Inlet Blade Angle Research Articles

Collaborative Robust Design Optimization of Blade Geometry and Manufacturing Tolerance for a Transonic Centrifugal Impeller

Abstract Turbomachinery components are inevitably subjected to various sources of manufacturing errors. The resultant variations in blade geometry eventually lead to performance degradation. This is especially true for transonic centrifugal compressor impellers where the complex interaction between the geometric variations and shock waves may amplify such degradation. However, relevant studies on uncertainty quantification or robust design optimization of centrifugal impellers are quite rare. The mechanisms of how the realistic manufacturing errors influence the impeller aerodynamic performance are not clear. In addition, most existing studies have considered a fixed level of manufacturing tolerance applied to the impeller blade surface, which neglects the combined effect of blade geometry and manufacturing tolerance on impeller performance. In this study, a collaborative robust design optimization was performed for a transonic centrifugal impeller considering realistic manufacturing errors. The realistic manufacturing error field was first modeled based on the measurements of 92 centrifugal impellers. With a combination of computational fluid dynamics simulation and the non-intrusive polynomial chaos method, the influence of manufacturing errors on impeller performance and flow field variations was quantified. To save computational costs for the uncertainty quantification, a dual dimensionality reduction method was proposed to reduce the dimensionality of uncertainties. Finally, blade angles and the manufacturing tolerance of the impeller were collaboratively optimized to enhance the impeller performance robustness against manufacturing errors. The results show that the impeller aerodynamic performance exhibited a downward trend in the presence of manufacturing errors. The flow mechanisms responsible for this trend were mainly associated with increased intensity of the shock waves near the inducer blade tip. Such shock waves were significantly alleviated by reducing impeller inlet blade angles without the loss of pressure rise capability. Consequently, the impeller performance robustness against manufacturing errors was enhanced with the standard deviation of polytropic efficiency being reduced by 35% at a lower anticipated manufacturing cost due to increased tolerance allowance.

MODELLING STUDIES USING CORROSIVE AND NON-CORROSIVE MATERIALS TO IMPROVE ON RELIABILITY AND EFFICIENCY OF AN IMPELLER OF A CENTRIFUGAL PUMP.

The quest to improve on the reliability, operability, sustainability of centrifugal pumps in all facets of process operations which includes; oil and gas industries across the globe have a pivoted role to play in the development of world energy technology and sustainability in numerous ways. This is because several operability challenges and malfunctioning of centrifugal pumps can usually results to unexpected shutdown of process operations and mostly in cases with faulty standbys. Several researches have been conducted using experiment and numerical simulations to design the centrifugal pump impellers. As a result of recent research, the performance of contemporary centrifugal pump impellers yielded positive results. However, for sustainability there is a need to design the impellers using corrosive and non-corrosive materials to improve on its reliability and efficiency of the pump impeller is one of the key design parameters of the centrifugal pump, which has an important influence on the internal flow field and performance of centrifugal pump. In this paper, impeller models with different blade inlet and outlet angles (350 - 47°, 380 - 50°, and 410 - 53°) were designed via vista CPD under the basis of impeller parameters used, and numerical simulation was carried out in the commercial software ANSYS-CFX. Then the experiment was performed on three processes, that is, pre-processing, the solver and post-processing using corrosive fluids (Saline water, hydrochloric acid, methanol) and non-corrosive fluids (water at 1000C, gasoline, kerosene) to improve on reliability and efficiency of the impeller of centrifugal pump. The results of the pressure of impeller inlet first decreases and then increases, and the change trend of pressure distribution is consistent under different inlet and outlet angles and different corrosive and non-corrosive fluids. It can be seen that the relative velocity of the fluid in the impeller increases gradually, and the velocity has minimum value and smaller gradient in uniform flow at the impeller inlet. The performance of the impeller was simulated to improve is the reliability and efficiency for corrosive and non-corrosive fluids with different mass flowrate and head rise of 55m and various efficiency ranging from 67.55% to 94.21%. To verify the numerical result and analysis, the performance test apparatus for the centrifugal pumps was designed and built for further researches, and all the research results could provide appropriate reference for designers to select reasonable outlet angle. Keywords: Oil and gas, centrifugal pump, reliability, sustainability

