SOUND POWER LEVELS OF A 36'' DIAMETER PLUG FAN.
Lilly, Jerry G. ; Towne, Robin M.(Towne, Richards & Chaudiere Inc,, Seattle, WA, USA, Towne, Richards & Chaudiere Inc, Seattle, WA, USA); Towne, Robin M. Source: Proceedings - National Conference on Noise Control Engineering, p 285-292, 1983The sound power levels of a 36'' diameter plug fan have been determined by direct measurement in accordance with AMCA 300-67. The resulting sound power levels are considerably less than those for conventional scroll centrifugal fans operating at the same duty point. The lower sound power levels and the vertical configuration make this unit ideally suited for typical floor by floor air handling units in high rise office buildings. An example has been presented which illustrates that a system of this type can be installed adjacent to an open office area without the use of conventional sound traps or masonry partitions and still achieve acceptable noise levels. 直径为36的无蜗壳离心风机的声功率级
直径为36的无蜗壳离心风机的声功率级按照AMCA 300-67的标准进行了直接测量。结果表明，在同一工作点时，无蜗壳离心风机的声功率级远远低于传统的涡旋离心风机。较低的声功率水平和垂直配置，使无蜗壳离心风机非常适合于高层办公楼典型的一层层的空气处理机组。且举例说明这种类型的系统可以安装在一个开放的办公区附近，无需使用传统的隔音设备或砌体隔墙，仍使噪音达到可接受的水平。 Unhoused (plug/plenum) fans: Is their performance predictable?
Coward Jr., Charles W. 1 (Waddell Engineering Co, Morristown, United States) Source: ASHRAE Journal, v 39, n 10, Oct 1997 11
Plug /plenum fans have had a generally successful past and should have an equally successful future. The performance of a plug fan can be as predictable as the performance of a housed fan , but the engineering analysis must be thorough and good traceable data should be used. Computer modeling of the aerodynamic performance of the unhoused fan will help to minimize future performance problems. Other interesting investigations might include computational fluid dynamics (CFD) modeling of temperature and velocity contours in the discharge plenum or possibly optimizing plenum designs.
无蜗壳离心风机的性能可预测吗？
无蜗壳离心风机总的来说在过去是很成功的，同样也应该有一个成功的未来。无蜗壳离心风机的性能如蜗壳离心风机一样是能被预测的，但必须通过工程分析，并使用良好的可追踪的数据。无涡壳风机空气动力学性能的计算机建模将有助于减少未来的性能问题。其它有趣的研究包括使用计算流体动力学（CFD ）方法数值模拟排气室内的温度和速度等值线来优化通风设计。
Experimental investigation to determine the influence of an air-handling unit on the characteristics and acoustics of plug centrifugal fans
Sadi, O.1; Kremer, P.Sadi, O. (Development Department, Ziehl-Abegg, Germany); Kremer, P . Source: IMechE Event Publications , v 2004 4, p 169-178, 2004, International Conference on FANS - IMechE Conference Transactions
The object of this investigation is the influence of a air handling unit box on the characteristics and acoustics of so-called free-wheeling centrifugal fans (figure 1). Air handling unit boxes are used for the air-conditioning of buildings, conference centres etc. The new high-performance C impeller from Ziehl-Abegg is tested in a air handling unit test section. The measurement of the fan performance and acoustics is done in cooperation with the University of Heilbronn. The prototype and the test sections will be described by using pictures and drawings. To visualize the
flow conditions at the outlet of the impeller, we used a so-called thread probe. The pictures were taken using a high-speed CCD camera. With the so-called PIV method (Particle Image V elocimetry), the flow speed in the outlet area of the impeller is measured. This measurement is done in cooperation with the company Dantec Ltd. The results of these experimental investigations are used to improve the C impeller and to define an algorithm to calculate the influence of the air handling unit on the fan characteristics. This algorithm is implemented in a fan selection program. Company Ziehl-Abegg 2004.
