{"id":14005,"date":"2024-08-09T11:39:49","date_gmt":"2024-08-09T09:39:49","guid":{"rendered":"https:\/\/mag.ebmpapst.com\/en\/?p=14005"},"modified":"2024-09-13T12:25:35","modified_gmt":"2024-09-13T10:25:35","slug":"fans-for-air-water-heat-pumps","status":"publish","type":"post","link":"https:\/\/mag.ebmpapst.com\/en\/industries\/heating\/fans-for-air-water-heat-pumps_14005\/","title":{"rendered":"Fans for air\/water heat pumps"},"content":{"rendered":"\n

In prin\u00adciple, a heat pump works like a refrig\u00ader\u00adator, which with\u00addraws heat from the food stored in it and trans\u00adfers it outside. Air\/water heat pumps extract heat from the surrounding air and transfer the heat to the heating system, which warms the living areas or is used to heat water. Fans provide the needed air flow through the unit\u2019s evap\u00ado\u00adrator, with the best results always being achieved when the fans are driven by modern EC motors. They are energy-effi\u00adcient and very quiet, their speed is smoothly adjustable, and they have long service lives.<\/p>\n\n\n\n

Axial or centrifugal fan?<\/h2>\n\n\n\n
\n
<\/figure>\n\n\n\n

The RadiCal series<\/h3>\n\n\n\n

Learn more about the new gener\u00ada\u00adtion of the RadiCal series.<\/p>\n\n\n\n

\n
The best in its class  <\/i><\/a><\/div>\n<\/div>\n<\/div><\/div>\n\n\n\n

There are two types of air\/water heat pump; they are designed for indoor or outdoor instal\u00adla\u00adtion (Fig. 1a, 1b). The two types place different demands on the fans that are used (Fig. 2). In indoor instal\u00adla\u00adtions, outdoor air is drawn in through one duct and expelled later through another. Centrifugal fans are effec\u00adtive for this appli\u00adca\u00adtion as their design is suited to higher pres\u00adsure require\u00adments.<\/p>\n\n\n\n

Figure 1: Air\/water heat pumps for instal\u00adla\u00adtion indoors (left) and outdoors (right). (Image | BDH\/Solarpraxis AG)<\/figcaption><\/figure>\n\n\n\n

They are very compact, bene\u00adfiting the air\/water heat pumps that are also installed indoors where space is usually limited. This also applies for systems that combine the heat pump and the resi\u00adden\u00adtial venti\u00adlation unit (Fig. 3).<\/p>\n\n\n

\n
Figure 2: Char\u00adac\u00adter\u00adistic pres\u00adsure increase for axial and centrifugal fans. (Graphic | ebm-papst)<\/figcaption><\/figure>\n<\/div>\n\n\n

In contrast, space is usually not a problem for outdoor instal\u00adla\u00adtions, where the evap\u00ado\u00adrator is a sepa\u00adrate unit and a refrig\u00aderant line leads indoors. These config\u00adu\u00adra\u00adtions mainly use quiet-running axial fans.<\/p>\n\n\n\n

With both axial and centrifugal fans in various sizes, motor and fan specialist ebm-papst offers the right fan solu\u00adtion for every air\/water heat pump.<\/p>\n\n\n\n

Motor and fan specialist ebm-papst has now devel\u00adoped two new fan series for partic\u00adu\u00adlarly noise-sensi\u00adtive outdoor areas: Both are suit\u00adable for use with natural and flam\u00admable refrig\u00ader\u00adants and are partic\u00adu\u00adlarly quiet thanks to their special design, which helps prevent the heat pumps from becoming a disrup\u00adtive factor and allows them to blend in well with their surround\u00adings. While the AxiEco plug-in is suit\u00adable for heat pumps requiring a large pres\u00adsure reserve for the evap\u00ado\u00adrator, the AxiTone is geared more towards deliv\u00adering higher air flow at low back pres\u00adsure when the heat pump design requires this<\/p>\n\n\n\n

Figure 3: Air\/water heat pumps combined with resi\u00adden\u00adtial venti\u00adlation system. (Graphic | ebm-papst)<\/figcaption><\/figure>\n\n\n\n

Axial fan with high pres\u00adsure reserve<\/h2>\n\n\n\n

Ice forma\u00adtion partic\u00adu\u00adlarly affects evap\u00ado\u00adra\u00adtors when humidity precip\u00adi\u00adtates as ice on the heat exchanger at cold ambient temper\u00ada\u00adtures. This reduces the air routes and the drag, and so too the back pres\u00adsure. The fans then have to offer signif\u00adi\u00adcantly greater pres\u00adsure reserves. This is where the new AxiEco Plug-in comes in (Fig. 4). Studies have shown that its flow tech\u00adnology reduces ice forma\u00adtion and its air flow only reduces very slightly as the pres\u00adsure increases. This is also an advan\u00adtage for heat pumps, which heat in winter and cool in summer, as the oper\u00adating points then vary depending on oper\u00ada\u00adtion.<\/p>\n\n\n

\n
Figure 4: AxiEco plug-in (Image | ebm-papst)<\/figcaption><\/figure>\n<\/div>\n\n\n

The fan, which will be avail\u00adable in the 450 and 500 sizes typical for heat pumps in single- or two-family homes, has also been fitted with an air inlet grille. This Flow\u00adGrid, which acts as a recti\u00adfier for air flow, dras\u00adti\u00adcally reduces noise-gener\u00adating distur\u00adbances in the air flow. This reduces the sound pres\u00adsure over the entire frequency range, in partic\u00adular the disrup\u00adtive blade passing noise, i.e. unpleasant \u201chumming\u201d in the low frequency range.<\/p>\n\n\n\n

