ANSYS Fluent CFD Research Articles

CFD Simulation of Aerodynamics Truck Using Cylinder as Drag Reduction Device

Reducing drag is an excellent approach to improving truck efficiency and saving fuel. The addition of the cylinder could be an alternative for drag reduction devices like the windshield that has a similar function to enhance the truck’s aerodynamic performance. A numerical analysis was performed using Ansys Fluent CFD software to estimate the influence of the cylinder on the truck's drag force. The study was conducted by comparing truck without additional cylinder above the truck’s head, truck with windshield, and truck with cylinder variations, which round, type-I, and type-D cylinders. In the simulation, the analysis was carried out at a velocity of 30 m/s using the k-epsilon turbulence model. A grid independence test was conducted to minimize errors and optimize iteration time. The simulation results showed that using round, I-type, and D-type cylinders as an alternative to the windshield reduced the truck's drag coefficient, with the D-type cylinder achieving the highest reduction in drag coefficient, which is 0.72. Modifications in the design of the drag reduction cylinder can lower fuel consumption indirectly by 6.95 % using a D-type cylinder.

Studi Numerik Pengaruh Penggunan Splitter Plate Terhadap Sifat Aliran di Sekitar Penampang Persegi

The phenomenon of the movement of fluid flow across an object plays an important role in terms of transportation. Different body shapes will produce different fluid flow characteristics and greatly affect the function of the body shape, so it is important to know the characteristics of fluid flow, so that the factors causing losses in a construction that are not in accordance with the natural properties of the fluid can be identified. If the drag is large can be reduced, the energy needed to move can be reduced and save fuel. the use of numerical methods is a way of studying flow characteristics that is relatively inexpensive with a scientifically justifiable level of accuracy. The problem of this study is how the characteristics of the fluid flow to the forces that pass through the square cross section. This study uses a square geometry test model and a single splitter plate geometry test. The research was carried out by computational methods using Ansys FLUENT CFD software with the Realizable k-ε turbulence model. The results showed that the use of a splitter plate resulted in a decrease in Cd, -CPb values and an increase in speed (u). This indicated that the use of a splitter plate could reduce resistance and pressure and expedite the distribution of fluid flow. and there is an increase in the Cl value parameter, this is due to the enlargement of the wake. From this study it was found that the use of a splitter plate was good in reducing Cd values, this is in accordance with the literature
 Kata kunci: Ansys fluent, CFD, fluid, Reynolds, drag coefficient, pressure coefficient, lift coefficient

Effect of thermal manikin shape on thermal comfort parameters prediction uncertainties: a numerical study

The main goal of the study is to evaluate the effect of the thermal manikin shape on the uncertainty of thermal comfort parameters CFD prediction. Numerical simulation of the airflow and heat transfer was carried out in a model room with displacement ventilation where a standing heated thermal manikin is located (test by P.V. Nielsen et al.). Numerical modelling was carried out using three manikin shapes: the detailed one (close to the human body shape), the simplified (block) one, and the single-parallelepiped shape. The 3D calculations were carried out using the ANSYS Fluent CFD package. Turbulence modelling was performed using the Reynolds-Averaged Navier-Stokes (RANS) approach with the standard k-ε turbulence model. The uncertainties in the CFD-predicted draught rating (DR), percentage dissatisfied caused by vertical air temperature difference (PD), the predicted mean vote (PMV) and the predicted percentage dissatisfied (PPD), are discussed. The main result of the paper is the quantitative evaluation of the changes in the local velocity, temperature and thermal comfort parameters due to the thermal manikin shape simplification. It was found that the shape simplifications are suitable if the goal of the study is to predict the integral parameters.

