỨU CÁC THÔNG SỐ ĐẶC TRƯNG CỦA BUỒNG ĐỐT NGƯỢC DÒNG DẠNG ỐNG HÌNH KHUYÊN CỦA ĐỘNG CƠ TUA BIN KHÍ TÀU THỦY BẰNG PHƯƠNG PHÁP MÔ PHỎNG CFD

Thisarticle presents the numerical study of combustor aerodynamic parameters of marine gas turbine engines to evaluate the actual characteristics. With the 3D model built from the upstream tube-annular combustor of DR76 engine, using CFD approach to evaluate the flow structure, determine the total pressure drop, the airflow distribution into the linner in primary, secondary and dilution zones. As aresult, the cold pressure loss in the combustor was 5.5% of the inlet pressure, the air mass flow through the swirl zone by about 29%, the primary orifices and cooling channels by 40.5%, and the dilution zone by 30% of the total combustor airflow.

Water-based air purifier with ventilation fan system: a novel approach for cleaning indoor/outdoor transitional air during the pandemic

This article presents the design and fabrication of an air purifier that uses a water-based technique to clean indoor/outdoor transitional air to provide a low-tech air purifier against the annual smog crisis and the ongoing COVID-19 pandemic. The air purifier was designed and built. All tests were conducted in a closed room as well as a semi-outdoor area. Particle sizes of PM0.3, 0.5, 1.0, 3.0, 5.0, and 10 μm (particle/m3) were measured at an air inlet, air outlet, 2 m from an air inlet, and 4 m from an air outlet after 0, 5, 10, 15, and 20 min of air treatment, respectively, as well as CO2 levels and relative humidity (RH). The average airflow rate was also measured. When compare to 0 min, all parameters, except semi-outdoor PM0.3 and CO2 levels, tend to decrease in both indoor and semi-outdoor conditions. When measure by total airflow specification of a dual ventilation fan, the average airflow rate at an air outlet is reduced by 20 times.Article HighlightsDesign and fabrication of a water-based air purifier.A low-tech air purifier helping to protect against the annual smog crisis and the ongoing COVID-19 pandemic.The novel water-based air purifier effectively traps air particles ranging in size from 0.5 to 10 µm.

Role of Primary Freeboard on Staged Combustion of Hardwood Pellets in a Fixed Bed Combustor

In staged fixed bed biomass combustion, primary air is supplied beneath the fuel bed with secondary air then provided above in the freeboard region. For fixed bed configurations, the freeboard is further divided into a primary freeboard length (LI), which is upstream of the secondary air and a secondary freeboard length (LII), measured from the secondary air all the way to the exhaust port. Despite extensive research into fixed bed configurations, no work has been successfully completed that resolves the effects of changing LI on fuel conversion, both in the fuel bed and within the freeboard of batch-type biomass combustors. In this study, experiments on a 202 mm diameter and 1500 mm long batch-type combustor have been conducted to determine the effects of changing primary freeboard length over three secondary to total air ratios (Qs/Qt) and two total air flow rates (Qt). The impact of these conditions has been studied on (i) intra-bed fuel conversion, measured through burning rate (kg/m−2 s−1), fuel bed temperature (°C) and ignition front velocity (mm-s−1), as well as (ii) post-bed fuel conversion in the freeboard, expressed through freeboard temperatures and emissions (NOx ppm, CO2%, CO ppm, O2%). The fuel used throughout the above experiments was Australian hardwood pelletised biomass. Results show that changes to primary freeboard length over LI = 200 mm, 300 mm and 550 mm, or LI/D = 1.00, 1.48 and 2.72, respectively, affect both intra-bed and freeboard (post-bed) performance indicators. The highest values of burning rate, ignition front velocity and fuel bed temperature were observed for interim values of LI/D = 1.48 at Qs/Qt = 0.25 and Qt = 0.358 kg/m−2 s−1. Primary freeboard lengths of LI/D = 1.00 and 1.48 were found to have higher freeboard temperatures, NOx and CO2 as well as lower CO and O2 values as compared to LI/D = 2.72 at Qs/Qt = 0.50 and 0.75. Increasing Qs/Qt from 0.25 to 0.50 for LI/D = 1.00 and 1.48 initially increased freeboard temperatures, with an accompanying increase in NOx and CO2 as well as decrease in CO values. However, further increase in Qs/Qt to 0.75 lead to lower freeboard temperatures for all primary freeboard lengths.

