{"id":21285,"date":"2025-03-25T11:50:47","date_gmt":"2025-03-25T10:50:47","guid":{"rendered":"https:\/\/mag.ebmpapst.com\/en\/?p=21285"},"modified":"2026-04-21T11:52:09","modified_gmt":"2026-04-21T09:52:09","slug":"aerodynamics-optimizing-installation-situation-building-air-conditioning-with-simulation-radical-2","status":"publish","type":"post","link":"https:\/\/mag.ebmpapst.com\/en\/industries\/refrigeration-ventilation\/aerodynamics-optimizing-installation-situation-building-air-conditioning-with-simulation-radical-2_21285\/","title":{"rendered":"Opti\u00admizing resi\u00adden\u00adtial air condi\u00adtioning with simu\u00adla\u00adtion"},"content":{"rendered":"\n

At motor and fan manu\u00adfac\u00adturer ebm-papst, advanced numer\u00adical simu\u00adla\u00adtion tools for calcu\u00adlating fluid mechanics are part of everyday devel\u00adop\u00adment. For many years, the company\u2019s engi\u00adneers have been working on devel\u00adoping their fans using powerful CFD tools, not only for opti\u00admizing complex impeller geome\u00adtries, but also for motor or elec\u00adtronics cooling concepts or in the context of acoustic testing for noise char\u00adac\u00adter\u00adis\u00adtics. Customers can also benefit from this exten\u00adsive know-how if they seek support in the aero\u00addy\u00adnamic devel\u00adop\u00adment of their own end devices in which ebm-papst fans are to be used.<\/p>\n\n\n\n

RadiCal 2: High air flow and quiet oper\u00ada\u00adtion<\/h2>\n\n\n\n

The RadiCal 2 series shows how aero\u00addy\u00adnamic opti\u00admiza\u00adtions of this kind have an impact in prac\u00adtice. The compact centrifugal fans have been designed to deliver high air flows at low back pres\u00adsure while oper\u00adating as effi\u00adciently and quietly as possible (Fig. 1). Several design details contribute to this, making it possible to achieve a \u2018wound\u2019 blade geom\u00adetry that helps signif\u00adi\u00adcantly increase effi\u00adciency and reduce noise. Not only the blade shape, but also the profile of the inlet and outlet edges has been revised. This improves the flow behavior while at the same time increasing the strength of the fan impeller, which is made of resis\u00adtant plastic. <\/p>\n\n\n

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The wavy cover plate also improves the aero\u00addy\u00adnamic char\u00adac\u00adter\u00adis\u00adtics and there\u00adfore air perfor\u00admance. With the centrifugal module, i.e. the housing box, the inclined struts further increase the air perfor\u00admance. The axial height of the struts is selected to fill the back\u00adflow areas in the best possible way. There is also an enlarged intake diam\u00adeter, which ensures a greater air flow rate through the impeller.<\/p>\n\n\n\n

The opti\u00admized Flow\u00adGrid air inlet grille also helps to prevent noise. Compared to the earlier series version, both the intake side distur\u00adbance and the fan itself is quieter, by at least between 1 and 3 dB(A). As the rotor area had a major impact on noise, the air inlet grille was also given a cap over the area of the motor. This enables the disrup\u00adtive blade passing noise in the lower frequency range in partic\u00adular to be signif\u00adi\u00adcantly reduced. With regard to the envi\u00adron\u00admental factor of \u201cnoise\u201d, the fans there\u00adfore meet the strictest require\u00adments.<\/p>\n\n\n\n

Air guide moduls for greater effi\u00adciency<\/h2>\n\n\n\n

The centrifugal fans in the RadiPac product range were designed and engi\u00adneered espe\u00adcially for use in air condi\u00adtioning and ambient air devices and have been constantly improved over the past few years. Higher speeds ensure greater air flow and higher pres\u00adsures, meaning that even appli\u00adca\u00adtions with more than 2000 Pa static pres\u00adsure increase can be covered. (Fig. 2) In addi\u00adtion, noise gener\u00ada\u00adtion has decreased further; depending on the oper\u00adating point, the noise level is reduced by between 3 and 7 dB(A) compared to the prede\u00adcessor series.<\/p>\n\n\n

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Fig 2: New RadiPac product range: Increase in power density compared to the prede\u00adcessor series (Graphic | ebm-papst)<\/figcaption><\/figure>\n<\/div>\n\n\n