A Comparative Study of Impeller Modification Techniques on the Performance of the Pump as a Turbine

The extensive use of the pump as a turbine (PAT) for micro-hydropower applications has a significant value from economic and technical viewpoints. However, the unavailability of the characteristics curve and relatively lower efficiency are the two basic limitations when considering pumps for power-generating applications. In this paper, the performance of the PAT is analyzed using the computational fluid dynamics (CFD) software called Ansys CFX in conjunction with standard k - ε . Then, experiments were done to verify the results of the simulation. Measurement inaccuracy effects are also taken into account. The initial performance of the PAT is refined by controlling basic design parameters (i.e., increasing the number of impeller blades, decreasing blade thickness, blade tip rounding, and adjusting blade inlet angle). Additionally, a new modification method known as blade grooving is also introduced in this research. Finally, all listed modification techniques are applied simultaneously to achieve maximum performance. The output of the study confirms that the adopted modification techniques have a positive effect on performance improvement. When the number of impellers is increased, the power output is enhanced by 5.72%, and blade grooving provides the most efficiency improvement, i.e., 7.00%. But decreasing blade thickness has no remarkable impact on the performance; the power output and efficiency are improved by 1.24% and 2.60%, respectively. The maximum performance improvement was achieved when the modification techniques are applied simultaneously with 10.56 and 10.20 percent of power and efficiency increments, respectively. From the entire study, it can be concluded that the chosen design parameters have an important effect on stabilizing the internal flow, decreasing the required head, decreasing the hydraulic loss in the impeller, and increasing the overall performance. The study also helps to figure out which modification technique is the most practical.

Optimization of geometric parameters of hydraulic turbine runner in turbine mode based on the orthogonal test method and CFD

The hydraulic turbine in turbine mode (TMHT) with ultra-low specific speed is a new type of energy recovery device for recovering energy stored in the high-pressure fluid. In order to solve the problem of insufficient consideration of runner geometric parameter optimization, this paper proposes an optimization strategy (OT-CFD), which is based on the orthogonal test method and computational fluid dynamics (CFD), to optimize the performance of the TMHT runner. Firstly, the orthogonal test schemes are established with 5 levels of runner inlet diameter, outlet diameter, inlet height, blade inlet angle, and blade number. Then 25 three-dimensional models of two-stage TMHT containing flow passage components such as Francis runner are built. Further, the internal flow characteristics and energy characteristics of TMHT are calculated and then verified by the real machine test. By comparing the numerical simulation results, the design schemes of runner geometry parameters corresponding to the highest head (H) and the highest efficiency (η) are determined, respectively. On this basis, the optimization effect of runner geometry parameters is analyzed by numerical simulation based on CFD. In conclusion, the inlet angle is the most important factor affecting the efficiency, and the runner inlet diameter is the most important factor affecting the water head. Compared with the comparison scheme, the optimal η scheme has a more stable flow pattern, which provides an efficiency increase of 10.9%, a water head increase of 26.75 m, and a power increase of 646.32kW, greatly reduces the energy loss in the process of residual pressure recovery; the optimal H scheme has an efficiency increase of 2.61%, but more stable and regular flow pattern. More importantly, the optimal water head scheme, which has a water head increase of 185.53 m and a power increase of 1518.3kW, greatly increases the capacity of recovering the water head.