A comparison between fossil and synthetic kerosene flames from the perspective of soot emissions in a swirl spray RQL burner

Swirl-stabilized turbulent spray flames operating at atmospheric pressure, with both a conventional Jet-A kerosene (‘A2’) and a synthetic fuel blend (‘C5’) and radially-injected dilution air were investigated from the perspective of soot emissions in a model Rich-Quench-Lean (RQL) combustor. The primary and downstream dilution air flow split was varied while keeping the global equivalence ratio constant (ϕg=0.4). 2.5 kHz PIV, 5 kHz OH-PLIF, and simultaneous 10 Hz Mie scattering and LII were used. Results revealed a correlation between OH and soot distributions. With no dilution air, soot volume fractions (fv) peaked in a v-shaped cone between the OH-containing regions along the spray cone and those anchored to the bluff body. With dilution air at 20% of total air flow, fv shifted to the central axis as OH distributions widened. At 40% dilution, soot initiation began farther downstream along the spray cone, OH regions merged into one, and fv peaked farther downstream at the edge of the Central Recirculation Zone (CRZ). With no air dilution, peak time-averaged fv was 20% lower in the C5 flame compared to A2, despite C5 having a higher aromatics content. However, at 20% dilution fv in C5 increased by 75% compared to the no dilution case. fv in the C5 flame dropped by 12.5% in the high dilution case compared to 40% reductions in A2. Mie scattering showed that the C5 spray was shorter and more resistant to change from dilution air compared to A2. The different spray behaviours were due to C5’s flat boiling range, lower viscosity and density, leading to higher evaporation rates. Detailed chemistry laminar flamelet simulations of A2 and C5 showed that peak soot precursor species mass fraction values and temperatures decreased as the scalar dissipation increased and a significantly stronger presence of toluene in the C5 flame compared to A2. Toluene’s soot yielding behaviour may cause C5’s increased fv with moderate dilution compared to A2. C5 demonstrates the importance of the fuel’s chemical and physical properties when developing future sustainable aviation fuels for practical applications to maximize their soot mitigation potential.

Numerical simulation of the effect of air-intake on the indoor flow field of a dedusting equipment cabin used in tunnel construction

There is a significant amount of dust during tunnel construction. As a comprehensive prevention method for tunnel dust, dust collector technology has been widely used in tunnel construction. The flow field distribution in a dedusting equipment cabin directly affects the treatment efficiency of tunnel dust. In this study, using a dedusting equipment compartment with 5 (in row) × 20 (in column) filter cartridges (FCs, diameter of 0.35 m) as the research object, the effects of air-intake mode, position, and other parameters on the airflow rate of FCs inside the cabin, and indoor air distribution characteristics were studied using a numerical calculation method, which was verified by an experiment. The results indicated that for the cabin with only an end air-intake, the length of the cabin cannot be too long, as this would cause a low airflow rate of the FCs located at the center of the cabin. Furthermore, the effects of setting a baffle and grille on the total airflow rate of the FCs inside the cabin with only an end air-intake was more significant than that with both an end air-intake and side air-intakes, the difference of the total airflow rate among them can be up to 59%. Setting a baffle at the end of an air-intake significantly reduced the total airflow rate of the FCs about 59%, which was significantly increased about 5% by setting grilles. Additionally, the side air-intakes improved the total airflow rate of the FCs more than the end air-intake by about 24%, but the intake efficiency of the former was lower than that of latter by about 61%. Finally, based on cabins with only an end air-intake, setting the side air-intakes on the cabin where the airflow rate of FCs is low, can significantly improve the total airflow rate of FCs in the cabin, particularly the FCs around the side air-intakes, the increase here can reach 36% compared with other locations.

Correlations between objective and subjective tests of nasal patency in patients undergoing septoplasty.

This study assessed correlations between pre- and post-operative objective and subjective nasal patency test results in patients undergoing septoplasty to treat nasal septum deviation. Eighty nasal septum deviation patients who underwent septoplasty were prospectively enrolled. Nasal Obstruction Symptom Evaluation questionnaire scores, anterior rhinomanometry and acoustic rhinometry data were compared pre-operatively and three months after surgery. The left, right and total volume and left, right and total minimum cross-sectional area acoustic rhinometry values were compared. The left volume, total volume, left minimum cross-sectional area and total minimum cross-sectional area differed significantly between the two time-points (all p < 0.05). The total resistance, inspiratory total airflow, expiratory total resistance and expiratory total airflow rhinomanometric data did not differ between the two timepoints (all p > 0.05). This study suggested that subjective tests such as the Nasal Obstruction Symptom Evaluation questionnaire are optimal to identify complaints and assess post-operative satisfaction.

