Impeller Outlet Width Research Articles

Fast predesign methodology of centrifugal compressor for PEMFCs combining a physics-based loss model and an interpretable machine learning method

For boosted hydrogen fuel cells, the centrifugal compressor greatly affects the system's efficiency, stack power and costs. However, the design of the centrifugal compressor is a lengthy and high-cost process. To tackle this issue, a new method combining a physics-based loss model and a machine learning method was proposed to achieve a fast and more accurate preliminary design step. A high-precision physics-based loss model was developed and validated for data generation. Furthermore, two gradient boosting decision tree (GBDT) models with Bayesian hyperparameter turning were established to construct mapping relationships between geometric parameters and aerodynamic performance. Then, the Sobol sensitivity analysis and Shapley Additive Explanations (SHAP)-based interpretability were used to explore the impact of the geometric parameters on the aerodynamic performances. Results showed that the outlet blade angle, impeller outlet diameter, impeller outlet width, inducer shroud diameter, and inducer blade angle (at the shroud) were the five most sensitive parameters. Additionally, some practical design recommendations were extracted using SHAP-based interpretability. The isentropic efficiencies of two redesign cases with optimal geometric parameters were increased by 2.59% and 1.85% compared with the baseline impellers. The performance prediction was completed within a time of 6 s using the proposed new predesign method. This study represents a significant new attempt to advance the preliminary design methodology of centrifugal compressors.

Impact of Double-Suction Pump Eye Diameter Variation on Cavitation Phenomena

Cavitation phenomena in pumps are major determinants of the lifespan of both the impeller and the pump itself, causing significant vibration and noise, which are critical concerns for pump designers. This study focuses on the influence of various geometric factors of the impeller, including the shape of the blade leading edge, blade inlet angle, number and thickness of blades, surface roughness, wrap angle, impeller outlet width, inlet hub diameter, and tip clearance. The pump analyzed in this study, which exhibited issues of vibration and noise in actual industrial settings, was evaluated by varying only the shroud diameter based on Gulich’s theory, while keeping other parameters constant, to assess the effects on cavitation phenomena across five different impellers. Single-phase analysis was initially conducted to evaluate the performance of each pump model, with the reliability of the numerical analysis methods validated by comparison with experimental data. Furthermore, to analyze cavitation phenomena, a multiphase flow analysis was performed using the Rayleigh–Plesset model within a computational fluid dynamics framework. Quantitative analysis of cavitation occurrence, NPSH3% head-drop performance, and bubble volume was conducted. The results confirmed that the M1 model, featuring a shroud diameter of 560 mm, exhibited superior cavitation resistance. Variations in cavitation occurrence observed under three different flow conditions demonstrated a nonlinear trend, but overall, improvements were noted within a specific diameter range. This study offers valuable insights and data for pump design applicable in real-world industrial settings.

Influence of Impeller Structure Parameters on the Hydraulic Performance and Casting Molding of Spiral Centrifugal Pumps

In order to study the influence of impeller structural parameters on the hydraulic performance and casting moulding of spiral centrifugal pumps, this paper selects a double vane spiral centrifugal pump with a specific rotation number of 170 as the research object. The Plackett–Burman experimental design is used to screen the influencing factors, and the results show that the vane thickness and the impeller outlet width are the significant influencing factors. Based on this result, five different scenarios were set for these two key parameters, numerical calculations were carried out using numerical simulation software for each of the five flow ratio cases, and casting simulations were carried out for the model of each scenario using AnyCasting6.0 to analyze the influence of these two factors on the hydraulic performance and casting forming of the spiral centrifugal pump. It was found that in terms of vane thickness, a moderate increase in vane thickness improved the hydraulic performance at small flow rates, but an excessive increase at large flow rates led to a decrease in efficiency and an increase in the probability of casting defects. In terms of impeller outlet width, increasing the outlet width caused the design point to be shifted, leading to a decrease in efficiency at small flow rates, but an increase in efficiency when the design flow rate was higher. At the same time, increasing the outlet width makes casting defects more likely to occur at the blade and back cover joint than on the blade surface. The study in this paper clarifies the significant effects of these two parameters on the performance and casting quality of spiral centrifugal pumps, and provides guidance for the optimal design of spiral centrifugal pumps.