Optimization of energy recovery turbine in demineralized water treatment system of power station by Box–Behnken Design method

In order to improve the recovery efficiency of the energy recovery turbine in the demineralized water treatment system of the power station, the Box–Behnken Design (BBD) response surface method combined with CFX numerical simulation were used to calculate the outlet angle of the turbine impeller blade(β1),blade inlet angle(β2), blade thickness(h), which were selected as the three factors of BBD test design, and head H and efficiency η were two evaluation indexes, the design-exper10 software is used to test and analyze the test results, then the whole flow field of the optimized turbine model was analyzed with CFX numerical simulation. The results show that when the β1 and β2 are 24.6° and 22.4° respectively, and h is 3.8 mm, the turbine has the optimal hydraulic performance. The efficiency of the optimized turbine model is increased by 1.8% and the head is increased by 21 m under rated working conditions. The research may provide a good basis for the energy-saving transformation of demineralized water treatment system in power station.

Experimental study of centrifugal pump as turbine with S-blade impeller

As a hydraulic energy recovery device, pump as turbine(PAT) has been applied widely in the seawater desalination and petrochemical industry. In order to improve the hydraulic performances, the blade inlet angle was redesigned by analyzing the velocity triangle of PAT impeller inlet, and an S-blade was proposed. Then, A new S-blade impeller was obtained by optimizing the impeller in a real case of centrifugal pump as turbine application, and it was compared with the original impeller through experiments. The results show that the efficiency of the new S-blade impeller is around 3% higher than that of the original blade with the fixed flow rate and head. Under the fixed speed, the shaft power of the new S-blade impeller is higher than that of the original blade, and the maximum deviation is 0.75 kW. The study could have important directive significance to blade optimization of PAT.

Optimization Design for the Centrifugal Pump under Non-Uniform Elbow Inflow Based on Orthogonal Test and GA_PSO

The non-uniform inflow caused by the elbow inlet is one of the main reasons for the low actual operation performance of a centrifugal pump. Orthogonal experiment and GA_PSO algorithm are used to improve the head and efficiency of a centrifugal pump with an elbow inlet based on the method combining numerical simulation and prototype experiment in this paper. The effects of the design parameters, including elbow inlet radius ratio, blade inlet angle, blade number, blade wrap angle, blade outlet angle, impeller outlet diameter, blade outlet width and flow area ratio, on the pump head and efficiency are studied in the orthogonal experiment. The blade inlet angle is the major factor to match the non-uniform inflow and reduce the flow loss in the impeller inlet to contribute to enhancing the pump performance and cavitation characteristics. The particle swarm optimization (PSO) algorithm is optimized by integrating the genetic algorithm (GA), which ensures that the PSO-calculation result avoids falling into the local optimization and the global optimal solution is obtained as quickly as possible. The centrifugal pump with an elbow inlet is optimally designed by the GA_PSO algorithm. According to the performance test results, the efficiency of the optimized pump is 4.7% higher than that of the original pump.

Effect of impeller inlet diameter on saddle-shaped positive slope and non-uniform flow patterns at low flow rates of a mixed-flow pump

Most mixed-flow pumps obtain a saddle-like Q-P curve with a backflow, owing to the increased incidence angle at low flow rates. The backflow was developed near the shroud and followed downstream again at its end to form a recirculating flow. The rotating stall, which could be a part of the recirculating flow, followed the impeller’s rotational direction, and its properties affected the local stability. The reattaching flow became strong when the upstream flow from the blade leading edge deviated from the same circumferential degree as the dominant flow of the rotating stall heading downstream. The fluctuation in the total pressure rise decreased when the average incidence angle was smaller than that of the design flow rate. As a passive control to suppress the saddle and the above flow patterns, the impeller inlet diameter was reduced from the shroud, and the inlet blade angle was further adjusted to maintain the incidence angle. From the reduced inlet diameter, the backflow was mostly suppressed, and the saddle was improved with a wider operating range. Here, the performance near the design flow rate was almost maintained. The stability was evaluated using the fast Fourier transform, and the numerical method was validated through experimental tests.