确定空气处理机组对无蜗壳离心风机的性能和声音影响的实验研究
本文研究的是空气处理机组对无蜗壳离心风机的性能和声音的影响。空气处理机组常用于建筑物空调和会议中心等。Ziehl-Abegg 风机的新高性能C 叶轮经过空气处理单元测试段进行测试。与海尔布隆大学合作完成了风机性能和声音的测量。使用照片和图纸来描述原型和测试部分。我们使用线型探针使叶轮出口的流动可视化。并使用高速摄像机来拍摄照片，结合粒子图像测速方法，测量叶轮出口处的流速。与丹迪公司合作完成该测量。实验研究结果将用于改善C 叶轮以及定义计算空气处理机组对风机性能影响的算法。该算法可用于实现风机选型。
Numerical simulation pressure drop through a rotating plenum fan
Borg, John P . (Marquette University, Dept. of Mechanical Engineering, Haggerty Engineering Building, 1515 W. Wisconsin, Milwaukee, WI 53233) Source: Proceedings of the ASME Power Conference, 2005, v PART A, p 95-100, 2005, Proceedings of the ASME Power Conference, 2005: Includes Papers from the 2005 International Conference on Power Engineering, ICOPE In this paper the numerically determined pressure increase (AP) versus volumetric flow rate (CFM) curve at a given fan speed for a plenum fan is compared to experimental data. The simulations were carried out using a rotating fan blade section and a fixed inlet and outlet plenum with a three-dimensional tetrahedral computational mesh. The objective of this work is to assess the feasibility of approximating a 36" plenum AP-CFM fan curve using a low order computational approach and thereby assessing the effectiveness of using such an approach as a real time design tool. The measures of success of this work include demonstrating the ability to capture pertinent characteristics of the fan curve such as slope and roll-off of the ΔP-CFM curve. It was found that a fairly high resolution was required near the fan blade section in order to better approximate the Δ-CFM curve. This higher resolution greatly increased the runtime. In addition, including a k-e turbulent model improved the pressure drop characteristics as compared having no turbulence model. It is hoped that an approach such as this will be adopted in the real time design and manufacture of plenum fans . Copyright 2005 by ASME
转动的无蜗壳离心风机压降的数值模拟
本文的数值确定了给定无蜗壳离心风机的转速时，压力增加（AP 大气压）与体积流量（立方英尺CFM ）的曲线，并与实验数据进行了对比。对旋转风机叶片部分和固定的进出口，采用三维四面体计算网格进行了数值模拟。本研究的目的是使用低阶的计算方法来评估36" 左右的无蜗壳风机AP-CFM 曲线的可行性，从而评估使用这种方法作为实时设计工具的有效性。本研究取得成功的措施包括展示了捕捉风机曲线的相关特性，如斜率和下降的 ΔP-CFM 曲线的能力。研究发现，风机叶片部分需要较高的分辨率以更好地近似Δ-CFM 曲线。这种高分辨率大大增加了运行时间。此外，与没有湍流模型相比，κ-ε湍流模型改善了压降的特性。希望这样的方法能用于无蜗壳离心风机的实时设计和制造中。
Maximum Achievable Efficiency of Centrifugal Fans Without Housing 1
XIA Yingan
The present paper is focused on centrifugal fan wheels with backward curved blades and a rotating diffuser in free-blowing operating (without housing). Moreover, the consideration is confined to the flow area within impeller.
Such centrifugal fans are very popular for the use in air handling units because of advantages such as compact design and direct drive etc.. The fan efficiency ηr is, however, a little lower than the fan with housing, which converts the dynamic flow energy of the air directly into usable static flow energy. There is no doubt a further potential to improve the efficiency through a further aerodynamic optimization of the wheel geometry. It is, however, exciting to know on which pa rameters the efficiency of these fans ηr primarily depends and what is the theoretic limit of the efficiency maximum achievable ηr,max.
The basis for the theoretic consideration is the Euler's main equation, which describes the energy conversion in the fan wheel. For an idealized flow within the fan wheel the relation between the fan efficiency ηr and the hydraulic efficiency of the blading (incl. inflow and outflow from the wheel) ηhydr is derived in function of the other technical operating and geometric parameters.
A theoretic estimation of the expected efficiency ηr of an aerodynamically "lossfree" fan can be carried out by ηhydr = 1. Inversely from the really measured/achieved efficiency ηr of a fan, the theoretic, hydraulic efficiency ηhydr can then be estimated as to the introduced formula aiming at evaluating the potential for a realistic improvement.
Three wheel examples with different blade geometries show how much the efficiency of a fan without housing depends on the working point (air volume and pressure) apart from the blade geometry. The limit of the maximum efficiency achievable of a centrifugal fan should in fact be higher than the real value of 73% presently achieved at the working point with a dimensionless volume number: 0.26 and a dimensionless pressure number: 0.57. The margin for a further improvement through an aerodynamic optimization of the flow in the wheel should, however, be highly limited for this wheel due to the high value already achieved.