Hydraulic modelling of a catalytic converter for pollutant reduction in atmosphere

Air pollution caused by cars is a major contributor to the greenhouse effect, making it an issue of widespread concern. End-of-combustion of an engine produces pollutants such carbon monoxide (CO), oxides of nitrogen (NOx), oxides of sulphur (SOx), particulate particles and unburned hydrocarbons (HC). The environment, air quality, and human health are all negatively affected by these contaminants. A catalytic converter is a pollution control device for every fuel-operated automobile exhaust system. Increasingly low emission standards and automobile space constraints necessitate optimizing the device geometry. The uniformity index parameter mainly judges a catalytic converter’s smooth working and operational life. In the present study, 16 catalytic converter geometry designs are investigated. Their effects on exhaust flow distribution, i.e., uniformity index, pressure drop, and peak pressure at monolith substrate entry, are identified and visualized through contour plots. A finite volume approach is used to study hydraulic diffusion inside the device with the help of the ANSYS Fluent CFD package. Two-dimensional axisymmetric CFD simulations identify optimum design parameters among the considered geometries. The design of diffuser geometry is crucial in maintaining a uniform flow across monolith honeycomb structures.

Thermal and hydrodynamic analysis of a self-purging hot reservoir variable conductance heat pipe

A new design of a hot reservoir variable conductance heat pipe (VCHP) is proposed and investigated in this study. While a hot reservoir VCHP can provide much tighter thermal control performance in comparison to a traditional cold reservoir VCHP, it was seen that the hot reservoir design is prone to more common operating failures due to the accumulation of the working fluid inside the reservoir. Once accumulated, this excessive working fluid in the reservoir can only be removed by diffusion which takes a long time. In this study, we propose and investigate a new design for the hot reservoir VCHP that would perform an additional function of working fluid vapor purging in addition to operating as a normal heat pipe. In the proposed design, the non-condensable gas (NCG) section of the heat pipe is connected to the reservoir by an external tube, forming a NCG flow-inducing loop configuration, hence the name self-purging hot reservoir VCHP (SPHR-VCHP). With proper placement of the NCG pipe in the VCHP a pressure-induced flow is generated through the loop from the NCG section towards the reservoir. It is shown that this loop flow can remove the excess working fluid vapor in the reservoir significantly faster than by diffusion. A Fortran code to simulate the two-phase flow in the heat pipe section combined with an ANSYS Fluent CFD model of the external loop is employed to predict the fluid flow, heat transfer, and mass transfer behaviors inside the SPHR-VCHP. An experiment is set up for the SPHR-VCHP that is made of a 291 mm long titanium tube with an inner diameter of 14.7 mm. The working fluid and the NCG are acetone and helium, respectively. The CFD predictions of wall temperature are validated by the experimental data with mean absolute error equal to 2.68%. A thorough CFD study is then performed to optimize the loop design in order to enhance purging rates by changing the size of the NCG tube to operate under microgravity conditions for space applications. Based on this study an optimum NCG pipe diameter equal to 40% of the inner diameter and pipe length equal to the length of the evaporator section is suggested. The wall temperature results show that the SPHR-VCHP design does not impact the thermal performance of the original hot reservoir heat pipe, while also having a self-purging capability that makes the design safe from working fluid accumulations issues.

Numerical Study of Turbulent Swirling Diffusion Flame Under Lean and Rich Conditions Using Turbulence Realizable k-epsilon Model

ABSTRACT This work investigates numerically a non-premixed swirling flame in a coaxial burner with a radial fuel injection under lean and rich conditions of mixtures. The swirler is placed in the annular part of the burner. The fuel is injected radially through eight holes symmetrically distributed on the periphery of the central tube. All simulations are carried out using the ANSYS-Fluent CFD code. The turbulence is captured using the Reynolds Averaged Navier-Stokes approach. Chemistry/turbulence interaction is resolved using the Eddy Dissipation Model. Simulations are performed with a global equivalence ratio ranging from 0.5 to 1.3. Model validation is achieved by comparing computed results to our experimental data of Stereoscopic Particle Image Velocimetry obtained in the case of the stoichiometric regime. Good agreement between numerical results and experimental measurements is assigned. The central recirculation zone and the swirling jet region due to the presence of the swirl are well predicted by the simulations. The effect of the global equivalence ratio on the profile of axial velocity, temperature distributions and pollutant emissions (CO and NOx) is numerically studied. From dynamic point of view, the equivalence ratio modifies the mean axial velocity of the swirling diffusion flame. The increase of equivalence ratio destabilizes the flame by increasing the liftoff height. NO production decreases by the increasing of the equivalence ratio.