Special air guide modules increase the effi\u00adciency again by up to five percent (Fig. 3). This is achieved by reducing the outlet losses. For this purpose, ebm-papst has devel\u00adoped a housing for the RadiPac, consisting of four segments. The module segments are made of galva\u00adnized sheet steel and have an aero\u00addy\u00adnamic shape. This special shape slows down the flow, which reduces the dynamic pres\u00adsure compo\u00adnent and increases the usable static pres\u00adsure compo\u00adnent (Fig. 4). At the same oper\u00adating point, the fans can run at a lower speed, which in turn has a lower energy consump\u00adtion and lower noise emis\u00adsions. The RadiPac C Perform has exactly the same mounting hole pattern as the industry stan\u00addard, making it easy to change over.<\/p>\n\n\n\n

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Fig 3: In the RadiPac C Perform centrifugal fan, the four-part air guide module reduces outlet losses, increasing the effi\u00adciency by up to 5 percentage points. This enabled the proven support bracket to be retained. (Image | ebm-papst)<\/figcaption><\/figure>\n<\/div>\n\n\n\n
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Fig 4: The design measures delay the flow, which reduces the dynamic pres\u00adsure compo\u00adnent and increases the usable static pres\u00adsure compo\u00adnent. (Graphic | ebm-papst)<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n

With CFD simu\u00adla\u00adtion for optimum fan use<\/h2>\n\n\n\n

To ensure that the fans really play out their strengths, unfa\u00advor\u00adable inter\u00adac\u00adtions cannot occur after instal\u00adla\u00adtion in venti\u00adlation and air condi\u00adtioning units. That is why it is advis\u00adable to simu\u00adlate the instal\u00adla\u00adtion situ\u00ada\u00adtion for aero\u00addy\u00adnamics in the early devel\u00adop\u00adment phases of a customer device. The fan\u2019s energy consump\u00adtion and sound depends on how the housing encour\u00adages air flow, whether it is drawn in axially from the front, centrifu\u00adgally from all sides or on one side. In poor cases, this can double the power consump\u00adtion or halve the effi\u00adciency, and can signif\u00adi\u00adcantly increase the noise level. CFD helps in under\u00adstanding the aero\u00addy\u00adnamic condi\u00adtions in the device (Fig. 5).<\/p>\n\n\n\n

Before the simu\u00adla\u00adtion begins, the objec\u00adtive should first be defined and a few ques\u00adtions answered. Does air have to flow through a heat exchanger as evenly as possible? Is the simu\u00adla\u00adtion supposed to detect pres\u00adsure losses? Does the customer want to perform a general check on the choice of fan? Is the device in which the fan oper\u00adates supposed to be as quiet as possible? Once the goal has been clar\u00adi\u00adfied, the 3D CAD data and the expected oper\u00adating point (pres\u00adsure, air flow, speed) of the fan provide the basis for simu\u00adla\u00adtion. <\/p>\n\n\n\n

Fig. 5: Visu\u00adal\u00adiza\u00adtion of air flow through a venti\u00adlation unit. (Graphic | ebm-papst)<\/figcaption><\/figure>\n\n\n\n

In addi\u00adtion, there are also char\u00adac\u00adter\u00adistic curves from the filters, heat exchangers or guard grills installed in the device, for example. The data are cleared up and unnec\u00ades\u00adsary details are removed (cleaning). Then the simu\u00adla\u00adtion is prepared in a prepro\u00adcessing phase, meaning that certain boundary condi\u00adtions are spec\u00adi\u00adfied and the geome\u00adtries are networked. The grid struc\u00adture divides the space that the air passes through into many indi\u00advidual cells, which form the basis of the math\u00ade\u00admat\u00adical calcu\u00adla\u00adtion. The simu\u00adla\u00adtions then run on high-perfor\u00admance computers.<\/p>\n\n\n\n

Prac\u00adtical exam\u00adples: Exploiting poten\u00adtial for opti\u00admiza\u00adtion<\/h2>\n\n\n\n

Using the simu\u00adla\u00adtion results, the engi\u00adneers then esti\u00admate the poten\u00adtial for opti\u00admiza\u00adtion and develop concrete sugges\u00adtions for improve\u00adment. For example, a customer devel\u00adoped an air purifi\u00adca\u00adtion device in which the fan was to be used for pushing air out. However, the simu\u00adla\u00adtion showed signif\u00adi\u00adcant turbu\u00adlence (Fig. 6), which increased the power consump\u00adtion at the oper\u00adating point. Using the fan to draw air in, i.e. changing its instal\u00adla\u00adtion posi\u00adtion, proved to be helpful here. The air flow is now very uniform, the power consump\u00adtion is decreased and there is also a posi\u00adtive effect on oper\u00adating noise. With an air condi\u00adtioner for ceiling mounting, the simu\u00adla\u00adtion proved that it is advan\u00adta\u00adgeous to use a centrifugal fan instead of the usual axial fan. <\/p>\n\n\n\n