In order to increase the total efficiency of the fan, the efficiency of other components like motor, control, etc. has to be improved as well
无蜗壳离心风机可实现的最大效率
本文的重点是离心风机轮向后弯曲的叶轮和自由进风的旋转扩散器（无蜗壳）。此外，考虑的仅限于叶轮内的流通区域。
这种离心风机在空气处理机组应用广泛，是因为具有设计紧凑和直接驱动等优点。但是，该风机效率ηr略低于有蜗壳离心风机，它将空气的动能直接转化为可用的静能。毫无疑问的是通过优化叶轮的几何来进一步提高潜在的效率。令人兴奋的是知道了这类风机的效率ηr主要依赖于哪些参数，及可实现的最大效率的理论极限。
理论考虑的基础是欧拉方程，它描述了风机叶轮中的能量转换。对风机叶轮内的理想化流动，风机效率ηr和叶片（包括叶轮的进出口）的水力效率ηhydr的关系由其它技术操作和几何参数推导出。
理论估计预期的“无损”风机的空气动力学效率ηhydr= 1。它与实测的风机效率ηr成反比，理论上，水力效率ηhydr可以被引入用于评估实际的改进可能性的公式。
不同叶片几何的三种叶轮实例表明无蜗壳离心风机的效率除取决于叶片的几何形状外，还取决于工作点（风量和压力）。离心风机可利用的最大效率实际上高于现在在工作点（无量纲的风量为0.26，无量纲的压力为0.57）能达到的73%的真实值。然而，通过叶轮的空气动力学优化得到的改善是很有限的，因为该叶轮目前达到的值已经很高。
为了增加风机的总效率，和其他部件，像电机、控制器等的效率，还需要做进一步的改善。
Lilly 等人对直径为36的无蜗壳离心风机的声功率级按照AMCA 300-67的标准进行了直接测量。结果表明，在同一工作点时，无蜗壳离心风机的声功率级远远低于传统的涡旋离心风机。较低的声功率水平和垂直配置，使无蜗壳离心风机非常适合于高层办公楼典型的一层层的空气处理机组。并举例说明这种类型的系统可以安装在一个开放的办公区附近，无需使用传统的隔音设备或砌体隔墙，仍使噪音达到可接受的水平。
1
Coward 等人认为无蜗壳离心风机的性能如蜗壳离心风机一样是能被预测的，但必须通过工程分析，并使用良好的可追踪的数据。无涡壳风机空气动力学性能的计算机建模将有助于减少未来的性能问题。并且可以使用计算流体动力学（CFD ）方法数值模拟排气室内的温度和速度等值线来优化通风设计。 1
Sadi 等人研究了空气处理机组对无蜗壳离心风机的性能和声音的影响。Ziehl-Abegg 风机的新高性能C 叶轮经过空气处理机组测试段进行测试，使用照片和图纸来描述原型和测试部分。此外使用线型探针使叶轮出口的流动可视化，并使用高速摄像机来拍摄照片，结合粒子图像测速方法，测量叶轮出口处的流速。实验研究结果将用于改善C 叶轮以及定义计算空气处理机组对风机性能影响的算法。 2
Borg 数值确定了给定无蜗壳离心风机的转速时，压力增加（AP 大气压）与体积流量（立方英尺CFM ）的曲线，并与实验数据进行了对比。其目的是使用低阶的计算方法来评估36" 左右的无蜗壳风机AP-CFM 曲线的可行性，从而评估使用这种方法作为实时设计工具的有效性。研究发现，风机叶片部分需要较高的分辨率以更好地近似Δ-CFM 曲线，但高分辨率大大增加了运行时间。此外，与没有湍流模型相比，κ-ε湍流模型改善了压降的特性。 2
XIA Yingan 等人研究了无蜗壳离心风机轮向后弯曲的叶轮和自由进风的旋转扩散器，仅限于叶轮内的流通区域。得出结论：无蜗壳离心风机的效率ηr略低于有蜗壳离心风机，它将空气的动能直接转化为可用的静能，可以通过优化叶轮的几何来进一步提高它的潜在的效率。不同叶片几何的三种叶轮实例表明无蜗壳离心风机的效率除取决于叶片的几何形状外，还取决于工作点（风量和压力）。离心风机可利用的最大效率实际上高于现在在工作点（无量纲的风量为0.26，无量纲的压力为0.57）能达到的73%的真实值。然而，通过叶轮的空气动力学优化得到的改善是很有限的，因为该叶轮目前达到的值已经很高。
2
SOUND POWER LEVELS OF A 36'' DIAMETER PLUG FAN.