Optimization of Hydraulic Efficiency and Internal Flow Characteristics of a Multi-Stage Pump Using RBF Neural Network

In order to improve the hydraulic efficiency and internal flow pattern of a multi-stage pump under multiple flow conditions, an intelligent optimization design was proposed for its hydraulic components. Sensitivity analysis was used to select the key parameters influencing the hydraulic efficiency of a multi-stage pump. The optimal Latin hypercube sampling and non-dominated sorting genetic algorithm Ⅱ were employed to build a multi-objective optimization system. Moreover, a radial basis function neural network was adopted as the surrogate model of hydraulic efficiency. The research results showed that the impeller outlet width, impeller blade wrap angle, impeller outlet blade angle, and diffuser inlet width were the key factors affecting the hydraulic efficiency. The efficiency of the optimized model increased by 4.35% under the design condition and the matching of the internal flow between the optimized impeller and diffuser was significantly enhanced under the nominal condition. The improved flow pattern could be clearly observed in the flow passage of both the pump impeller and the diffuser. After optimization, the wear performance of the model was also improved compared to the original design. The wear area decreased in size and was distributed more evenly, resulting in a noticeable decrease in the maximum amount of wear.

Optimization design of hump phenomenon of low specific speed centrifugal pump based on CFD and orthogonal test

Aiming to eliminate the hump phenomenon in a low specific speed centrifugal pump, its structural parameters were optimized using the computational fluid dynamics method. Based on the k - varepsilon turbulence model, a 3D steady analysis of the internal flow field was carried out. The L_{9} left( {3^{4} } right) orthogonal table was established, and four structural parameters, including the impeller outlet diameter, impeller outlet width, number of blades, and blade outlet angle, were selected as influencing factors. Nine orthogonal test schemes were developed and the results were analyzed through the weight matrix analysis method, obtaining the weight of the selected factors on the test results. The optimal scheme was selected according to the weight and the weight matrix analysis results have shown that the impeller outlet width had the dominant influence on the head, shaft power, and efficiency. Further, the blade number was the main influencing factor for shaft power and efficiency. The centrifugal pump flow control test bench was built to carry out the numerical simulation and test all the prototype and optimization pump indexes. Through the external characteristic test, it can be seen that the beta_{2} Z^{0.773} of the optimized pump is 87.889, which is 24.89% lower than that of the prototype pump, which effectively optimizes the hump phenomenon of the centrifugal pump. The experimental results have shown that in underrated working conditions, the working performance of the optimized pump was improved significantly. The head size was reduced by 1.424%, and the efficiency was increased by 7.896%. By optimizing the structural pump parameters, its jet-wake hydraulic loss was reduced, and the head curve hump phenomenon was effectively eliminated. All the performance indexes of the optimized pump were higher than those of the prototype, verifying both the accuracy and reliability of the orthogonal test and weight matrix analysis method. Finally, obtained results provide a reference for the structural design of high-performance centrifugal pumps.

The Cavitation Characteristics of High Speed Centrifugal Pumps With Different Impeller Types

Addressing the cavitation prevention requirements for a longer service life of the high-speed centrifugal pump in the temperature control system of aerospace, the effect of blade inlet width on cavitation performance is studied on the premise of consistency of impeller outlet diameter D2, impeller outlet width b2, volute inlet diameter D3, pump interface and other structural parameters. Therefore, the corrected coefficient k1 of blade inlet exclusion coefficient is introduced; four groups of centrifugal impellers with inlets of different geometric structures blades are put forward. To begin with, based on the D# pump performance test and Pumplinx simulation, the cavitation performance of high-speed pump with four different groups of impellers is studied under five working conditions of negative inlet pressure (Pj=(−20, −30, −40, −50, −60)kPa) on the premise that energy characteristics agree well with cavitation performance. According to the results, when Pj drops from −50 kPa to −60 kPa, the cavitation perform changes the most significantly. This indicates that the method of twisting the centrifugal impeller of the suspended forward-extended blade shows a significant effect in preventing cavitation performance under such working conditions of high speed and negative pressure. Its application in aerospace power systems can effectively reduce the impact of low pressure in the system and significantly improve the cavitation performance.