Influence of Geometric Variations of an Inlet Cover Bleed System on Inducer Performance for an Axial Pump Operating Under Cavitating Conditions

AbstractA stability control device (SCD) is a passive inlet cover treatment that can be applied to high suction performance inducers. Significant improvements in stability have been observed when an inducer operates with an SCD, including suppression of backflow at the leading edge of the inducer at low off-design flow coefficients. This is possible because of a local increase in mass flow at the leading edge of the pump, which allows an inducer to operate with an incidence near the design point value over a wide range of flow coefficients. In this paper, the suction performance of several inducers was explored with several different SCD geometries and at different flow coefficients. Specifically, five different SCD geometries were considered to explore the influence that SCD bleed slot width and resistance to flow through the SCD channel have on inducer performance. Further, removal of tangential velocity of the energized fluid transporting through the SCD channel was considered for some scenarios to highlight the impact of swirl on inducer performance. The results reveal that for all inducers and SCD combinations considered, the most important factor affecting the mass flow through the SCD, and subsequent mass flow gain, is the inlet diffusion of the inducer. This holds for both single-phase and multiphase scenarios. Further, the cavitation number where cavitation first starts to develop in the blade throat passage of the inducer is primarily dependent on the inlet blade angle and not the SCD geometry. Consequently, the shape of the cavitation breakdown curve is largely determined by the inducer blade angle.

Geometry scaling technique and application to aerodynamic redesign of multi-stage transonic axial-flow compressors

Geometry scaling technique, as one of the essential steps in aerodynamic redesign of multi-stage compressor, directly determines whether the new scaled geometry meets the required performance or not. It is also one of the effective measures in unsteady flow simulation of multi-stage compressor to reduce greatly the computational cost by scaling the computational domain from full-annulus passages to partial-annulus passages. The common critical issue arisen from both practices is the geometry dissimilarity in which some certain difference exists between the original and scaled geometries due to a diversity of redesign requirements or model simplifications. However, the extent of how the geometry dissimilarity influences the aerodynamic performance of multi-stage transonic compressor is unclear up to now. Particularly, how to keep the aerodynamic performance similarity in the case of geometry dissimilarity has not been explored yet. Here we propose a geometry scaling technique in which 3D parametric geometry modeling and 1D mean-line analysis are combined to define a series of key redesign criteria in order to keep as minor as possible variations in the aerodynamic performance of multi-stage compressor. The proposed technique is applied to redesign a 3.5 stage transonic axial-flow compressor with two geometry scaling strategies, i.e., adjustable blade/vane numbers and inlet guide vane (IGV)-rotor-stator axial spacing. The key aerodynamic parameters determined by the key redesign criteria are then quantified to verify the feasibility and accuracy of the proposed technique by computational fluid dynamics (CFD) simulations. The results show that by keeping the similarity of key redesign criteria, that is, blade solidity, stagger angle, inlet blade angle, outlet blade angle and thickness to chord distribution, the similarity of key aerodynamic parameters (incidence angle, deviation angle, loss coefficient and aerodynamic blockage) and thus of overall aerodynamic performance (mass flow rate, pressure ratio and efficiency) can be generally guaranteed. The variations of aerodynamic performance in the case of geometry dissimilarity with different blade/vane numbers and IGV-rotor-stator axial spacing are generally within 1%. Compared against the similarity of the other key aerodynamic parameters, a certain dissimilarity of aerodynamic blockage is observed, impacting slightly on the mass flow rate and thus stall margin. The present work is of effective assistance to improve the redesign methodology for multi-stage axial-flow compressors.