Lilly, Jerry G. ; Towne, Robin M.(Towne, Richards & Chaudiere Inc,, Seattle, WA, USA, Towne, Richards & Chaudiere Inc, Seattle, WA, USA); Towne, Robin M. Source: Proceedings - National Conference on Noise Control Engineering, p 285-292, 1983The sound power levels of a 36'' diameter plug fan have been determined by direct measurement in accordance with AMCA 300-67. The resulting sound power levels are considerably less than those for conventional scroll centrifugal fans operating at the same duty point. The lower sound power levels and the vertical configuration make this unit ideally suited for typical floor by floor air handling units in high rise office buildings. An example has been presented which illustrates that a system of this type can be installed adjacent to an open office area without the use of conventional sound traps or masonry partitions and still achieve acceptable noise levels. 直径为36的无蜗壳离心风机的声功率级
直径为36的无蜗壳离心风机的声功率级按照AMCA 300-67的标准进行了直接测量。结果表明，在同一工作点时，无蜗壳离心风机的声功率级远远低于传统的涡旋离心风机。较低的声功率水平和垂直配置，使无蜗壳离心风机非常适合于高层办公楼典型的一层层的空气处理机组。且举例说明这种类型的系统可以安装在一个开放的办公区附近，无需使用传统的隔音设备或砌体隔墙，仍使噪音达到可接受的水平。 Unhoused (plug/plenum) fans: Is their performance predictable?
Coward Jr., Charles W. 1 (Waddell Engineering Co, Morristown, United States) Source: ASHRAE Journal, v 39, n 10, Oct 1997 11
Plug /plenum fans have had a generally successful past and should have an equally successful future. The performance of a plug fan can be as predictable as the performance of a housed fan , but the engineering analysis must be thorough and good traceable data should be used. Computer modeling of the aerodynamic performance of the unhoused fan will help to minimize future performance problems. Other interesting investigations might include computational fluid dynamics (CFD) modeling of temperature and velocity contours in the discharge plenum or possibly optimizing plenum designs.
无蜗壳离心风机的性能可预测吗？
无蜗壳离心风机总的来说在过去是很成功的，同样也应该有一个成功的未来。无蜗壳离心风机的性能如蜗壳离心风机一样是能被预测的，但必须通过工程分析，并使用良好的可追踪的数据。无涡壳风机空气动力学性能的计算机建模将有助于减少未来的性能问题。其它有趣的研究包括使用计算流体动力学（CFD ）方法数值模拟排气室内的温度和速度等值线来优化通风设计。
Experimental investigation to determine the influence of an air-handling unit on the characteristics and acoustics of plug centrifugal fans
Sadi, O.1; Kremer, P.Sadi, O. (Development Department, Ziehl-Abegg, Germany); Kremer, P . Source: IMechE Event Publications , v 2004 4, p 169-178, 2004, International Conference on FANS - IMechE Conference Transactions
The object of this investigation is the influence of a air handling unit box on the characteristics and acoustics of so-called free-wheeling centrifugal fans (figure 1). Air handling unit boxes are used for the air-conditioning of buildings, conference centres etc. The new high-performance C impeller from Ziehl-Abegg is tested in a air handling unit test section. The measurement of the fan performance and acoustics is done in cooperation with the University of Heilbronn. The prototype and the test sections will be described by using pictures and drawings. To visualize the
flow conditions at the outlet of the impeller, we used a so-called thread probe. The pictures were taken using a high-speed CCD camera. With the so-called PIV method (Particle Image V elocimetry), the flow speed in the outlet area of the impeller is measured. This measurement is done in cooperation with the company Dantec Ltd. The results of these experimental investigations are used to improve the C impeller and to define an algorithm to calculate the influence of the air handling unit on the fan characteristics. This algorithm is implemented in a fan selection program. Company Ziehl-Abegg 2004.