Investigation of the Effect of the Stages Number, the Impeller Outlet Width, and the Impeller Outlet Angle on the Performance of an Industrial Electric Submersible Pump

Abstract This study has investigated the effect of the number of stages, the blade outlet spacing, and the blade outlet angle of a selected industrial submersible pump on the pump performance. The main steps in the study are outlined below: Firstly, the operating characteristics in different stages of a selected industrial submersible pump were measured by the experiment. Following the measurements, the effects of two basic geometric parameters, such as impeller outlet width and impeller outlet angle on the pump performance were examined with computational fluid dynamics (CFD) simulations verified by the experimental measurements. It was seen that the geometric parameters, which were considered in the simulations, changed the size of the time-dependent variables, but the flow structure did not. Another striking finding from the CFD simulations carried out is it has been observed that while geometric arrangements have a partial effect on the flow structure along with the pump, they cause a difference in the critical values on the basic variables that define pump performance, such as pressure.

Investigation on Broadening Compressor Surge Margin by Using Active Magnetic Bearing

The impeller design usually expects to achieve high efficiency and a wide working range while they are influenced by tip clearance in different ways. In this study, a blower with a controllable magnetic suspension bearing was studied. The magnetic bearing enables the impeller to adjust the tip clearance during operation to optimize the efficiency of the blower at the design point and significantly expand the surge margin when it deviates from the design point. The clearance ratio (CR) is defined as the ratio of tip clearance over impeller outlet width. The computational fluid dynamics (CFD) method is used to study the performance of a centrifugal impeller under CR = 2.61%∼7.83% and verified by experiments. The results show that the pressure ratio and efficiency of the impeller at the design point decreased linearly with the increase of the gap. For each 1% increment in CR, the pressure ratio reduces by 0.02 and the polytropic compression efficiency declines by 0.5%. Conversely, the surge margin increases with the expansion of CR. For every 1% rise in CR, the surge margin would improve by 7.8%. A control method of changing the reference suspension position according to the optimal efficiency fitting model is proposed. It realizes the real-time control of the axial suspension position of the impeller according to the changes of pressure and flow rate signals to obtain the optimal work efficiency with a broad surge margin. Experimental results show that using an impeller equipped with a controllable magnetic suspension bearing could minimize the gap stably in the nonsurge area to obtain high efficiency, and when necessary, it could enlarge the gap to meet the low flow rate condition.

Optimization Design and Internal Flow Field Study of Open‐Design Vortex Pump

To determine the influences of the main structural parameters on open‐design vortex pump performance, optimize the vortex pump performance, and reduce the running vibration and improve stability, orthogonal testing method was introduced in this paper. The selected main factors included impeller outer diameter (D2), impeller outlet width (b2), outlet setting angle of impeller (β2), and inlet setting angle of impeller (β1), and the nine types of impellers were coded according to orthogonal table. After obtaining the preliminarily optimum value range for each factor through range analysis, comprehensive analysis was employed based on the orthogonal test to investigate the main factors and identify the primary and secondary influencing factors affecting the performance of the vortex pump. An optimization scheme was obtained for further design. The results show that the numerical calculation results of the optimization scheme pump are in good agreement with the test results, and it shows the feasibility of the numerical calculation method. The testing results showed that efficiency and head of the optimal model were 4.2% and 9 m higher than those of the prototype model, respectively. Improved efficiency and head met the design requirements. The orthogonal testing method proved the feasibility of performance optimization of the vortex pump. The backflow occurs at the pump entrance and rotates in the same direction with impeller. It moves along the pipe wall from the lateral cavity to the inlet and encourters with the approaching flow.

A new method for performance map prediction of automotive turbocharger compressors with both vaneless and vaned diffusers

A new approach to predict the performance maps of automotive turbocharger compressors is presented. Firstly, a polynomial equation is applied to fit the experimental data of flow coefficient ratios for the centrifugal compressors with both vaneless and vaned diffusers. Based on this equation, the choke and surge flow coefficients under different machine Mach numbers can be quickly predicted. Secondly, a physically based piecewise elliptic equation is used to define compressors’ characteristic curves in terms of efficiency ratio. By introducing the flow coefficient ratio into the efficiency correlation, the empirical coefficients in the piecewise elliptic equation are uniquely calibrated by the experimental data, forming a unified algebraic equation to match the efficiency maps of the compressors with both vaneless and vaned diffusers. Then, a new universal equation, which connects the work coefficient, the impeller outlet flow coefficient and the non-dimensional equivalent impeller outlet width, is derived by using classical aerothermodynamic method. The off-design pressure ratio is predicted based on the equivalent impeller outlet width with less knowledge of the compressor geometry and no empirical coefficients. Finally, three state-of-the-art turbocharger compressors (one with vaneless diffuser, two with vaned diffusers) are chosen to validate the proposed method, and the results show a satisfactory accuracy for the performance map prediction. This method can be used for the preliminary design of turbocharger compressors with both vaneless and vaned diffusers, or to assess the design feasibility and challenges of the given design specifications.