This was initially coun\u00adter\u00adin\u00adtu\u00aditive, as the oper\u00adating point of the device indi\u00adcated that an axial panel fan would be the best choice. However, switching to a large centrifugal fan made an air duct design according to the centrifugal impeller design possible, which meant that no addi\u00adtional deflec\u00adtion was required. This was reflected in a power saving of over 70% with a reduc\u00adtion in sound power level by 20 dB(A). The extent of the pres\u00adsure losses caused by the deflec\u00adtion of the air towards the side outlet was previ\u00adously always severely under\u00ades\u00adti\u00admated. <\/p>\n\n\n\n

Find and utilise poten\u00adtial with CFD<\/h3>\n\n\n\n
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After<\/h3>\n<\/div>\n<\/div>\n\n\n\n
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Fig 6: In an air purifi\u00adca\u00adtion unit, the air flow could be signif\u00adi\u00adcantly improved by changing the fan instal\u00adla\u00adtion posi\u00adtion. The power consump\u00adtion dropped and the device oper\u00adates more quietly. (Graphic | ebm-papst)<\/p>\n\n\n\n

Another example: Using simu\u00adla\u00adtion result once again, the effi\u00adciency of a heat pump could be signif\u00adi\u00adcantly improved. Thanks to geometric changes, the pres\u00adsure losses in the device fell by a total of 17 percent. The indi\u00advidual sub-areas in the device were assessed sepa\u00adrately and the product design was adapted accord\u00adingly. The user has also bene\u00adfited from the options offered by CFD simu\u00adla\u00adtion.<\/p>\n\n\n\n

These exam\u00adples show that it is worth\u00adwhile for end device manu\u00adfac\u00adturers to rely on numer\u00adical flow simu\u00adla\u00adtion and to apply these at an early stage of devel\u00adop\u00adment to avoid subse\u00adquent revi\u00adsion costs. ebm-papst supports this with its long-standing CFD expe\u00adri\u00adence and offers such eval\u00adu\u00ada\u00adtions and calcu\u00adla\u00adtions to ensure that the fans operate as effi\u00adciently as possible in the appli\u00adca\u00adtion. Even small opti\u00admiza\u00adtions to the instal\u00adla\u00adtion situ\u00ada\u00adtion can reduce pres\u00adsure losses, increase effi\u00adciency, or mini\u00admize running noise.<\/p>\n\n\n\n

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Centrifugal fans with forward and back\u00adward-curved blades<\/h3>\n\n\n\n

Centrifugal fans from ebm-papst are avail\u00adable with forward and back\u00adward-curved blades. The quiet-running centrifugal fans with forward-curved blades are also supplied with a scroll housing. The centrifugal fans with back\u00adward-curved blades are designed as free\u00adwheel fans and do not require a scroll housing. In the case of centrifugal fans with external rotor motors, the motor is posi\u00adtioned in the impeller, ensuring not just optimum cooling of the motor, but also a partic\u00adu\u00adlarly compact design. The entire range is avail\u00adable with both AC and EC tech\u00adnology. In addi\u00adtion to being partic\u00adu\u00adlarly energy-saving, the inte\u00adgrated elec\u00adtronics also make it possible to imple\u00adment any control, moni\u00adtoring and main\u00adte\u00adnance func\u00adtions \u2013 for both the smart home and Industry 4.0.<\/p>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"

At motor and fan manu\u00adfac\u00adturer ebm-papst, advanced numer\u00adical simu\u00adla\u00adtion tools for calcu\u00adlating fluid mechanics are part of everyday devel\u00adop\u00adment. For many years, the company\u2019s engi\u00adneers have been working on devel\u00adoping their fans using powerful CFD tools, not only for opti\u00admizing complex impeller geome\u00adtries, but also for motor or elec\u00adtronics cooling concepts or in the context [\u2026]<\/p>\n","protected":false},"author":36,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"wp_typography_post_enhancements_disabled":false,"footnotes":""},"categories":[16,9],"tags":[],"class_list":["post-21285","post","type-post","status-publish","format-standard","hentry","category-fans","category-refrigeration-ventilation"],"acf":[],"_links":{"self":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts\/21285","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/users\/36"}],"replies":[{"embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/comments?post=21285"}],"version-history":[{"count":8,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts\/21285\/revisions"}],"predecessor-version":[{"id":22933,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts\/21285\/revisions\/22933"}],"wp:attachment":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/media?parent=21285"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/categories?post=21285"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/tags?post=21285"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}