A study on the effect of blade inlet angle, attack angle and the diameter ratio on the efficiency of a Banki Mitchell turbine

In the present work, a theoretical investigation is presented on how the efficiency of a Banki Mitchell turbine is affected by its design parameters. With the help of general formulation of the control volume theory to the equation of the moment of momentum in the turbine’s runner and considering all assumption regarding the properties of the flow and the design geometry of the runner, a mathematical model has been developed. The water discharge through the turbine is considered incompressible, non-viscous, homogenous and steady flow; The loss due to shock on the inner and outer surface of the runner as well as leakage losses are neglected. As results of the present study, the behaviour of hydraulic efficiency was determined when varying the angle of attack, the blade entry angle as well as the runner diameter ratio, indicating their appropriate values in each different scenario. In this paper critical relationships between design parameters have been disclosed and therefore analysed and simulated using Simulink MATLAB. Furthermore, it was mentioned that for a better performance, the exit angle of the blade should be 90°. At length, an expression was given estimating the turbine’s efficiency at various operating conditions and for calculating the energy contribution per stage, respectively.

스크류원심펌프 임펠러 자오면형상 설계파라미터 최적화

Screw centrifugal pump is a non-clog type pump, which is widely used for drainage and sewage control systems. The screw centrifugal pump combines the advantages of the screw pump and centrifugal pump. Screw centrifugal pump shows the relatively high efficiency and the good solids handing capability. Based on a screw centrifugal pump design method, the parameters of impeller meridional plane shape are investigated for the improvement of pump performance. The design parameters of impeller meridional plane shape, such as impeller inlet and outlet diameters, outlet width, total axial length, blade inlet and outlet angles, and inclination angles, were investigated to examine their effects on the pump performance. Numerical analysis was conducted to determine the essential design variables for the screw centrifugal pump. Furthermore, flow passage shape optimization was conducted to enhance the performance of the screw centrifugal pump.

A comparative study on the reducing flow rate design method for a desalination energy recovery pump as turbine

The energy recovery and utilization of high-pressure brine are the key to reduce the cost. Reducing flow rate method (RFM) was put forward firstly to adapt pump as turbine (PAT) to a wide range of operating conditions in this paper. In order to validate advantages of the new method, three different designs of PAT were obtained, respectively, based on three different methods, which were, respectively, selection design method, forward curved method and RFM. Based on numerical method, the external energy characteristics, axial force and internal flow patterns of PATs were analyzed. Results show that matching of the blade inlet angle and flow angle at the blade leading edge has a great influence on the turbine flow patterns which are directly related to the efficiency of PAT. A PAT designed by the new design method RFM improves both the hydraulic efficiency and shaft power under design and partial load conditions. Moreover, the axial force of the PAT designed by RFM is reduced, which can improve the reliability of the PAT operation with high rotating speed.

Analisis Kinerja Pompa Sentrifugal pada Variasi Trim Diameter Menggunakan Simulasi Numerik

Diameter trimming is one of the most common modification on centrifugal pump impeller aimed to keep conformity between pump performance and required head and flow rate. In its application, centrifugal pump performance with trimmed diameter could be predicted by using affinity equations which based on geometrical similarity between pre- and post-trimming impeller. However, diameter trimming also alter the dimension ratio in blade passage which prompt further investigation on performance prediction of pump with trimmed impeller diameter. This research is carried out by using numerical simulation to analyze performance of pump with trimmed impeller diameter. The simulation is conducted on radial-type centrifugal pump with impeller diameter 105 mm, inlet blade angle 200, outlet blade angle 280, and operating on mass flow rate 1.5 kg/s at rotational speed 2800 rpm. RNG k-e model is used to model turbulence while trimmed diameter values are 100 mm and 95 mm. Results indicate that there is significant differences on head and consumed power between predicted value by simulation and predicted value obtained by employing affinity equations.

