The propeller efficiency curve shown in Figure 1 is a composite of both the typical Bonanza two and three blade propellers at two different conditions. Centrifugal fans are typically used for lower flows and higher pressures. Note that compliance with EU 327/2011 is based on calculation, as we manufacture bespoke one off units individual fan tests are not possible. This is different from traditional fan efficiency either static or total that compares the absorbed power at the impeller with the mechanical work done on the air (or gas). Another feature that has occurred in the last 5-10 years is efficiency of fan motors. The overall efficiency can be expressed as: η = ηh ηm ηv                               (4). Even if for example the motor is free issued we can use the correct motor efficiency supplied by the customer, or in the absence of this, then the minimum required motor efficiency eg IE2 or IE3. ERP is a European Union (EU) for Energy-Related Products. The first thing to note is that the “fan efficiency” is for the complete fan assembly, including impeller, drive motor and VSD (if fitted). Mechanical components - like transmission gear and bearings - creates mechanical losses that reduces the power transferred from the motor shaft to the pump or fan impeller. Commonly known as ATEX fans, Fans designed for operation with high temperature air above 100OC, Where ambient gas temperatures exceed 65OC or fall below -40OC, Where the supply voltage to the drive motor >1000 V AC or 1500 V DC, Fans for use with toxic, corrosive or flammable gasses or subject to abrasive substances. Another aspect of AMCA FEGs is that their value depends on the fan size. All fans are supplied as a complete assembly. Specifically regulation (EU) No 327/2011 sets minimum efficiency standards for Fans driven by electric motors with electrical input powers between 125Watts and 500 kWatts. In absence of specific information regarding variable speed drives, if fitted, an efficiency of 98% will be applied along with a “part load compensation factor” as defined in  clause 3.2 of Annex II of  EU327/2011. ?_t=transmission drive efficiency=0.96 (clause 3.2 annexII) Figure 1 shows a typical fan curve (green) with two numerated system lines (dashed), and the rated efficiency curve. As specified in EU 327/2011 efficiency calculations are based on “best efficiency point”. CalQlata has tried to keep the operation of this calculation option as simple as possible, given that it is recommended for general purpose calculations only and not for actual purchase specifications (see Fan Calculator – Technical Helpbelow). The fan efficiency is the ratio between power transferred to airflow and the power used by the fan. ?_vsd=variable speed drive efficicney if fitted=0.98 (estimate) Fans fall … If the specific motor efficiency is not available motor efficiency can be estimated using clause 3.2 of Annex II of  EU327/2011. They represent the year’s very best for energy savings and environmental protection. When evaluating your fan, the fan curve can be a useful tool to understand why the efficiency may be low at the given operating point. This should also include the velocity pressure on the inlet side (if known) that is constant and in-line with the fan. In case of direct driven fan, it indicates fan’s aerodynamic ability to convert impeller power to air power. Fan and blower selection depends on the volume flow rate, pressure, type of material handled, space limita- tions, and efficiency. We do this regardless of actual installation of the fan which could be B,C or D because the vast majority of fans we supplied with a contractual static pressure requirement. The “S” denotes the selection point for the desired performance. The volumetric efficiency can be expressed as: ηv = q / (q + ql)                               (3), q = volume flow out of the pump or fan (m3/s). The operating environment of a typical engine-cooling fan has favored axial-flow fans, and, at the same time, posed obstacles to successful adoption of alternative fan types. Why are ceiling fans becoming more efficient by each passing day? This is then corrected using the fan laws to derive performance for different sized fans running at different speeds and operating at different densities. The use of a “systems approach” in the fan selection process will typically yield a quieter, more efficient, and more reliable system. Fans where the work per unit mass exceeds 25 kJ/kg. In absence of specific information regarding vee belt drives, if fitted, these will be calculated using clause 3.2 of Annex II of  EU327/2011 “low efficiency drive”. P = electrical power input (note at this stage before the calculation is done this can only be estimated whereas for a verification test it would have to be measured) In this case assume 11 kW the motor rating this gives a slightly higher value for the target efficiency. Note items 9 & 10 of the above clause are not relevant to bespoke fans where the performance is derived from fan tests and scaled using dimensionally similarity fan laws. Fan noise 7/12/2000 11.2 Fan