Design Optimization of the Impeller and Volute of a Centrifugal Pump to Improve the Hydraulic Performance and Flow Stability

Abstract Multi-objective design optimization was applied to the impeller and volute of a centrifugal pump using surrogate-based optimization techniques and three-dimensional Reynolds-averaged Navier–Stokes (RANS) analysis. The objective functions used to improve the hydraulic performance and operating stability of the pump were the hydraulic efficiency at the design condition and the flow rate at which the maximum volute pressure recovery coefficient occurs. Three design variables were selected based on the results of a sensitivity analysis: the blade outlet angle, the constants in determining the impeller outlet width, and the cross-sectional area of the volute. Using response surface approximation (RSA), surrogate models were constructed for the objective functions based on numerical results at experimental points obtained by Latin hypercube sampling (LHS). The representative Pareto-optimal solutions obtained by the multi-objective genetic algorithm (MOGA) show enhanced objective function values compared to the baseline design. The results of unsteady calculation show that the flow instability of the centrifugal pump was successfully suppressed by the optimization.

Numerical Simulation of Centrifugal Pump and Effect of Impeller Geometry on Its Performance

In the presented paper, the effect of impeller geometric parameters on the performance of centrifugal pump has been investigated. This study was performed for different flow rates and rotational speeds, allowing to obtain the performance curve for the centrifugal pump. Three dimensional computational fluid dynamic simulation of the impeller and volute for a centrifugal pump has been performed using ANSYS CFX software (a high-performance computational fluid dynamics software tool that delivers reliable and accurate solutions). The pump has an outside impeller diameter of 205 mm, impeller outlet width of 16 mm, rotational speed 1450 rpm, seven impeller blade and a specific speed of 28. By increasing the impeller outer diameter and outlet width, both net head and power consumed are increased. In addition, it was noticed that the best efficiency point (BEP) was achieved at volume flow rate higher than design flow rate. The performed simulations indicated that; by changing the impeller outer diameter from 200 mm to 210 mm, the flow rate of BEP increases about by 14.7%. By changing the impeller outlet width from 14 mm to 18 mm, the flow rate of BEP increased by about 9%, and the efficiency of BEP reduced by approximately 0.5%. It was also noticed that, increasing the rotational speed will cause an increase in the net head and consumed power. An increase of 13.8% for the flow rate of BEP was observed when changing the rotational speed from 1400 rpm to 1500 rpm, with the same BEP.

Multiobjective Optimization Design and Performance Prediction of Centrifugal Pump Based on Orthogonal Test

In order to improve the hydraulic performance of the centrifugal pump, based on the original model, the optimization mathematical model with the four indexes head, efficiency, shaft power, and pump net positive suction head as objective function was established, and the multiobjective optimization design of the centrifugal pump was carried out by orthogonal test. Based on the L16(44) orthogonal table, 16 sets of orthogonal test schemes were made by selecting the four parameters impeller outlet width, blade inlet angle, blade outlet angle, and cape angle; the flow field numerical simulation was carried out by computational fluid dynamics technique; and the influence order of geometric parameters on optimization indexes was obtained by range analysis. The weight of each test factor on the optimization index was calculated by weight matrix, and a set of optimal schemes was obtained. Based on the external characteristic experimental bench of the IH 65‐60‐190 chemical centrifugal pump, the simulation values and test values of the prototype pump and the optimization pump were obtained under different working conditions. Under the rated flow, the head was reduced by 17.00%, the efficiency was increased by 9.14%, the shaft power was reduced by 21.50%, the pump net positive suction head was reduced by 16.69%, the curve hump was eliminated, the performance of centrifugal pump was improved, and the feasibility of the weight matrix optimization method was verified. The particle image velocimetry measurement system was used to measure the relative velocity of the internal media in the centrifugal pump. The results showed that the optimization pump had no obvious “jet‐wake” flow structure, its maximum velocity was less than the prototype pump, the area of low‐speed zone was larger than the prototype pump, the efficiency of the centrifugal pump was improved, and the shaft power and pump net positive suction head were reduced. The reason of the head decrease was analyzed from the internal flow situation, and the accuracy of the design optimization process was proved.

