Inlet Box Structure Optimization of a Large Axial-Flow Fan Using Response Surface Methodology

2020 ◽  
Author(s):  
Jin Xiong ◽  
Yinkun Zhang ◽  
Penghua Guo ◽  
Jingyin Li
Keyword(s):  
Total Pressure ◽  
Design Method ◽  
Orthogonal Design ◽  
Axial Flow ◽  
Pressure Rise ◽  
Aerodynamic Performance ◽  
Design System ◽  
Orthogonal Design Method ◽  
Box Structure ◽  
Inlet Box

Abstract Large axial-flow fans are widely used in many fields. The inlet box is an integral part of large axial-flow fans, and a well-designed inlet box could effectively improve fan efficiency. However, the inlet box structure is complicated, and the existing inlet box design method severely depends on the design experience. In this study, we propose a structure optimization design system based on a surrogate model technique for researching the critical structure parameters of the inlet box and accomplishing aerodynamic performance optimization. As for this expensive optimization problem, the design system contains twice optimization procedures by using the Response Surface Methodology (RSM) with the orthogonal design method. The optimization object is an existing large axial-flow fan. The optimization objective is the total pressure efficiency of the fan, and the total pressure rise is the restriction condition. We generate eighteen different inlet boxes connect with the same impeller and outlet pipe by the orthogonal design method and calculated fan aerodynamic performance by CFX software. After the first optimization, we find the key structural parameters by the sensitivity analysis and the reselect variables total of 25 cases are adopted in a further RSM optimal process. The ultimate surrogate model estimates the fan with the optimal inlet box has a better aerodynamic characteristic and a 6.7% total pressure efficiency rise. Finally, we compare the aerodynamic characteristics of the ultimate design fan and the initial fan by CFD simulation. The numerical results show that: the total pressure efficiency is 6.5% higher than that of the initial impeller, and the pressure rise is 3% higher than that of the initial impeller. The result demonstrates that some most critical parameters of the inlet box structure decide the aerodynamic performance, and the inlet box optimization effectively increases the fan efficiency in the meanwhile.

Computation and Measurement of the Flow in Axial Flow Fans With Skewed Blades

1999 ◽  
Vol 121 (1) ◽  
pp. 59-66 ◽  
Author(s):  
M. G. Beiler ◽  
T. H. Carolus
Keyword(s):  
Total Pressure ◽  
Design Method ◽  
Power Level ◽  
Three Dimensional ◽  
Axial Flow ◽  
Pressure Rise ◽  
Fast Response ◽  
Test Facility ◽  
Navier Stokes ◽  
Pressure Probe

A numerical analysis of the flow in axial flow fans with skewed blades has been conducted to study the three-dimensional flow phenomena pertaining to this type of blade shape. The particular fans have a low pressure rise and are designed without stator. Initial studies focused on blades skewed in the circumferential direction, followed by investigations of blades swept in the direction of the blade chord. A Navier–Stokes code was used to investigate the flow. The simulation results of several fans were validated experimentally. The three-dimensional velocity field was measured in the fixed frame of reference with a triple sensor hot-film probe. Total pressure distribution measurements were performed with a fast response total pressure probe. The results were analyzed, leading to a design method for fans with swept blades. Forward swept fans designed accordingly exhibited good aerodynamic performance. The sound power level, measured on an acoustic fan test facility, improved.

The Study on Solid Superacid Synthesis of K12A with Manufacturing Equipment

2012 ◽  
Vol 583 ◽  
pp. 285-288
Author(s):  
Dong Mei Zhao ◽  
Xue Peng Liu
Keyword(s):  
Catalytic Activity ◽  
Metal Oxide ◽  
Design Method ◽  
Orthogonal Design ◽  
Manufacturing Equipment ◽  
Solid Superacid ◽  
Orthogonal Design Method ◽  
Superacid Catalyst ◽  
Calcined Temperature ◽  
Very High

By orthogonal design method, Catalytic activity of /ZrO2 solid superacid is studied, and the influence of catalyst characteristic and structure by manufacturing equipment is issued. It is concluded that the best prepared conditions of the superacid catalyst /ZrO2 for the synthesis of Octyl-Polyglycoside are followed:(1) PH=9.5; (2) calcined temperature at 500; (3) M(H2SO4)=0.5mol/L. Using this kind of catalyst the conversion of glueoside may reach as high as 96% in the synthesis of OCtyl-Polyglycoside and the selectivity is very high for the synthesis of Octyl-Polyglycoside. By introducing other metal oxide, the catalytic activity of complex solid superacid is studied.