Application The choice of a fan depends on the desired ventilation requirements (volume, … Fig 2shows the pressures through a fan, each of which is described below: Inlet Pressure; is the static pressure on the inlet side of the fan. If you want to promote your products or services in the Engineering ToolBox - please use Google Adwords. Centrifugal fans are calculated using measurement category A,C with efficiency based on “static”. Static Fan Efficiency (%): Brake Horsepower (HP): Air Density: Barometric Pressure (in Hg): Temperature (F) Density (lb/Cu.ft. Only emails and answers are saved in our archive. Given their size, it’s not surprising house fans consume more power than ceiling fans. The losses in a pump or fan converts to heat that is transferred to the fluid and the surroundings. The performance curve for the axial fan is shown in the figure. As the overall efficiency is > than target efficiency fan is compliant. AddThis use cookies for handling links to social media. The overall efficiency can be expressed as: η = η h η m η v (4) where. 6.5.3.1.3 Fan Efficiency. Woodcock & Wilson 600mm dia BFN Single Inlet Single Width (SISW) fan running at 2000 rpm. Fan Efficiency for Dust Collectors. For this Absorbed power (of the impeller) is 7.71 kW. The Fan Total Efficiency field (simply 'Fan Efficiency' in OpenStudio) will need to be adjusted to represent the change in motor efficiency and fan power consumed. By replacing a less efficient model with a highly efficient one, it is possible to save on average around 20% of its running costs during its lifetime (15 years). Kps compressibility coefficient of fan static gas power taken as 1 as this is already calculated in the fan testing carried out to BS EN 5801. New fan-efficiency metrics developed by AMCA International—fan energy index (FEI) and fan electrical power (FEP)—can be used to right-size fans and reduce power consumption in commercial and industrial air systems. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected. At half its rated operating speed, the fan delivers 50% of its rated airflow but requires only 1/8 full-load power. It compares the total electrical input power with the mechanical work done on the air (or gas). Reference to the fan curve figure 1 shows the best efficiency point to be 2.81 m3/sec at 2.08 kPa static pressure. The air enters the fan wheel through the housing inlet, turns 90 degrees and is accelerated radially and exits the fan housing. Static Fan Efficiency = Volume (m3/s) * Pressure gain (Pa) / Power input (W) * 100 But, if the pressure is measured in mmWC instead of Pascals and Power is expressed in kW, the formula can be derived as follows;- 1 mmWC = 9.81Pa Therefore 1Pa = 1/9.81 = 0.102 mmWC (or, divide mmWC by 0.102 to get Pa) The overall efficiency is the ratio of power actually gained by the fluid to power supplied to the shaft. For a fluid flow process involving a pump or fan the overall efficiency is related to the. P_e=7.71×1000×1/0.914×1/0.96×1/0.98×1/1.04, Step 3 compare calculated efficiency with target efficiency. Centrifugal fans often contain a ducted housing to direct outgoing air in a specific direction or across a heat sink; such a fan is also called a blower, blower fan, biscuit blower [citation needed], or squirrel-cage fan (because it looks like a hamster wheel). Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications! CN = 10 + 10 log10 (1-η)/η typical values: η Cn 90% 0 75% 5.2 40% 12.2 η= Hydraulic efficiency of the fan = Q×P/(6350×HP) HP = nominal horsepower of the fan drive motor . They need to get the dust-laden air past the filters in the dust collector baghouse. No high performance alternatives. Typical impeller diameters range from 4 to 80 cm. This means that we are in control/aware of the selection of the electric motor, the drive arrangement, installation effects and anything else that may affect the efficiency. The pump must be constructed for the specific work: Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro .Add the Engineering ToolBox extension to your SketchUp from the SketchUp Pro Sketchup Extension Warehouse! Target total efficiency of fans according to requirements of EU fan regulation. Typical Pump Efficiencies Pump only (brake, no motor) Non-clog centrifugal, 25 hp: 65% Submersible wastewater, 34 hp: 75% Vertical turbine, water, 30 hp: 81% End Suction, water, 30 hp: 75% Bigger is better: add about 5 points at 200 hp Slower is better: add a couple points below 1200 rpm Energy-efficient whole-house fans. Due to leakage of fluid between the back surface of the impeller hub plate and the casing, or through other pump components - there is a volumetric loss reducing the pump efficiency. Smaller fans are inherently less efficient than larger fans. Stay tuned to be able to search FEI rated fans … The actual water head (water column) can be calculated as: = ((10 105 N/m2) - (1 105 N/m2)) / (1,000 kg/m3) (9.81 m/s2). The regulation sets out the information to be supplied in clause 3 annex I of EU327/2011, however as set out above as we manufacture bespoke units it is not practical to