Analysis of effect of impeller geometry including blade outlet angle on the performance of multi-pressure pumps: Simulation and experiment

In this paper, the effect of outlet angle geometry of the blades of the impeller of a multi-pressure pump on the pump’s head and efficiency using two approaches, namely numerical approach (Computational Fluid Dynamics) and experimentation are investigated. Herein, a closed single-suction, five-blade impeller with three different outlet angles (27°, 30°, and 33°) is analyzed. The impeller model was first built in SOLIDWORKS software before analyzing the fluid flow with the help of ANSYS Fluent software. All surfaces were meshed through irregular gridding. Considering high flow velocity along with low thickness of boundary layer near the blade tips, smaller mesh sizes were used across these areas. Blade surfaces were meshed using square elements. Furthermore, in order to model the volumes, irregular gridding and TGrid algorithm were undertaken. Generated with this algorithm are quadtrial elements of known size. In volumetric meshing stage, aspect ratio was set to a maximum of 0.6. In the experimentation phase of this research, a multi-stage pump was tested at 2000 rpm and 30 kW of input power with three impellers of different angles. At specific values of outlet angle and impeller outlet width, some reductions in hydraulic and mechanical losses within the impeller along with some rises in the pump head and efficiency were observed. Simulation results were found to be in good agreement with the experimental data; so as one can save time and money by using numerical simulation approaches in ANSYS Fluent rather than undertaking experimentations. Numerical and experimental analyses revealed that the maximum pump head and efficiency have been witnessed at the outlet angle of 30°. This is because of the reduced losses by water recirculation within the volute and outlet impellers.DOI: http://dx.doi.org/10.5755/j01.mech.23.1.17676

Numerical computation of the flow noise for the centrifugal pump with considering the impeller outlet width

In order to study the effects of the impeller outlet width on the flow noise of the centrifugal pump, a centrifugal pump is applied in the paper as the research object. Geometric parameters of the pump and impeller are constant, and BEM (Boundary Element Method) and experimental method are adopted to analyze noises when the impeller outlet width is 8 mm, 10 mm, 12 mm and 14 mm, respectively. Firstly, Large-eddy simulation method is applied to compute the transient flow field of the centrifugal pump. Larger pressures and flow velocity of the centrifugal pump mainly are at the edge of the impeller. When the fluid flows from the centrifugal pump, there are two obvious separation vortexes at the outlet of the centrifugal pump. The flow velocity distribution of the centrifugal pump in the horizontal plane is basically symmetric. Based on modal analysis and the transient flow field of the pump, BEM is adopted to compute the noise in the centrifugal pump caused by the unsteady flow, and experiments are also conducted for verification. Based on the above analysis, the noise in the interior and exterior field of the centrifugal pump is computed, and the effects of the impeller outlet width on the noise of the centrifugal pump are then studied. As shown from the result, the radiation sound power at the characteristic frequency increases with the increase of the impeller outlet width. With a reasonable range, the impeller outlet width makes the sound pressure level (SPL) in the interior and external field of various flow conditions be smaller. Considering the energy performance and flow field noises of the centrifugal pump, the pump has the optimal comprehensive performance at the impeller outlet width of 10 mm. The research results can be applied to provide a reference for the optimization design of the centrifugal pump with low vibration and noise.

Analysis of the impact of impeller outlet width on the steepness of pressure characteristic

The impeller outlet width is one of the most important geometrical parameters, which has a significant effect on the pressure characteristic of centrifugal pumps. The steepness of the pressure characteristic, in turn, determines selection of the pump control in the system. Finding a mathematical dependency between them will make it possible to design the impellers of centrifugal pumps with a predetermined steepness. To find the dependence between the impeller outlet width and the steepness of a pressure characteristic, we carried out numerical simulation. 30 double-entry impellers of centrifugal pumps with a specific speed from 80 to 210 with different values of the width of the impeller were simulated. Using numerical modeling data, we established dependences between the impeller outlet width b 2 and the steepness of the pressure characteristic K H , and also consumable parameter q р , of the viewand . The coefficients a, k, E and F in the equations are variable and depend on the design features of Impeller. In order to use the established dependencies in the design of any double-entry impellers, it is necessary to determine the main geometric parameters of the impellers, which greatly influence the coefficients a, k, E and F.