确定空气处理机组对无蜗壳离心风机的性能和声音影响的实验研究
本文研究的是空气处理机组对无蜗壳离心风机的性能和声音的影响。空气处理机组常用于建筑物空调和会议中心等。Ziehl-Abegg 风机的新高性能C 叶轮经过空气处理单元测试段进行测试。与海尔布隆大学合作完成了风机性能和声音的测量。使用照片和图纸来描述原型和测试部分。我们使用线型探针使叶轮出口的流动可视化。并使用高速摄像机来拍摄照片，结合粒子图像测速方法，测量叶轮出口处的流速。与丹迪公司合作完成该测量。实验研究结果将用于改善C 叶轮以及定义计算空气处理机组对风机性能影响的算法。该算法可用于实现风机选型。
Numerical simulation pressure drop through a rotating plenum fan
Borg, John P . (Marquette University, Dept. of Mechanical Engineering, Haggerty Engineering Building, 1515 W. Wisconsin, Milwaukee, WI 53233) Source: Proceedings of the ASME Power Conference, 2005, v PART A, p 95-100, 2005, Proceedings of the ASME Power Conference, 2005: Includes Papers from the 2005 International Conference on Power Engineering, ICOPE In this paper the numerically determined pressure increase (AP) versus volumetric flow rate (CFM) curve at a given fan speed for a plenum fan is compared to experimental data. The simulations were carried out using a rotating fan blade section and a fixed inlet and outlet plenum with a three-dimensional tetrahedral computational mesh. The objective of this work is to assess the feasibility of approximating a 36" plenum AP-CFM fan curve using a low order computational approach and thereby assessing the effectiveness of using such an approach as a real time design tool. The measures of success of this work include demonstrating the ability to capture pertinent characteristics of the fan curve such as slope and roll-off of the ΔP-CFM curve. It was found that a fairly high resolution was required near the fan blade section in order to better approximate the Δ-CFM curve. This higher resolution greatly increased the runtime. In addition, including a k-e turbulent model improved the pressure drop characteristics as compared having no turbulence model. It is hoped that an approach such as this will be adopted in the real time design and manufacture of plenum fans . Copyright 2005 by ASME
转动的无蜗壳离心风机压降的数值模拟
本文的数值确定了给定无蜗壳离心风机的转速时，压力增加（AP 大气压）与体积流量（立方英尺CFM ）的曲线，并与实验数据进行了对比。对旋转风机叶片部分和固定的进出口，采用三维四面体计算网格进行了数值模拟。本研究的目的是使用低阶的计算方法来评估36" 左右的无蜗壳风机AP-CFM 曲线的可行性，从而评估使用这种方法作为实时设计工具的有效性。本研究取得成功的措施包括展示了捕捉风机曲线的相关特性，如斜率和下降的 ΔP-CFM 曲线的能力。研究发现，风机叶片部分需要较高的分辨率以更好地近似Δ-CFM 曲线。这种高分辨率大大增加了运行时间。此外，与没有湍流模型相比，κ-ε湍流模型改善了压降的特性。希望这样的方法能用于无蜗壳离心风机的实时设计和制造中。
Maximum Achievable Efficiency of Centrifugal Fans Without Housing 1
XIA Yingan
The present paper is focused on centrifugal fan wheels with backward curved blades and a rotating diffuser in free-blowing operating (without housing). Moreover, the consideration is confined to the flow area within impeller.
Such centrifugal fans are very popular for the use in air handling units because of advantages such as compact design and direct drive etc.. The fan efficiency ηr is, however, a little lower than the fan with housing, which converts the dynamic flow energy of the air directly into usable static flow energy. There is no doubt a further potential to improve the efficiency through a further aerodynamic optimization of the wheel geometry. It is, however, exciting to know on which pa rameters the efficiency of these fans ηr primarily depends and what is the theoretic limit of the efficiency maximum achievable ηr,max.
The basis for the theoretic consideration is the Euler's main equation, which describes the energy conversion in the fan wheel. For an idealized flow within the fan wheel the relation between the fan efficiency ηr and the hydraulic efficiency of the blading (incl. inflow and outflow from the wheel) ηhydr is derived in function of the other technical operating and geometric parameters.
A theoretic estimation of the expected efficiency ηr of an aerodynamically "lossfree" fan can be carried out by ηhydr = 1. Inversely from the really measured/achieved efficiency ηr of a fan, the theoretic, hydraulic efficiency ηhydr can then be estimated as to the introduced formula aiming at evaluating the potential for a realistic improvement.
Three wheel examples with different blade geometries show how much the efficiency of a fan without housing depends on the working point (air volume and pressure) apart from the blade geometry. The limit of the maximum efficiency achievable of a centrifugal fan should in fact be higher than the real value of 73% presently achieved at the working point with a dimensionless volume number: 0.26 and a dimensionless pressure number: 0.57. The margin for a further improvement through an aerodynamic optimization of the flow in the wheel should, however, be highly limited for this wheel due to the high value already achieved.