Aerodynamics of Contra-Rotating Fans With Swept Blades

2015 ◽  
Author(s):  
K. Vijayraj ◽  
M. Govardhan
Keyword(s):  
Rotational Speed ◽  
Axial Flow ◽  
Pressure Rise ◽  
Aerodynamic Performance ◽  
The Other ◽  
Flow Structures ◽  
Current Investigation ◽  
Rotating System ◽  
Stall Margin ◽  
Static Head

A Counter-Rotating System (CRS) is composed of a front rotor and a rear rotor which rotates in the opposite direction. Compared with traditional rotor-stator system, the rear rotor is used not only to recover the static head but also to supply energy to the fluid. Therefore, to achieve the same performance, the use of a CRS may lead to a reduction of the rotational speed and may generate better homogeneous flow downstream of the stage. On the other hand, the mixing area in between the two rotors induces complicated interacting flow structures. Blade sweep has attracted the turbomachinery blade designers owing to a variety of performance benefits it offers. However, the effect of blade sweep on the performance, stall margin improvements whether it is advantageous/disadvantageous to sweep one or both rotors has not been studied till now. In the current investigation blade sweep on the performance characteristics of contra rotating axial flow fans are studied. Two sweep schemes (axial sweeping and tip chord line sweeping) are studied for two sweep angles (20° and 30°). Effect of blade sweep on front rotor and rear rotor are dealt separately by sweeping one at a time. Both rotors are swept together and effect of such sweep scheme on the aerodynamic performance of the stage is also reported here. The performance of contra rotating fan is significantly affected by all these parameters. Blade sweep improved the pressure rise and stall margin of front rotors. Axially swept rotors are found to have higher pressure rise with reduced incidence losses near the tip for front rotors. Sweeping the rear rotor is not effective since the pressure rise is less than that of unswept rotor and also has less stall margin.

Development of a New Design Method for High Efficiency Swept Low Pressure Axial Fans With Small Hub/Tip Ratio

2014 ◽  
Author(s):  
Thore Bastian Lindemann ◽  
Jens Friedrichs ◽  
Udo Stark
Keyword(s):  
High Efficiency ◽  
Design Method ◽  
Tangential Velocity ◽  
Pressure Rise ◽  
Low Pressure ◽  
Aerodynamic Performance ◽  
Low Noise ◽  
Angle Distribution ◽  
Sweep Angle ◽  
Reduced Pressure

For a competitive low pressure axial fan design low noise emission is as important as high efficiency. In this paper a new design method for low pressure fans with a small hub to tip ratio including blade sweep is introduced and discussed based on experimental investigations. Basis is an empirical axial and tangential velocity distribution at the rotor outlet combined with a distinctive sweep angle distribution along the stacking line. Several fans were designed, built and tested in order to analyze the aerodynamic as well as the aeroacoustic behavior. For the aerodynamic performance particular attention was paid to compensate the influence of reduced pressure rise and efficiency due to increasing blade sweep. This was achieved by a method of increasing the blade chord depending on the local sweep angle which is based on single airfoil data. The tested fans without this compensation revealed a significant noise reduction effect of up to approx. 6 dB(A) for a tip sweep angle of 64° which was accompanied by an unsatisfactory effect of reduced overall aerodynamic performance. The second group of fans did not only confirm the method of the aerodynamic compensation by a nearly unchanged pressure rise and efficiency characteristic but also revealed an increased aeroacoustic benefit of in average 9.5 dB(A) compared to the unswept version. Beside the overall characteristics the individual differences between the designs are also discussed using results of wall pressure measurements which show some significant changes of the blade tip flow structure.

scholarly journals Optimization of Evodiamine-Imprinted Composite Membrane by Orthogonal Design Method

2013 ◽  
Vol 25 (18) ◽  
pp. 10425-10430
Author(s):  
Huiling Cheng ◽  
Guangyan He ◽  
Xiufang Zhu ◽  
Hao Zhou ◽  
Mingfeng Wang ◽  
...  
Keyword(s):  
Composite Membrane ◽  
Design Method ◽  
Orthogonal Design ◽  
Orthogonal Design Method

The Research of the Lime Soil Properties on the Road in Jilin Area

2012 ◽  
Vol 446-449 ◽  
pp. 2478-2481
Author(s):  
Dong Guo Li ◽  
Gui Mei Shi
Keyword(s):  
Design Method ◽  
Orthogonal Design ◽  
General Rule ◽  
Effect Factor ◽  
The Road ◽  
Orthogonal Design Method ◽  
Region Difference ◽  
Stabilized Soil ◽  
On The Road ◽  
Special Region