Hydraulic Analysis of Vertical Turbine Pump

Pumping is the process of adding energy to the fluid to move it from one point to another. The main task faced by an engineer while drawing a pump design is with meeting the ends with the economics and the hydraulic operating characteristics. Computational Fluid Dynamics (CFD) has been widely used in analysis of 3D complex fluid flows present inside the pump hydraulic passages. The hydraulic analysis of a Vertical Turbine pump is performed using CFX software. CFturbo software has been used to predict the initial design of pump geometry. The overall goal of this work is to study the streamline and contours of pressure and velocity in a Vertical Turbine pump (Impeller and Bowl). The hydraulic performance of the pump is affected by geometrical parameters like Eye Diameter, Impeller outlet diameter, impeller outlet width etc.

Numerical Research on Hydraulically Generated Vibration and Noise of a Centrifugal Pump Volute with Impeller Outlet Width Variation

The impeller outlet width of centrifugal pumps is of significant importance for numbers of effects. In the paper, these effects including the performance, pressure pulsations, hydraulically generated vibration, and noise level are investigated. For the purpose, two approaches were used to predict the vibration and sound radiation of the volute under fluid excitation force. One approach is the combined CFD/FEM analysis for structure vibration, and then the structure response obtained from the FEM analysis is treated as the boundary condition for BEM analysis for sound radiation. The other is the combined CFD/FEM/BEM coupling method. Before the numerical methods were used, the simulation results were validated by the vibration acceleration of the monitoring points on the volute. The vibration and noise were analyzed and compared at three flow conditions. The analysis of the results shows that the influences of the sound pressure of centrifugal pumps on the structure appear insignificant. The relative outlet widthb2*atnq(SI) = 26.7 in this paper should be less than 0.06, based on an overall consideration of the pump characteristics, pressure pulsations, vibration and noise level.

Research of factors influencing centrifugal pump external characteristics based on orthogonal test

In order to investigate the impact on external characteristics of single-stage and single-suction centrifugal pump, four parameters: cutwater gap(δ), blade number(z), impeller outlet width(b) and blade outlet angle(β) were taken into account. Orthogonal test method is a method which can make a comprehensive comparison among factors we are interested in. Thereby, it can't be more appropriate to adopt this approach to study the influence of the four factors referred above. Based on the prototype pump's geometric parameters, each of these factors took four levels. According to the principle of selecting orthogonal array, the L16(45) array was selected and 16 models were designed. After that, commercial CFD software CFX was used to calculate the head and efficiency under different conditions to determine the optimal operating condition Qr. The 16 models' rated flow rates were basically smaller than the prototype's. Considering this difference, in order to analyze the influence on the head under similar condition, the flow rate was made dimensionless and 3 conditions are chosen(Qr/Q=1, 1.25 and 1.375). Through the analysis of averaged respond head and efficiency, the laws of head and efficiency changing with the variation of the factors were obtained. Commonly, if a dependent's change cause by a independent variable is smaller than 5%, we can neglect the independent variable's effect. Thus the paper presents a research showing the factors' changing limitations considering the head changing by a percentage smaller than 5%. The conclusion of this article has important reference value for design of centrifugal pumps.

Multi-objective optimization design and experimental investigation of centrifugal fan performance

Current studies of fan performance optimization mainly focus on two aspects: one is to improve the blade profile, and another is only to consider the influence of single impeller structural parameter on fan performance. However, there are few studies on the comprehensive effect of the key parameters such as blade number, exit stagger angle of blade and the impeller outlet width on the fan performance. The G4-73 backward centrifugal fan widely used in power plants is selected as the research object. Based on orthogonal design and BP neural network, a model for predicting the centrifugal fan performance parameters is established, and the maximum relative errors of the total pressure and efficiency are 0.974% and 0.333%, respectively. Multi-objective optimization of total pressure and efficiency of the fan is conducted with genetic algorithm, and the optimum combination of impeller structural parameters is proposed. The optimized parameters of blade number, exit stagger angle of blade and the impeller outlet width are seperately 14, 43.9°, and 21 cm. The experiments on centrifugal fan performance and noise are conducted before and after the installation of the new impeller. The experimental results show that with the new impeller, the total pressure of fan increases significantly in total range of the flow rate, and the fan efficiency is improved when the relative flow is above 75%, also the high efficiency area is broadened. Additionally, in 65% −100% relative flow, the fan noise is reduced. Under the design operating condition, total pressure and efficiency of the fan are improved by 6.91% and 0.5%, respectively. This research sheds light on the considering of comprehensive effect of impeller structrual parameters on fan performance, and a new impeller can be designed to satisfy the engineering demand such as energy-saving, noise reduction or solving air pressure insufficiency for power plants.