publish, even on our website, efficiency data for all the possible fan units we may supply. As a rule of thumb - the temperature increase in a fan transporting air is approximately 1 o C. Example - … Consequently, oversized fans not only cost more to purchase and to operate, they create avoidable system performance problems. Most industrial fans that fall between the above input power limits are covered by EU 327/2011. H2O) Round Duct Equivelent of Rectangular Duct: η = overall efficiency. ENERGY STAR Certified Most Efficient 2020 Ceiling Fans. Currently we use the requirements set out for 1st  January 2015 onwards. Please read AddThis Privacy for more information. (The vertical line joining the maximum efficiency point is drawn which meets the Pressure curve at point "S") [1] The following can be inferred from the curve - Type of fan Peak Efficiency Range Centrifugal Fan Airfoil, backward curved/inclined 79-83 Modified radial 72-79 Radial 69-75 Pressure blower 58-68 Forward curved 60-65 Axial fan Vanaxial 78-85 Tubeaxial 67-72 Propeller 45-50 Syllabus Fans and blowers: Types, Performance … According to the regulation on fans, the efficiency of fans must be always given as a total efficiency of the fan assembly, i.e. en: pump fan efficiency power shaft fluid. You can target the Engineering ToolBox by using AdWords Managed Placements. We don't save this data. Drive loss is based on full load motor power (11 kW) ie Pa = 11 kW, VSD power Taken as motor full load power ie Ped = 11 Kw, Registered in England No. Products that make the ENERGY STAR Most Efficient list for 2020 deliver cutting edge energy efficiency along with the latest in technological innovation. Note this is not an exhaustive list. This paper provides an analysis of costs and benefits of several options to improve the efficiency of ceiling fans to assess the global potential for electricity savings and green house gas (GHG) emission reductions. typical ventilation rate of 10 m³/h per m² floor, and a typical SFP of 3.kW/(m³/s), operating 4 3000 hrs/yr, the fan energy accounts for: m²yr kWh 28 yr h 3000 m³/s kW 3.4 3600s 1h m² m³/h 10 × × × = which is 17% of the total energy use of an efficient (lower quartile) existing office building . As a rule of thumb - the temperature increase in a fan transporting air is approximately 1oC. The typical characteristics of axial fans can be studied from the performance curves. The impellers have 30–40 short-chord blades that are manufactured from thin sheet plates. Also, actual installed efficiency is typically worse than the manufacturer's rating data indicates, dropping the fan's efficiency by 10 to 30 percent in some cases. Ceiling fans contribute significantly to residential electricity consumption, especially in developing countries with warm climates. An inline water pump works between pressure 1 bar (1 105 N/m2) and 10 bar (10 105 N/m2). For example a given fan could be supplied with a dozen different motors, be direct or belt driven. Typical ranges of fan efficiencies are given in Table 5.2. The system pressure varies based on how “dirty” the filters are, and you can adjust the fan speed accordingly. Fans shall have a Fan Efficiency Grade (FEG) of 67 or higher based on manufacturers’ certified data, as defined by AMCA 205. Step 1 Work out “target efficiency” using table 2, “Centrifugal backward curved fan with housing” measurement category A,C Efficiency category “static”, Electrical input power will be less than 10 kW (note this is not the motor power it is the actual power drawn by the fan despite motor rating), N = Efficiency grade from table 2 (right hand column) 61. Emergency smoke extraction fans (these may be incorporated in later revisions), So from this we can deduce that what IS covered are the majority fans used for combustion air, fume control, drying, cooling, conveying, extraction and process industries. Understanding Different Types of Fan Motors I last talked about high efficiency furnaces that are 95-98% efficient. C_c=Part load compensation factor= 1.04 Basically anything not covered by the specific exception IS covered by EU 327/2011. Because airpower is the product of flow and pressure, a fan working in the free air condition (no backflow pressure) has … Most of the fans were in the 60 to 75 cfm/watt range. Step 2 work out the fans actual efficiency using clause 3.1 Annex II, P_us=q × p_sf×k_sp P_us=2.81 × 2080×1.0=5844.8, Pe cannot be measured therefore is calculated as follows, P_e=impeller power×1/?_m ×1/?_t ×1/?_vsd ×?1/C?_c, ?_m=motor efficiency=0.914 IE3 11 kW 4 pole The actual efficiency of a fan depends on its power requirement (high power fans are on average more efficient than low power fans) and type. Fans There are two primary types of fans: centrifugal and axial. © Woodcock & Wilson Limited 2020 | Website Terms & Conditions | Privacy Policy | Site Map, Energy Efficiency & ERP for Woodcock & Wilson bespoke Industrial Fans, Fans for use in potentially explosive atmospheres. hp to an exhaust fan when operated at its full rated speed. 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