Identification of air leakage in a household heat pump tumble dryer

Leakage of air in tumble dryers is an important parameter regarding the energy efficiency of the drying process. In general, tumble dryers are prone to leakage, therefore further investigation and optimization in this field is of great interest. This study investigates and quantifies leakage of air within the closed-loop system of an in-situ household heat pump tumble dryer. Each potential leakage location was characterized by leakage curve obtained either by isolated or cumulative measurements using system pressurization method. Based on the static pressure distribution within the closed-loop system, the leakage outflow and inflow were quantified. The leakage of air at the rear and front drum seal was evaluated with and without drum movement. The results indicated the highest leakage outflow rate at the heat pump housing, which represents 12,6% of the total drying air flow rate within the closed-loop system. Sealing heat pump housing improved the condensation efficiency from B to A class according to the IEC 61121.

Experimental Investigation of Air Bubble Curtain Effects on Water Wave Field

This paper studies the effects of an air bubble curtain on surface water waves. Water particle velocities and free surface elevations were measured simultaneously at two cross-shore locations downstream of the air bubble curtain. Measurements were carried out for regular waves using different air bubble curtain configurations. Free surface elevations were measured using resistive gauges and the instantaneous velocities were acquired using an Acoustic Doppler Velocimeter (ADV). The characteristics of the free surface elevation time series, velocity field and turbulence are analyzed and discussed. The free surface elevation was found to be attenuated by the air bubble curtains. The phase averaged velocity profiles also depict the effect of the air bubbles in the flow field by generating milder longitudinal velocities (u) and by increasing the transverse component of the velocity (w). The increase in the turbulence intensity and the different energy spectrum produced by the air bubble curtain is also observed. The experimental results indicate that the thickness of the air bubble curtain and the total air flow rate affects the wave field.

Heat recovery in ventilation systems in different climates: energy and economic comparison in old and new schools in COVID-19 pandemic conditions

Ensuring adequate ventilation and increasing total airflow supply to occupied spaces is one of the recommendations of the World Health Organization to contain the airborne diffusion of COVID-19 virus in schools. In this article, different technical solutions are compared combining thermal recovery by a sensible or a total heat exchanger and thermodynamic recovery by a heat pump (HP). An energy analysis is carried out in two different climates and for different values of the ventilation load to the heating + cooling load ratio, to evaluate the relative advantages of the systems in old schools (mostly diffused and poorly thermal insulated) and new ones (highly thermal insulated). Results indicate that the combined HP – total heat recovery system is the most efficient solution both in colder and milder climates, giving a nonrenewable primary energy (PE) ratio of 3.9 and 3.0, respectively. PE saving compared to PE consumption varies between 6 and 20% for the different systems in old poorly thermal insulated schools, increasing remarkably in new high energy performance buildings. An economic analysis reveals that the preferable solution is the HP only. A sensitivity analysis allows to evaluate how energy and economic results vary with the parameters considered.

Precision Ventilation in an Open-Plan Office: A New Application of Active Chilled Beam (ACB) with a JetCone Feature

Mixing ventilation systems effectively improves thermal comfort in open-spaces due to adequate turbulent mixing of the cold stream with ambient air. This study introduces the concept of precision ventilation for achieving local thermal comfort in a mixing ventilation system. This precision ventilation system provides asymmetrical airflows from an active chilled beam (ACB) to each of the office occupants. These ACBs provide air velocities with different magnitudes and directions. To achieve different magnitudes and directions, JetCones are used to vary the airflow in different parts of the ACB. The performance of the precision ventilation system was analyzed using full-scale laboratory experiments and computational fluid dynamic (CFD) simulations. The full-scale laboratory experiments were conducted in a 4.2 m × 3 m × 2.8 m (L × W × H) thermal isolated room with an open-plan dual desk-chair setup. The jet-cones in the ACB unit were adjusted to throw the required amount of flow to the occupants. The occupants had different metabolic rates of 1.2, 1.4, and 1.6 in a warm office space. The room set point temperatures varied between 23 and 26 °C. The experimental and CFD results show that occupants facing symmetrical airflow distribution and with a constant 1.2 metabolic rate had a similar PMV index. The occupants with 1.2, 1.4, and 1.6 metabolic rate were exposed to asymmetrical airflows, i.e., 30%, 58%, and 70% of the total airflow. Occupants with higher metabolic rates were kept thermally neutral, in the −0.5 to +0.5 PMV range, by increasing the air velocity and room temperature to 0.4 m/s and 25 °C, respectively.

