• 대한기계학회논문집B
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• 제35권10호
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• pp.1067-1073
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• 2011

본 연구에서는 생활폐기물 관로이송 설비에 사용되고 있는 원심송풍기의 성능향상을 위해 임펠러날개 압력면과 부압면 측에 스플리터를 각각 설치하고, 스플리터의 코드길이 변화에 따른 성능특성을 삼차원 나비어-스톡스 방정식을 이용한 수치해석으로 분석하였다. 수치해석을 통한 기초연구를 바탕으로 날개 부압면측에서 발생하는 역류현상을 억제할 수 있는 스플리터의 익간설치를 고려하였으며, 주요설계 변수로는 코드길이를 설정하였다. 이를 통해 날개 부압면 측에 설치한 스플리터의 코드길이가 길어질수록 원심송풍기 압력 및 효율특성이 설계유량 조건 뿐만 아니라 유량증가에 따라 향상됨을 알수 있었다. 설계유량 조건에서 스플리터 부착 원심송풍기에 의해 효율 및 압력은 기존대비 각각 4% 및 18% 향상되었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.75.1-75.1
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• 2005

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.381-385
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• 2009

This paper describes performance characteristics of a centrifugal fan having a different volute casing. The centrifugal fan has a backward blade type, and is used in a refuse collecting system. The flow characteristics inside the components are analyzed by three-dimensional Navier-Stokes analysis, and also compared to the results by experiments. Distributions of pressure and efficiency obtained by numerical simulation has a good agreement with the experimental results. Throughout the numerical simulation of the centrifugal fan, a fan efficiency is increased by decreasing local losses in the blade passage. It is found that the fan efficiency is enhanced by decreasing the distance between the shroud of a impeller and casing. Detailed flow analysis is also analyzed and discussed using the results obtained by numerical simulation.

• 대한기계학회논문집
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• 제16권5호
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• pp.999-1003
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• 1992

본 연구에서는 Fig.1에 보인 바와 같이 원심휀이 부착된 실내 에어콘을 대상 으로 하여 원심휀의 진동.소음 특성을 연구하였다. Fig.2에서 보인바와 같이 원심휀 은 전기 모터 축에 커플링 되어 있으며 원심휀의 회전으로 발생된 공기유동은 연결된 덕트 시스템(duct system)을 통해 외부로 방출 된다. 이와 같은 송풍시스템에서 발 생하는 진동.소음은 크게 구조물 진동에 의한 구조물진동소음과 공기유동 자체에서 발 생하는 공기유동소음으로 구별된다. 본 연구는 실험적 연구를 통하여 이들 진동. 소 음원의 주파수 특성과 전체 소음에의 기여도 등을 규명하였다.

• 한국전산유체공학회지
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• 제9권1호
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• pp.10-17
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• 2004

Comprehensive investigation according to the two kinds of blades is systematically carried out for a design of the centrifugal blower. The motivation of this work is due to demand of enhanced flow rate with higher inlet pressure, such as air purifiers adopting several filters. It is observed that flow rate of the blower with forward blades is larger than that of the system with backward blades. The reason is due to larger outlet velocity from the rotating forward blades and the tendency is validated by a parallel experiment with a wind tunnel. Numerical analysis for the blower system shows detail information between the blades and inside the casing. A series of figures to show the flow details offers deep understanding of a centrifugal blower with the two different blades.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2004년도 유체기계 연구개발 발표회 논문집
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• pp.70-77
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• 2004

Comprehensive investigation on the outlet's geometric shapes of a centrifugal blower with higher inlet resistance than an atmospheric pressure is carried out for improvements of its performance. Most unwanted behaviors of such blower are pulsating flows because of unbalance between inflows and outflows in a scroll casing. In order to reduce this undesirable phenomenon a triump is made for both the shape of outlet duct and an accessory structure inserted in the outlet port of the blower. The modification on the shape is concerned with the contraction of cross sectional area and the attached structure is for an intentional obstruction to cause a flow resistance. The details of the modification are examined for different cases and results. The methodologies for the work are performance evaluations including noise level and velocity measurements with PIV Consequently, the performance of improved system is close to that of the system operating with atmospheric pressure at the inlet.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2003년도 추계 학술대회논문집
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• pp.165-170
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• 2003

Centrifugal blowers are widely used for air handling units in industry applications. The blower has a centrifugal impeller and a scroll casing including a driving component such as an electric motor. The impeller takes forward or backward blades to induce flows into the blower. Comprehensive investigation according to the two kinds of blades is systematically carried out for a guidance of design. It is observed that flow rate of the blower with forward blades is larger than that of the system with backward blades. The reason is due to larger velocity from the rotating forward blades and the tendency is validated by a parallel experiment with a wind tunnel. Numerical analysis for the system shows detail information inside the blades and the casing. A series of figures to show the flow details offers deep understanding of a centrifugal blower with different blades.

• 한국소음진동공학회논문집
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• 제21권8호
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• pp.726-732
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• 2011

Straight absorptive silencers have been designed to reduce the noise level of a centrifugal blower. Three-dimensional boundary element method is used for the design of absorptive silencers which consist of a perforated main pipe and a outer chamber filled with fibrous material. The experimental results show that the absorptive silencer reduces up to 8 dB(A) in the overall sound pressure level of the blower and up to 15 dB at the blade passing frequency. It is also found that the gap between the silencer and the impeller may substantially alter the acoustic performance of the silencers. The transmission loss predicted by the boundary element method follows overall trends of the measured insertion loss. The experiments also show that the impact of the silencers on the aerodynamic performance of the blower is minimum.

• 한국수소및신에너지학회논문집
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• 제25권2호
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• pp.191-199
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• 2014

Effects of design variables on the performance of a double-inlet centrifugal blower have been analyzed based on the three-dimensional flow analysis. Two design variables, blade inlet and outlet angles, are introduced to enhance a blower performance. General analysis code, ANSYS-CFX13, is employed to analyze internal flow and a blower performance. SST turbulence model is employed to estimate the eddy viscosity. Throughout the shape optimization of an impeller at the design flow condition, the blower efficiency and pressure are successfully increased by 4.7 and 1.02 percent compared to reference one. It is noted that separated flow observed near cut-off region can be reduced by optimal design of blade angles, which results in stable flow pattern in the blade passage and increase of a blower performance. The stable flow at the impeller also makes good effects at the outlet of a volute casing.

• 한국유체기계학회 논문집
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• 제17권1호
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• pp.28-34
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• 2014

This paper presents the performance enhancement of a double-inlet centrifugal blower by the shape optimization of an impeller. Two design variables, a number of blade and a length of chord, are introduced, and analyzed by a response surface method. Three-dimensional compressible Navier-Stokes equations are used to analyze the blower performance and the internal flow of the blower. Throughout the numerical simulation of the blower, blower efficiency can be increased by reducing separation flow generating from the blade leading edge of a blade pressure surface. It is noted that recirculation flow observed inside the blade passage induces low velocity region, thus increases pressure loss. Efficiency and pressure of the optimum blower are successfully increased up to 3% and 3.9% compared to those of reference blower at the design flow condition, respectively. Detailed flow field inside the blower is also analyzed and compared.