Vortex-induced vibration of two tandem square cylinders with different restraint conditions

The present work investigates the vortex-induced vibration of twin square cylinders at Re = 150 with three restraint conditions. (Ⅰ) the upstream cylinder (UC) is free to oscillate while the downstream cylinder (DC) is fixed; (Ⅱ) both cylinders are free to oscillate, and (Ⅲ) the UC is fixed while the DC is free to oscillate. The centre-to-centre distance between the cylinders is fixed as 4.0B, and the mass ratio of the cylinder is m* = 3. The computations are performed for the reduced velocity ranging from 1 to 15 under each restraint condition. The flow dynamics are described by the two-dimensional incompressible Navier-Stokes equations and solved numerically using the Ansys Fluent CFD code (based on the finite volume method and SIMPLEC algorithm. It is found that whether the DC oscillates, the UC will exhibit the soft-lock-in phenomenon within the co-shedding regime. At high reduced velocities, the UC re-shows the soft-lock-in phenomenon when the DC is fixed. Whether the UC oscillates, the DC will exhibit the soft-lock-in phenomenon within the reattachment regime. For Case-Ⅱ, the strong vortex falling off the leeward side of the UC leads to a sharp decrease in distance between the two cylinders, and the DC exhibits the soft-lock-in phenomenon again.

Fire smoke dispersion inside and outside of a warehouse building in moderate and strong wind conditions

A moderate-sized (8 MW) fire was modelled in a warehouse located in an urban area with diverse architecture, in wind conditions. The investigation includes the effects of neighbouring architecture on the wind field, and in consequence on the smoke control performance and the smoke dispersion in the near-field of the building. Overall, 25 CFD simulations were performed with ANSYS Fluent CFD code, for wind velocities of 5 m/s (moderate), 10 m/s (strong) at 12 wind angles each (0°–330°, 30° increment), and at 0 m/s for reference. The building smoke venting system's performance was affected by the wind, reaching 74%–114% and 78%–158% of the reference mass flow at the moderate and strong wind velocities, respectively. Surprisingly, in multiple cases the exhaust flow rate of ventilators was increased, rather than hindered by the wind. We attribute this to the arrangement of inlets and outlets on façades and the resulting pressure difference between the wall and roof openings. The smoke plume was highly dependent on the wind angle, and the type of architecture up- and downwind of the fire. Significant urban canyon effects and large vortices forming behind tall buildings were observed, leading to smoke accumulation in a large distance from the fire.

Analysis of magneto-natural-convection flow in a semi-annulus enclosure filled with a micropolar-nanofluid; a computational framework using CVFEM and FVM

Micropolar fluids are the media in which their behavior is affected by the microrotation of the substructure particles. In the present work, the natural-convection flow of a micropolar-nanofluid (Al2O3/water) in the presence of an inclined magnetic field in a semi-annulus enclosure is investigated. The influence of active parameters on magneto-natural convection is investigated. The governing equations (mass, momentum, microrotation, and energy) are numerically solved by CVFEM. Moreover, for some conservative comparisons, the equations are solved by Ansys Fluent CFD code which is conjugated by an innovative nondimensionlization scheme. The effects of important parameters are investigated on the streamlines, isotherms, microrotation contours, the maximum absolute value of stream function (Ψmax), the average Nusselt number (Nuave) and the maximum absolute value of microrotation Nmax∗. The results discovered that the values of Nuave descend with ascending the Hartmann number (Ha) and material parameter (K) while it ascends with ascending Rayleigh number (Ra) and particle volume fraction (ϕ). The value of Nuave descends 10.8% while Nmax∗ increases 19.8% when K increases from 1 to 2. The value of Nuave descends 44.83% when Ha increases from 25 to 75 at λ=45°. The minimum value of Nuave occurs at λ=45° for Ha=25 and at λ=30° for Ha=50 and Ha=75.