Effects of cross airflow and burner distance on temperature profile and flame morphology of dual tandem pool fires

Understanding multiple fire sources interactions in cross airflow that frequently occur in wildland fire or industrial process accident scenario is helpful for establishing guidelines for fire protection engineering. This paper experimentally studies the thermal characteristic and flame behavior of dual tandem pool fires with equal- and unequal- heat release rates in varying separation distances (S) under cross airflow (u). Two square diffusion burners were used employing propane as fuel with varied heat release rates (HRR) at six separation distances, with a total of 216 experimental conditions were considered comprehensively. Flame merging condition, IR-measured flame temperature profile, flame height and flame horizontal projection length were quantified and analyzed. Results show that the flames tend to merge more easily in cross airflow when the HRR of the upstream flame is larger. The maximum temperature in the flame region increases with the increasing cross airflow velocity for both merging and non-merging flames, and the downstream pool fire's maximum temperature is lower than that of the upstream pool fire in the cases of non-merging. For merging cases, flame horizontal projection length decreases as S/D increases, while flame height changes little for varying S. For non-merging cases, flame height of downstream pool fire has an increasing trend with the increasing separation distance, while flame horizontal projection length declines in reverse due to the flame blockage effect. Three combustion states of dual fires are identified according to their force interactions: State I-pressure thrust dominated, State II-pressure thrust competes with cross airflow inertial force, State III-cross airflow inertial force dominated. Finally, a scaling analysis is performed to characterize the flame height and horizontal flame projection length based upon the competition mechanisms between total buoyant flow flux and cross airflow momentum flux for merging flame and non-merging flame in state III. This study provides experimental data and a scaling analysis into the fundamental physics of equal and unequal multiple pool fires interactions under cross airflow.

Synergetic Synthesis of Nonlinear Laws of Throttle Control of a Pneumatic Drive

Currently, a significant trend in control in robotic systems is developing and improving linear and nonlinear control algorithms to improve the overall quality of production with high accuracy and adaptability. The present study considers a synergistic synthesis of throttle control of a pneumatic distributor valve and backpressure control for piston rod positioning. The article presents the synthesis of control laws for the position of a pneumatic cylinder piston using the method of analytical design of aggregated regulators (ADAR) of synergetic control theory (STC), which allows operation with nonlinear mathematical models, eliminating the loss of information about the object during linearization. A comparative calculation of the energy efficiency of backpressure control and throttle control methods was carried out, while the numerical value of the total airflow with throttle control is 0.0569 m3⁄s and, with backpressure control, it is 0.0337 m3⁄s. Using a P controller in a linear model gives a transient oscillatory process damped in 2–2.5 s. When using a PID controller, the process has an overshoot equal to 11.5%, while the synergistic controller allows you to smoothly move the drive stem to a given position without overshoot. The parametric uncertainty analysis of the considered mathematical model is carried out. The model’s main parameters are identified, which change the actual functioning of the system under study. The inconsistency of applying classical control laws based on typical controllers to parametrically indeterminate mathematical models is shown.

Experimental study on the net outdoor airflow ratio in supply air of membrane-based energy recovery ventilator

The total energy recovery ventilator for outdoor air handing plays an important role in reducing energy consumption of the ventilation system. At the same time, the cross infection between fresh air and return air is a direct threat to the safety of energy recovery components with the influence of COVID-19. Therefore, how to improve the total exchange effectiveness and net outdoor air flow ratio in supply air of the heat recovery system has become an urgent problem to be solved. In this study, the composite membrane was prepared by non-woven fabric, siloxaneamide and lithium chloride solution, which was used as the membrane for the heat and mass transfer between fresh air and return air. The variation of the selective permeability of the composite membrane was studied experimentally. The experimental results show that the highest permeance of the composite membrane for the water vapor permeability can reach until 32.5×10-8kg/m2·s·Pa. The net outdoor air flow ratio in supply air is 94% when the air volume is 550m3/h The heat exchange efficiency of the heat recovery device is 63.2% under the conditions of the dry and wet bulb temperatures of return air and outdoor air are 21.2°C/12.9°C and 2.3°C/1.2°C, respectively.