Research on the Flow Characteristic in a Multi-Stage Multiphase Pump by Numerical Simulations

As a cost-effective option for subsea gas and oil fields development, multiphase pump has been widely used and plays an important role in promoting field production especially for those brownfields. The objective of this research is to study the variations of flow parameters at the inlet of each stage in a five-stage helico-axial pump under design conditions by using commercial CFD packages. The numerical results show that inlet volume flow rate, gas volume fraction (GVF) and flow angle of each stage both decreases from the first stage to the fifth stage because of the compression. The variations of these parameters along the flow direction are susceptible to the effect of rotational speed and initial gas volume fraction at inlet of the first stage. These inlet flow parameters from inlet to outlet of the five-stage pump just change little when the initial inlet GVF is lower than 10% or higher than 90%. While the variation is obvious when inlet GVF is from 20% to 80%. Based on numerical simulation results, the stage-by-stage design method is proposed and geometry parameters such as inlet impeller hub diameter and inlet angle of blade in the second stage are modified according to its inlet flow conditions. The comparison results between the modified pump and original pump show that pressure distribution at leading edge of impeller blades in each stage becomes uniform in the modified multistage pump. The inlet incident flow loss of each stage is diminished and internal flow conditions has been significantly improved. Thus, the pump’s boosting capacity is enhanced. These research results in this paper are instructive for the performance optimization of multistage pumps used in gas oil fields.

Influence of Channel-Diffuser Blades on Energy Performance of a Three-Stage Centrifugal Pump

In order to improve hydraulic efficiency, influence of inlet angle, outlet angle, wrap angle, inlet shape and outer edge camber lines of channel-diffuser blades on the energy performance of a three-stage centrifugal pump were studied and the pressure distributions on the blade of the first-stage channel-diffuser were particularly analyzed. The result shows that the efficiency of the pump is maximal when the blade inlet angle is 12°. The pressure variation in the model with the inlet angle of 12° was small and the amplitude of fluctuation was also not large. When the outlet angle was 90°, the pressure distribution in the outlet of the blades that are symmetrically distributed along the center of the diffuser shell was significantly better than that with other outlet angles. The effect of the blade wrap angle of the channel-diffuser on the energy performance of the pump was relatively small. The internal flow in the diffuser with the diffusion inlet shapes was steady for both the convex surface and concave surface. The diffusion inlet of the channel-diffuser blade corresponded to the outlet region of the impeller blade, which reflected a good matching. The fluctuation amplitude and the distribution range of the models with a uniform transition were smaller than those with non-uniform transition. In order to verify the effectiveness of the research results, an experimental test was carried out on the pump. The results show that when the flow rate is 850 m3/h, the head of the pump is 138.67 m and the efficiency of pump is 69.48%.

Influence of blade inlet angle on the performance of a single blade centrifugal pump

Single blade centrifugal pump is suitable for transporting sewage water with large obstacles in diameter, which is required to achieve high performance. The blade inlet angle is a parameter that affects the performance of the single blade centrifugal pump. However, the selection of blade inlet angle is frequently based on experiences and demonstrates certain arbitrariness. Therefore, six impellers with different blade inlet angles are designed using ANSYS Bladegen and NX software. These impellers are categorized into Groups 1 and 2. The blade inlet angle of the impellers in Group1/Group2 increases/decreases from the front shroud to the rear one, respectively. Subsequently, the numerical simulation is carried out to investigate the effect of the blade inlet angle on the performance of the single blade pump. The blade inlet angle has more obvious influence on the head, efficiency, and shaft power for the impellers in Group 1 than those in Group 2. The lowest pressure is negative for one of the impellers in Group 1. Moreover, an optimum blade inlet angle improves the pump performance. In addition, the alternating load is small on the blades of the impellers in Group 2. The present results are helpful in designing the single blade centrifugal pump and improving its performance.

Optimization for a centrifugal pump transporting brine using orthogonal design based on CFD-DEM simulation

To enhance the reliability of a centrifugal pump transporting brine solutions with crystallization, the effect of impeller geometrical configurations on crystal particle behaviors was investigated by an orthogonal design based on CFD-DEM coupled method. In this work, the main impeller geometrical configurations were set as the blade inlet angle α1, blade outlet angle α2, wrap angle φ, and outlet width b2. In the meanwhile, the L9(34) orthogonal design containing 4 factors with 3 levels was applied in this study. Given the crystal particle features, CFD-DEM coupling method was utilized to study inner flow in a pump with crystal particles. Current results indicated that the blade outlet angle α2 could significantly affect the collisions between particles and blades. Moreover, a low-speed region at the blade pressure side in the optimal impeller has been reduced, declining the probability of the crystal particles adhering to the impeller.