Comparative Analysis of Battery Thermal Management System Using Biodiesel Fuels

Liquid fuel has been the main source of energy in internal combustion engines (ICE) for decades. However, lithium-ion batteries (LIB) have replaced ICE for environmentally friendly vehicles and reducing fossil fuel dependence. This paper focuses on the comparative analysis of battery thermal management system (BTMS) to maintain a working temperature in the range 15–35 °C and prevent thermal runaway and high temperature gradient, consequently increasing LIB lifecycle and performance. The proposed approach is to use biodiesel as the engine feed and coolant. A 3S2P LIB module is simulated using Ansys-Fluent CFD software tool. Four selective dielectric biodiesels are used as coolants, namely palm, karanja, jatropha, and mahua oils. In comparison to the conventional coolants in BTMS, mainly air and 3M Novec, biodiesel fuels have been proven as coolants to maintain LIB temperature within the optimum working range. For instance, the use of palm biodiesel can lightweight the BTMS by 43%, compared with 3M Novec, and likewise maintain BTMS performance.

The impacts of surface roughness on Indoor aerodynamics of virus-laden particles: The case of contact, deposition, and resuspension

The increasing prevalence and high morbidity of the SARS-CoV-2 virus during the COVID-19 pandemic drew widespread global attention. Surface contact is among the most common ways for the infection to spread within people, especially in buildings and the built environment. The roughness characteristics of finishing materials used in buildings vary, affecting the surface's ability to deposit and resuspend any particles that come into contact with these interfaces. Resuspension of particles indoors may increase the risk of consequent exposure through inhalation. However, little is known about surface roughness characteristics' role in airborne transmission of virus-laden particles in building indoor environments. The study examines the impact of surface roughness characteristics on the airborne transmission of the SARS-CoV-2 virus, considering indoor aerodynamic forces and their influence on particle contact with surfaces, deposition, and resuspension. The study applies Ansys Fluent CFD simulation tools to investigate the effect of volumetric flow rates and air velocity on concentration, deposition, and resuspension. The study also employs an empirical model to estimate surface roughness characteristics' impacts on particle resuspension rate. The results indicate that particle concentration and deposition rates indoors increase with increasing volumetric airflow rates. The particle resuspension rates also decreased with the increasing surface roughness of indoor surface materials. The highest resuspension rate recorded was 3.3 x 10-6, and the lowest was 1.6 x 10-6 s-1. Therefore, the outcome provides information on the implications of surface material selection and its effects on indoor air quality, health, and virus transmission. The study will offer valuable information for building engineering and design professionals in combating airborne disease transmission due to indoor surface characteristics.

Numerical Analysis of Heating Technique in Corium Melt Pool Convection Flow Field & Thermal Interaction in a Volumetrically Heated Molten Pool