Medidas da aeração nasal e fluxo máximo inspiratório em crianças com respiração oral pré e pós manobras de limpeza e massagem nasal

ABSTRACT This study aimed at investigating the effects of nasal cleansing and massage maneuvers on upper airway patency in mouth-breathing children. This is a case report on eight children, aged 7 to 10 years, with a speech-language-hearing diagnosis of mouth breathing and otorhinolaryngological assessment and clinical diagnosis of rhinitis. Nasal airflow and patency were respectively assessed with the Glatzel mirror and Peak Nasal Inspiratory Flow (PNIF). Then, they were submitted to nasal cleansing and massage maneuvers with a saline solution, followed by reassessment with the Glatzel mirror and PNIF to compare results. The medians of total nasal airflow quantification were significant. Data on unilateral nasal cavity measurement indicated a sharp increase in nasal airflow in each nostril, with statistically significant differences between before and after nasal cleansing and massage maneuvers. The medians of the total PNIF were significant after the cleansing. It is concluded that the nasal airflow increased in PNIF after the cleansing maneuver.

Nasal airflow comparison in neonates, infant and adult nasal cavities using computational fluid dynamics

Background and objectiveNeonates are preferential nasal breathers up to 3 months of age. The nasal anatomy in neonates and infants is at developing stages whereas the adult nasal cavities are fully grown which implies that the study of airflow dynamics in the neonates and infants are significant. In the present study, the nasal airways of the neonate, infant and adult are anatomically compared and their airflow patterns are investigated. MethodsComputational Fluid Dynamics (CFD) approach is used to simulate the airflow in a neonate, an infant and an adult in sedentary breathing conditions. The healthy CT scans are segmented using MIMICS 21.0 (Materialise, Ann arbor, MI). The patient-specific 3D airway models are analyzed for low Reynolds number flow using ANSYS FLUENT 2020 R2. The applicability of the Grid Convergence Index (GCI) for polyhedral mesh adopted in this work is also verified. ResultsThis study shows that the inferior meatus of neonates accounted for only 15% of the total airflow. This was in contrast to the infants and adults who experienced 49 and 31% of airflow at the inferior meatus region. Superior meatus experienced 25% of total flow which is more than normal for the neonate. The highest velocity of 1.8, 2.6 and 3.7 m/s was observed at the nasal valve region for neonates, infants and adults, respectively. The anterior portion of the nasal cavity experienced maximum wall shear stress with average values of 0.48, 0.25 and 0.58 Pa for the neonates, infants and adults. ConclusionsThe neonates have an underdeveloped nasal cavity which significantly affects their airway distribution. The absence of inferior meatus in the neonates has limited the flow through the inferior regions and resulted in uneven flow distribution.

Respiratory infection risk-based ventilation design method

A new design method is proposed to calculate outdoor air ventilation rates to control respiratory infection risk in indoor spaces. We propose to use this method in future ventilation standards to complement existing ventilation criteria based on the perceived air quality and pollutant removal. The proposed method makes it possible to calculate the required ventilation rate at a given probability of infection and quanta emission rate. Present work used quanta emission rates for SARS-CoV-2 and consequently the method can be applied for other respiratory viruses with available quanta data. The method was applied to case studies representing typical rooms in public buildings. To reduce the probability of infection, the total airflow rate per infectious person revealed to be the most important parameter to reduce the infection risk. Category I ventilation rate prescribed in the EN 16798-1 standard satisfied many but not all type of spaces examined. The required ventilation rates started from about 80 L/s per room. Large variations between the results for the selected case studies made it impossible to provide a simple rule for estimating the required ventilation rates. Consequently, we conclude that to design rooms with a low infection risk the newly developed ventilation design method must be used.