Design and Performance Analysis of Mixed Flow Turbine Rotors With Extended Blade Chord

Abstract Mixed flow turbines offer additional design freedom compared with conventional radial turbines. This is useful in the automotive turbocharger application to reduce rotor inertia, which can be very beneficial for the transient response of a highly boosted downsized passenger car powertrain. A previously published study from the authors analyzed a series of nine mixed flow turbine rotors with varying blade cone angle and inlet blade angle. This paper reports an extension of that study with two further mixed flow turbine rotors where the chord length of the rotor blade was extended. The aim of this work was to understand both the aerodynamic and mechanical impacts of varying the chord length, particularly for the turbocharger application where off-design performance and transient response are very important. The baseline mixed flow rotor for this study had a blade cone angle of 30 deg and an inlet blade angle of 30 deg. Two further variations were produced; one with the trailing edge (TE) extended in the downstream direction across the entire blade span. In the second variation, the chord was extended at the hub corner only, while the shroud corner of the TE remained unchanged, with the aim of achieving some aerodynamic improvement while meeting mechanical requirements. When the blade was extended at both the hub and shroud, the inertia and stress levels increased significantly and the blade eigenfrequencies reduced. There was a significant improvement in peak efficiency, but the mechanical performance was unfavourable. The improvement in peak efficiency was mainly due to better exhaust diffuser performance and, therefore, would not be realized in most turbocharger installations. The blade that was extended at only the hub corner incurred very little additional inertia, and the centrifugal stresses and blade eigenfrequencies were improved. Consequently, it was possible to reduce the blade thickness at the TE in order to achieve a more aerodynamically optimized design. In this case, the mechanical performance was acceptable and there were efficiency improvements of up to 1.1% points at off-design conditions, with no reduction in peak efficiency or maximum mass flowrate. Therefore, the blade that was extended only at the hub produced some improvement within acceptable mechanical limits. The flow field features were considered for the three rotor geometries to explain the changes in loss and efficiency across the operating range.

Effect of Blade Coating on a Centrifugal Pump Operation under Sediment-Laden Water Flow

Applying a high strength coating on a blade’s surface could significantly prolong the service life of a centrifugal pump under sediment-laden water flow because of its protection. To explore the effect of blade coating, the characteristics of energy, vibration and pressure fluctuation of a centrifugal pump (the specific speed (ns) is 81.46) with different polyurethane coating thickness coefficients were experimentally studied under sediment-laden water flow. Keeping the blade outlet angle, blade inlet angle and blade shape unchanged, the head H and efficiency η under both sediment-laden flow and clear water flow decrease significantly as the coating thickness coefficient increases. The axis rotating frequency and blade passing frequency are the main excitation frequencies of the pump vibration velocity amplitude and outlet pressure fluctuation. The vibration velocity amplitude and outlet pressure fluctuation at the frequency of 1 BPF are the largest. At the frequency of 1 axis rotating frequency, they are the second in all cases. The peak values of both vibration velocity amplitude and outlet pressure fluctuation are proportional to the coating thickness coefficient. An analysis was performed for several increasing coating thicknesses, corresponding to coating coefficients from K0 to K3. When the coating thickness coefficients are K0, K1, and K2, the peak value of vibration velocity amplitude under sediment-laden flow is larger than that under clear water flow, but the very small difference between them undercoating thickness coefficient K3. The peak values of pressure fluctuations under different flow rates decrease first and then increase with the increasing coating thickness coefficient, and lowest points are all located at the coating thickness coefficient K1.