In-Vessel Retention (IVR) is one of the existing strategies of severe accident management of LWR, which intends to stabilize and isolate corium & fission products inside the reactor pressure vessel (RPV) and primary containment structure. Since it has become an important safety objective for nuclear reactors, it is therefore needed to model and evaluate relevant phenomena of IVR strategy in assessing safety of nuclear power reactors. One of the relevant phenomena during accident progression in the oxidic pool is non-uniform high heat generation occurring at large scale. Consequently, direct experimental studies at these scales are not possible. The role computer codes and models are therefore important in order to transpose experimental results to reactor safety applications. In this paper, the state-of-the-art ANSYS FLUENT CFD code is used to simulate Non-uniform heat generation in the lower plenum by the application of Cartridge heating under severe accident conditions to derive the basic accident scenario. However, very few studies have been performed to simulate non-uniform decay heat generation by Cartridge heaters in a pool corresponding lower plenum of power reactor. The current investigation focuses on non-uniform heating in the fluid domain by Cartridge heaters, which has been done using ANSYS FLUENT CFD code by K-epsilon model. The computed results are based on qualitative assessment in the form of temperature and velocity contour and quantitative assessment in terms of temperature and heat flux distribution to assess the impact of heating method on natural convective fluid flow and heat transfer.

Combat aircraft as airborne launch platforms for space rockets

PurposeThe purpose of this study was to analyze the possibility of using combat aircraft including decommissioned as a platform for launching and carrying space rockets with satellites (nano and microsatellites). Thus, an airborne-launcher-to-space-system may be attractive to countries without ground-based space rocket launch sites.Design/methodology/approachFor considered launch-to-orbit system configurations, simulations of space rocket effects on aerodynamic characteristics were performed using computational fluid dynamics (CFD ANSYS Fluent) methods. In addition, experimental studies were performed in a wind tunnel to verify the numerical simulations. Discrete models of the aircraft structure were developed for analysis using finite element method (FEM). The analysis of simulated structural properties of the models was carried out to test its stiffness and mass characteristics important for solving the static and dynamic problems of the structure. The validation analyses of aircraft models were based on mass distribution estimation and matching the stiffness properties of the individual airframe structural assemblies.FindingsThe results of numerical analyses and tunnel tests indicate that the influence of carrier rockets on the change of aerodynamic and strength characteristics of the airframe is rather negligible. The aircraft can be used as launching platforms for space rockets. Simulations have indicated that the aircraft will successfully perform a mission of taking away and launching a rocket of at least about 1,000 kg total weight with a 10 kg space payload included.Practical implicationsThe combat aircraft can be used as launch platforms for space rockets, and the air/rocket set can become the equivalent of responsive space assets for countries with small space budgets.Originality/valueThe work presents original results obtained by the authors during a preliminary design of a low-cost satellite launch system consisting of a carrier aircraft and a space rocket orbiter. The possibility of using decommissioned combat aircraft as air-launch-to-orbit platforms was taken into consideration. In the absence of aircraft design documentation, reverse engineering methods and techniques were used to develop aircraft geometry and airframe strength structure. Use of CFD, FEM and simulation methods to evaluate system capabilities was demonstrated. Numerical results from CFD simulations were finally verified in experimental tests.

Heat transfer intensification of NEPCM-water suspension filled heat sink cavity with notches cooling tubes by applying the electric field

The effects of an electric field on heat transfer, free convection, and entropy generation of nano-encapsulated phase change material (NEPCM) dissolved in water in a complex inclined chamber are studied. The enclosure consists of a rectangular cavity heated from below and the remaining walls are considered adiabatic. The fluid is cooled by eight cooling tubes, each with four notches. The effects of the electric field, inclination angle (ζ = 45° and ζ = 90°), and Rayleigh number (Ra = 103, 104, and 105) in equal concentration of NEPCM (ϕ = 2 %) are studied using ANSYS Fluent CFD code. The dimensionless form of fluid governing equations, electric potential equation, electric charge density equation, and entropy generation equation are used to set the primitive parameters. Grid verification and validation tests are performed to ensure the reliability of the solution. Calculations show that with increasing Ra, the average Nusselt number (Nuave) decreases from ζ = 45° to 90°, but when an electric field is applied, the results are reversed. As the Rayleigh number increases in conjunction with the electric field, the buoyancy effect becomes more pronounced. Furthermore, owing to its high heat transfer potential and lowest irreversibility, the straight cavity (ζ = 90°) is desirable at Ra = 105.