At the same time, the air inlet grille serves as a motor suspen\u00adsion and, if neces\u00adsary, the equip\u00adment manu\u00adfac\u00adturer can insert heating tape. The new axial fan weighs 30% less than the compa\u00adrable HyBlade version with steel wall ring. This means that less weight has to be handled during the instal\u00adla\u00adtion and the compact dimen\u00adsions often make it possible to opti\u00admize the design of the end device. The AxiEco Plug-in fans are supplied as a ready-to-install plug & play solu\u00adtion, including nozzle plate and Flow\u00adGrid.<\/p>\n\n\n\n

Quiet fan with three blades<\/h2>\n\n\n
\n
Figure 5: AxiTone (Image | ebm-papst)<\/figcaption><\/figure>\n<\/div>\n\n\n

For air\/water heat pumps, where high back pres\u00adsure tends to be the excep\u00adtion due to their design, the three-blade AxiTone \u2013 initially avail\u00adable in size 450 mm and later in sizes 500 and 630 mm (Fig. 5) \u2013 is the obvious choice. Its char\u00adac\u00adter\u00adistic curve is flatter, it supplies large volumes of air, and, as the name suggests, it makes very little noise during oper\u00ada\u00adtion.<\/p>\n\n\n\n

The blade geom\u00adetry plays a key role in both respects, as it has been opti\u00admized to aero\u00addy\u00adnamic criteria. The large area and steep incli\u00adna\u00adtion ensure high air flow, and the sickle-like shape reduces turbu\u00adlence and hence noise gener\u00ada\u00adtion.<\/p>\n\n\n\n

Other new features include the serra\u00adtions at the front edge of the blade. They also have a posi\u00adtive effect on the noise char\u00adac\u00adter\u00adis\u00adtics, as they mini\u00admize the tonal compo\u00adnents of noise. Condensers in resi\u00adden\u00adtial areas, where partic\u00adular atten\u00adtion must be paid to minimum noise emis\u00adsions, there\u00adfore also benefit from this quiet axial fan. The AxiTone is avail\u00adable as a ready-to-install motor-impeller combi\u00adna\u00adtion in both airflow direc\u00adtions, i.e., intake or blowing, and option\u00adally with a guard grill and support ring. It is also suit\u00adable for appli\u00adca\u00adtions with flam\u00admable refrig\u00ader\u00adants.<\/p>\n\n\n\n

\n
\n

Psychoa\u00adcoustics \u2013 how is a fan supposed to sound?<\/h3>\n\n\n\n
\n

Psychoa\u00adcoustics is concerned with describing personal sound percep\u00adtion in rela\u00adtion to measur\u00adable noise levels, i.e. it aims to explain why we perceive noises as pleasant or unpleasant. This is some\u00adthing that phys\u00adical measure\u00adments of sound levels in test rigs are unable to address. For example, trumpet music and a construc\u00adtion-site exca\u00advator have approx\u00adi\u00admately the same sound power but are perceived psychoa\u00adcousti\u00adcally in completely different ways. ebm-papst addressed this matter by setting up a special psychoa\u00adcoustic labo\u00adra\u00adtory<\/a> in which noise from fans in various config\u00adu\u00adra\u00adtions is played back for eight test subjects. Employees ques\u00adtion the subjects after\u00adwards to build up a scien\u00adtif\u00adi\u00adcally founded data\u00adbase based on the following psychoa\u00adcoustic para\u00adme\u00adters: loud\u00adness (unit: sone), sharp\u00adness (unit: acum), pitch (unit: mel), rough\u00adness (unit: asper) and fluc\u00adtu\u00ada\u00adtion strength (unit: vacil). Other impor\u00adtant quan\u00adti\u00adties are tonality and impul\u00adsive\u00adness. They can be measured with micro\u00adphones and compared with comments made by the test subjects. Assess\u00adments by the test subjects are analyzed with statis\u00adtical and psycho\u00adlog\u00adical methods. The results are used for product devel\u00adop\u00adment. The ulti\u00admate aim is to develop a fan whose oper\u00adating noise is perceived as pleasant by as many test subjects as possible.<\/p>\n<\/div><\/div>\n<\/div><\/div>\n\n\n\n

\n

CFD-simu\u00adla\u00adtion as a service<\/h3>\n\n\n\n
\n

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? CFD<\/a> can be used to calcu\u00adlate, visu\u00adalize and improve the flow condi\u00adtions in the customer device, or to compare different concepts with one another. 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. 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<\/div><\/div>\n<\/div><\/div>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"

In prin\u00adciple, a heat pump works like a refrig\u00ader\u00adator, which with\u00addraws heat from the food stored in it and trans\u00adfers it outside. Air\/water heat pumps extract heat from the surrounding air and transfer the heat to the heating system, which warms the living areas or is used to heat water. Fans provide the needed air [\u2026]<\/p>\n","protected":false},"author":12,"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":[16,8],"tags":[],"class_list":["post-14005","post","type-post","status-publish","format-standard","hentry","category-fans","category-heating"],"acf":[],"_links":{"self":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts\/14005","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\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/comments?post=14005"}],"version-history":[{"count":34,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts\/14005\/revisions"}],"predecessor-version":[{"id":21000,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/posts\/14005\/revisions\/21000"}],"wp:attachment":[{"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/media?parent=14005"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/categories?post=14005"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mag.ebmpapst.com\/en\/wp-json\/wp\/v2\/tags?post=14005"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}