In order to increase the total efficiency of the fan, the efficiency of other components like motor, control, etc. has to be improved as well
无蜗壳离心风机可实现的最大效率
本文的重点是离心风机轮向后弯曲的叶轮和自由进风的旋转扩散器（无蜗壳）。此外，考虑的仅限于叶轮内的流通区域。
这种离心风机在空气处理机组应用广泛，是因为具有设计紧凑和直接驱动等优点。但是，该风机效率ηr略低于有蜗壳离心风机，它将空气的动能直接转化为可用的静能。毫无疑问的是通过优化叶轮的几何来进一步提高潜在的效率。令人兴奋的是知道了这类风机的效率ηr主要依赖于哪些参数，及可实现的最大效率的理论极限。
理论考虑的基础是欧拉方程，它描述了风机叶轮中的能量转换。对风机叶轮内的理想化流动，风机效率ηr和叶片（包括叶轮的进出口）的水力效率ηhydr的关系由其它技术操作和几何参数推导出。
理论估计预期的“无损”风机的空气动力学效率ηhydr= 1。它与实测的风机效率ηr成反比，理论上，水力效率ηhydr可以被引入用于评估实际的改进可能性的公式。
不同叶片几何的三种叶轮实例表明无蜗壳离心风机的效率除取决于叶片的几何形状外，还取决于工作点（风量和压力）。离心风机可利用的最大效率实际上高于现在在工作点（无量纲的风量为0.26，无量纲的压力为0.57）能达到的73%的真实值。然而，通过叶轮的空气动力学优化得到的改善是很有限的，因为该叶轮目前达到的值已经很高。
为了增加风机的总效率，和其他部件，像电机、控制器等的效率，还需要做进一步的改善。
Lilly 等人对直径为36的无蜗壳离心风机的声功率级按照AMCA 300-67的标准进行了直接测量。结果表明，在同一工作点时，无蜗壳离心风机的声功率级远远低于传统的涡旋离心风机。较低的声功率水平和垂直配置，使无蜗壳离心风机非常适合于高层办公楼典型的一层层的空气处理机组。并举例说明这种类型的系统可以安装在一个开放的办公区附近，无需使用传统的隔音设备或砌体隔墙，仍使噪音达到可接受的水平。
1
Coward 等人认为无蜗壳离心风机的性能如蜗壳离心风机一样是能被预测的，但必须通过工程分析，并使用良好的可追踪的数据。无涡壳风机空气动力学性能的计算机建模将有助于减少未来的性能问题。并且可以使用计算流体动力学（CFD ）方法数值模拟排气室内的温度和速度等值线来优化通风设计。 1
Sadi 等人研究了空气处理机组对无蜗壳离心风机的性能和声音的影响。Ziehl-Abegg 风机的新高性能C 叶轮经过空气处理机组测试段进行测试，使用照片和图纸来描述原型和测试部分。此外使用线型探针使叶轮出口的流动可视化，并使用高速摄像机来拍摄照片，结合粒子图像测速方法，测量叶轮出口处的流速。实验研究结果将用于改善C 叶轮以及定义计算空气处理机组对风机性能影响的算法。 2
Borg 数值确定了给定无蜗壳离心风机的转速时，压力增加（AP 大气压）与体积流量（立方英尺CFM ）的曲线，并与实验数据进行了对比。其目的是使用低阶的计算方法来评估36" 左右的无蜗壳风机AP-CFM 曲线的可行性，从而评估使用这种方法作为实时设计工具的有效性。研究发现，风机叶片部分需要较高的分辨率以更好地近似Δ-CFM 曲线，但高分辨率大大增加了运行时间。此外，与没有湍流模型相比，κ-ε湍流模型改善了压降的特性。 2
XIA Yingan 等人研究了无蜗壳离心风机轮向后弯曲的叶轮和自由进风的旋转扩散器，仅限于叶轮内的流通区域。得出结论：无蜗壳离心风机的效率ηr略低于有蜗壳离心风机，它将空气的动能直接转化为可用的静能，可以通过优化叶轮的几何来进一步提高它的潜在的效率。不同叶片几何的三种叶轮实例表明无蜗壳离心风机的效率除取决于叶片的几何形状外，还取决于工作点（风量和压力）。离心风机可利用的最大效率实际上高于现在在工作点（无量纲的风量为0.26，无量纲的压力为0.57）能达到的73%的真实值。然而，通过叶轮的空气动力学优化得到的改善是很有限的，因为该叶轮目前达到的值已经很高。
2