Lime soil, literature [1] just gave a general rule to the mixture’s composition design. Because of the soil’s ingredient region difference, the reasonable mix of lime soil in special region must be determined by the test. This paper first quoted the formation of lime soil’s strength and the effect factor, and then regarded the non-side limitation compressive strength at different ages as inspection norm. Used orthogonal design method, the mix for the lime stabilized soil in Jilin area was investigated in this paper. The optimum mix and the main effect factor was determined by the strength at 28 days and verified by the regression strength at 90 days. In the meantime, the key problem had been summarized on the lime stabilized soil construction point and quality control.

scholarly journals Orthogonal Design Method for Optimizing Roughly Designed Antenna

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Qing Zhang ◽  
Sanyou Zeng ◽  
Chunbang Wu
Keyword(s):  
Design Method ◽  
Orthogonal Design ◽  
Simulation Software ◽  
Specific Region ◽  
Antenna Design ◽  
Wire Antenna ◽  
Real World Application ◽  
Orthogonal Design Method ◽  
Numerical Electromagnetics ◽  
Geometrical Factors

Orthogonal design method (ODM) is widely used in real world application while it is not used for antenna design yet. It is employed to optimize roughly designed antenna in this paper. The geometrical factors of the antenna are relaxed within specific region and each factor is divided into some levels, and the performance of the antenna is constructed as objective. Then the ODM samples small number of antennas over the relaxed space and finds a prospective antenna. In an experiment of designing ST5 satellite miniantenna, we first get a roughly evolved antenna. The reason why we evolve roughly is because the evolving is time consuming even if numerical electromagnetics code 2 (NEC2) is employed (NEC2 source code is openly available and is fast in wire antenna simulation but not much feasible). Then the ODM method is employed to locally optimize the antenna with HFSS (HFSS is a commercial and feasible electromagnetics simulation software). The result shows the ODM optimizes successfully the roughly evolved antenna.

Preparation and Sintering Behavior of Au Conductor Pastes for LTCC Substrate

2005 ◽  
Vol 475-479 ◽  
pp. 1763-1766 ◽  
Author(s):  
Yan Wang ◽  
Yang Liu ◽  
Ju Sheng Ma ◽  
Zhaowen Dong ◽  
Mingli Yin
Keyword(s):  
Electrical Conductivity ◽  
Particle Size ◽  
Design Method ◽  
Orthogonal Design ◽  
Average Particle Size ◽  
Sintering Behavior ◽  
Average Particle ◽  
High Electrical Conductivity ◽  
Orthogonal Design Method ◽  
Ltcc Substrate

Fine Au powders with spherical morphology and good dispersivity were produced. The average particle size is 1~2m. The influences of constituents on the rheology of organic vehicles were investigated by orthogonal design method. Consequently, the compatible Au thick film pastes for LTCC substrate have been prepared. SEM was carried out to study the sintering behaviors and microstructures of the buried pastes with LTCC substrate. These pastes have high electrical conductivity (less than 3m/sq.), reliable wire bond strength (greater than 9 grams, 25m Au wire) and fine line printability (as small as 80m). The via filling technology was also discussed in this paper.

scholarly journals Surface Roughness Prediction Model for Machining O1 Die Steel Through EDM

2019 ◽  
Vol 4 (2) ◽  
Author(s):  
Jai Prakash ◽  
Ashish Agarwal ◽  
Vipin
Keyword(s):  
Mathematical Model ◽  
Surface Roughness ◽  
Current Pulse ◽  
Process Parameters ◽  
Design Method ◽  
Orthogonal Design ◽  
Die Steel ◽  
Orthogonal Design Method ◽  
Roughness Prediction ◽  
Taguchi Orthogonal Design

The objective of this paper is to generate a mathematical model in order to minimize the value of surface roughness (Ra) through EDM by constructing an objective function consisting of combination of process parameters. Taguchi orthogonal design method of experiments with three process parameters viz., current, pulse-on-rate, pulse-off-rate were used to generate 25 numbers of experiments L25 at five levels. Experiments were carried out in Electronica S50 (CNC) EDM. Data obtained for performance measurement was subjected regression analysis using ANOVA. Equation was obtained for the surface roughness as a function of current, pulse-on rate, pulse-off-rate.It is found that discharge current, pulse-on-rate, and pulse-off-rate have significant effect on the Ra. Higher values of current and pulse-on-rate increased surface roughness. Lower current, lower pulse-on-rate and relatively higher pulse-off-rate produced a better surface finish.

Sign in / Sign up

Export Citation Format

Share Document