Design and Determination of Aerodynamic Coefficients of a Tail-Sitter Aircraft by Means of CFD Numerical Simulation

Vertical take-off and landing (VTOL) aircraft have become important aerial vehicles for various sectors, such as security, health, and commercial sectors. These vehicles are capable of operating in different flight modes, allowing for the covering of most flight requirements in most environments. A tail-sitter aircraft is a type of VTOL vehicle that has the ability to take off and land vertically on it elevators (its tail) or on some rigid support element that extends behind the trailing edge. Most of the tail-sitter aircraft are designed with a fixed-wing adaptation rather than having their own design. The design of the tail-sitter carried out in this work had the particularity of not being an adaptation of a quad-rotor system in a commercial swept-wing aircraft, but, rather, was made from its own geometry in a twin-rotor configuration. The design was performed using ANSYS SpaceClaim CAD software, and a numerical analysis of the performance was carried out in ANSYS Fluent CFD software. The numerical results were satisfactorily validated with empirical correlations for the calculation of the polar curve, and the performance of the proposed tail-sitter was satisfactory compared to those found in the literature. The results of velocity and pressure contours were obtained for various angles of attack. The force and moment coefficients obtained showed trends similar to those reported in the literature.

Numerical Investigation of Cooling an Industrial Roller by Using Swirling Jets

Effective cooling of industrial rollers has prime importance to prevent the quality degradation of the system and product. High temperature difference on the roller surface may result in thermal stresses and can cause deformations on roller surface and product. In order to prevent these deformations, cooling of an industrial roller by using swirling jets is investigated for different parameters numerically in this study. Effects of Reynolds number, surface heat flux and variation in inlet temperature of the fluid on the performance of an industrial roller are investigated in terms of temperature difference between inner and outer surface of the roller. ANSYS Fluent CFD program is used to simulate heat transfer and fluid flow in this numerical study. As a result, it is obtained that increasing Re number from 1000 to 1700 causes a decrease of 45.4% in the temperature difference between inner and outer surface of the roller. Increasing surface heat flux from 5000 to 12500 W/m2 has resulted in an increase of 149.4% in difference between inner and outer surface temperature. Increasing coolant fluid inlet temperature from 5 to 20°C has resulted in an increase of surface temperature but there is no significant change in heat transfer characteristics of the system. It is evaluated that the results of this study will contribute to design more effective cooled industrial roller.

Design Analysis of Open and Ducted Propellers in UAV Application

The aim of the study was to determine the feasibility of implementing a ducted propeller system for small scale drones. 5” propeller drones are common in first person view (FPV) drone racing and cinematography, increasing the likelihood of injury due to untrained pilots, of which the majority are laceration injuries due to the propeller blades. Furthermore, the addition of a duct improves the thrust output of the entire system. A few key parameters are identified, of which were manipulated to determine the optimum values through a series of ANSYS Fluent CFD simulations. Introducing a duct is shown to reduce the lift a propeller produces; however, the reduction is offset by the lift generated by the duct. Blade tip clearance was investigated, with the optimum value found to be 0.25 mm, producing the most lift from the duct and least reduction of propeller lift, and with thrust outputs up to 35.568% more in some cases compared to open propeller. It was observed that increasing the BTC significantly reduced duct lift. Diffuser length simulations provided unconclusive results, with the duct lift varying depending on the diffuser length. However, the optimum diffuser length was determined to be 65 mm with respect to thrust outputs. In comparison, inlet lip radius shows a clear pattern, deviating from the optimum value of 16.5 mm reduces the duct lift produced, with smaller values severely decreasing performance.