Parametric analysis of an air-based radiative cooling system coupled to a thermal storage wall for a low-income household

Research on natural cooling of buildings has produced an extensive scientific bibliography since 1980s. Nevertheless, few examples of complete experimental systems are registered, and rigorous procedures for their dimensioning are currently not available. This work analyses the performance of an air-based low energy radiative cooling system in Chile. The system is composed of a series of specialized radiative air collectors, a mechanical ventilation system, and a thermal storage wall, which is part of the indoor environment. The design has been tested in an experimental prototype where external and internal environmental conditions have been monitored during a full week in midsummer conditions. The data obtained is used to validate an analytical model designed to study the behavior of each component and the system’s performance. This work studies the relationship between the radiator surface, the air volume flow rate, and the thermal storage wall volume that serves to neutralize the thermal loads, maintaining comfortable temperature conditions throughout the day. Comparison of the simulations with and without thermal conditioning has been conducted. In term of the system sizing, a thermal wall of 2.55 m3 and a total air flow rate of 48 m3/h is required to reach the optimal operating point of the first floor of the house. A sensibility analysis indicated that increasing the number of collectors slightly reduces the wall’s size. Based on these conditions, the work concludes with the proposal of a simple procedure for the sizing of passive cooling systems installed in social housing developments.

CFD Simulation of an Internally Cooled Biomass Fixed-Bed Combustion Plant

The reduction of bed temperature in fixed-bed biomass combustion is an effective measure to lower pollutant emissions. Air staging and bed cooling solutions are active strategies to decrease the fuel bed temperature. This work presents a CFD study of a biomass fixed-bed combustion plant that is equipped with an internal cooling bed system. Eight different cases are calculated to analyze the effect of the total airflow, air staging ratios and bed cooling system on biomass combustion. The findings are validated against experimental data from the literature. The results show good accordance between the numerical results and the experimental data. The primary airflow rate has the biggest influence on the bed’s maximum temperatures. The internal bed cooling system is able to achieve an average bed temperature reduction of 21%, slowing the biomass thermal conversion processes. Bed cooling techniques can be combined with air staging and primary airflow reduction to reduce bed temperatures in order to reduce pollutant emissions and other undesirable phenomena, such as fouling or slagging.

Numerical Investigation of Latent Thermal Storage in a Compact Heat Exchanger Using Mini-Channels

This paper aims to numerically investigate the thermal enhancement of a latent thermal energy storage component with mini-channels as air passages. The investigated channels in two sizes of internal air passages (channel-1 with dh = 1.6 mm and channel-2 with dh = 2.3 mm) are oriented vertically in a cuboid of 0.15 × 0.15 × 0.1 m3 with RT22 as the PCM located in the shell. The phase change is simulated with a fixed inlet temperature of air, using ANSYS Fluent 19.5, with a varying number of channels and a ranging air flow rate entering the component. The results show that the phase change power of the LTES improves with by increasing the number of channels at the cost of a decrease in the storage capacity. Given a constant air flow rate, the increase in the heat transfer surface area of the increased number of channels dominates the heat transfer coefficient, thus increasing the mean heat transfer rate (UA). A comparison of the channels shows that the thermal performance depends largely on the area to volume ratio of the channels. The channel type two (channel-2) with a slightly higher area to volume ratio has a slightly higher charging/discharging power, as compared to channel type one (channel-1), at a similar PCM packing factor. Adding fins to channel-2, doubling the surface area, improves the mean UA values by 15–31% for the studied cases. The variation in the total air flow rate from 7 to 24 L/s is found to have a considerable influence, reducing the melting time by 41–53% and increasing the mean UA values within melting by 19–52% for a packing factor range of 77.4–86.8%. With the increase in the air flow rate, channel type two is found to have considerably lower pressure drops than channel type one, which can be attributed to its higher internal hydraulic diameter, making it superior in terms of achieving a relatively similar charging/discharging power in exchange for significantly lower fan power. Such designs can further be optimized in terms of pressure drop in future work, which should also include an experimental evaluation.

Numerical and Experimental analysis of the air distribution system in a data center building to improve the thermal performance

The purpose of the management of air distribution systems is to solve the problems in the cooling of data centers through minimizing the hot air recirculation and cold air bypass. In this paper, experimental and numerical analyses are conducted for the AUT data center. The data center performance indices have been compared between experimental and numerical solutions. According to temperature contours at a height of 1 m from the raised floor, recirculation of hot air to the cold aisle enclosure has occurred. For enhancement, the thermal management of the data center, cold aisle enclosure with decreasing supply airflow temperature to 18 , and hot aisle enclosure with return hot air from plenum ceiling to CRAC units were investigated. With the decrease in the total airflow supplied by CRAC units in the cold aisle enclosure and hot aisle enclosure models, the problem of Super-micro servers that experience about 50% more airflow than defined airflow for them in the base model, has been solved. The load on the cooling systems decreased from 13.2 kW up to 7.8 kW in hot aisle containment, the result is a hot aisle is a more suitable and appropriate configuration for the data center