Heat transfer enhancement for corrugated facing step channels using aluminium nitride nanofluid - numerical investigation

The present work carries out a three-dimensional numerical analysis study of Aluminium Nitride (AlN)-water hybrid nanofluid enhanced heat transfer in laminar forced convection flow heat exchanger with four different channels, flat, backward facing step, triangle and trapezoidal facing step channels. The influence of different Reynolds number (100≤ Re ≤1500) and different solid nanoparticles volume fraction (1% and 4%) on the heat transfer and fluid flow were numerically investigated. The numerical analysis was carried out by using a laminar model of ANSYS-Fluent CFD code and the governing equations were resolved using the finite volume method. The results indicate that the thermal conductivity of the nanofluids increases with the increase values of both the nanoparticles volume fractions and Reynolds number, compared with base fluids. Likewise, the pressure drop showed slightly increased due to the increased of both parameters. The use of high nanoparticles volume fractions (4% volume) nanofluid corresponded with the use of four different channel designs resulted in heat transfer augmentation about 30% when compared to that pure water for the trapezoidal channel.

Study the influence of adding fins to the plate of the solar collector on thermal performance under natural phenomena

To date, most of previous models related to adding fins inside Flat Plate Solar Collector (FPSC) have been carried out under steady-state heat flux and using active-methods for circulating the operating fluid. Therefore, the main purpose of this work is to investigate the thermal response of two developed finned-FPSC models under transient heat flux conditions with using passive systems. The first developed model (model-A-) include straight fins, while the second model with wavy fins (model-B-). Experimental tests are conducted in Baghdad – Iraq, while the numerical results are obtained by using Ansys Fluent CFD. The results indicated that the difference between numerical results and experimental findings is 8.12% for the average water temperature in a tank, while the operating fluid temperature at the exit of the rising pipe is about 8.36%. Furthermore, all new models outperform traditional models in terms of output performance. Moreover, the mass flow rate of model -B- is higher than that of model-A- and traditional models. (Model -B-) was found to be the best model among all others under the current study. The thermal performance of (model -B-) was found to be 16.7% higher than the traditional model in terms of water temperature inside the tank, while the operating fluid temperature at the outlet was increased by 16.2%. In addition, the overall thermal efficiency of the collector for the enhanced (model-B-) is increased by about 20.8% compared to the traditional model. The improved transient model (model-B-) presented in this work shall add a better enhancement to the FPSC behavior of the passive systems.

Analysis of Cylindrical Damper Effects on Turbine Meters Accuracy in a Pulsating CNG Suction Line: An Optimal Design through CFD Simulations

Turbine meters are used in compressed natural gas (CNG) stations in abundance to measure the volumetric flow rate of the inlet gas. These types of meters are very sensitive to oscillating and pulsating flows. When the station’s reciprocating compressor starts to work, due to the piston and valve performance, pulsating flow will create in the suction line and downstream of turbine meter. This pulsation makes false pulses in the meter and finally makes difference between the measured gas flow from the metering of the gas company and the amount of gas that has been sold at the station. In this study, numerical simulation of dampeners has been investigated after turbine meter and before entering gas to compressor. The goal is eliminating or reducing the effects of operating compressor in CNG station on turbine meter and reducing measurement errors. Numerical simulation of dampener was investigated by Ansys-Fluent CFD software for a CNG station with the gas inlet pressure 250 psi, inlet and outlet pipe diameter of 2 inches. In this study, several parameters such as (1) height-to-diameter ratio in the cylinder, (2) distance between dampener and compressor, and (3) volume-to-minimum volume ratio according to API 618, have been checked. The numerical results show that by increasing height-to-diameter ratio up to 3, the pulsating amplitude on Plane 1 will be reduced, and this is the best ratio according to the present results. Also, by increasing the outlet pipe length, the pressure pulsation amplitude decreases from 3.4% of pressure line in 2 m length to 0.7% in 5 m length. Moreover, the results showed 2.4% increase and 1.9% decrease in the maximum and minimum pressure for CV = 1 and CV = 16.7, respectively. Comparing fluent numerical method with previous studies shows less than 2% difference that demonstrates the validity and reliability of present investigation.