Square Cased Mixed Flow Fans

MFB series Mixed Flow ‘Square’ Ducted Fans Advanced, flexible performance fan technology Contents Multiflow Technology Performance Data Electrical Data Dimensional Data • Less space • In-line or end of duct fitting Other Elta Products Multiflow MFB benefits • More performance Multiflow is a trade name of Elta Fans

Multiflow Technology Benefits Advanced fan engineering Elta Multiflow technology provides for the first time, the ability to select a single direct driven mixed flow fan that can meet a wide selection of alternative performance contours and duty The secret of Elta Multiflow requirements. With fixed blade designs, the choice is either to make a technology lies in its extensively selection from a limited number of fixed performance contours or, researched and patented mixed consider the more costly and less space efficient flow impeller, which incorporates belt driven varients. adjustable blade...

Mixed Flow Air Performance Benefits • Non-stall characteristic The inherent aerodynamic benefits of good mixed flow • Non-overloading power curve impeller design provide marked advantages over conventional axial and centrifugal air performance • Wide operating range characteristics. Mixed flow ‘non stall’ airflow properties and a non overloading absorbed power curve allow a • Greater pressure capability than axial fans wide range of operating performance to be acheived. • Greater airflow capability than centrifugal fans Comparative curves MULTIFLOW ‘MIXED FLOW’ Multiflow, mixed flow performance...

Standard Multiflow MFB Range The Multiflow MFB fan range has been designed to provide customers with all the inherent benefits of Elta mixed flow technology by optimising design and performance choice. 9 fan sizes each with 2 alternative speeds and a selection of 5 alternative, factory set impeller blade angles for each model, provide an impressive choice of 90 standard model/performance options. MFB Standard supply comprises Square cased model with industry standard flanges at both ends. Wired terminal box, ready for customer installation. Motor and stator Guide Vanes

Basic Fan Model Reference Improved Performance The unique design of Multiflow MFB fans enables the required performance to be attained from a smaller fan size than is normally achievable with typical conical style, fixed blade mixed flow fans. As the airstream leaving a Multiflow MFB impeller is more axially orientated, it permits the casing to be closer to the impeller periphery, without incurring losses; so retaining excellent air performance, power and sound levels. Also, as Multiflow MFB incorporates an impeller of relatively wide air passage design, the resultant air throughput is greater...

Airflow Performance Data Elta fan performance data is achieved through exhaustive testing in the Company’s laboratory and provides an accurate and reliable record of the MFB series performance. Testing has been performed for Type D installation category (fully ducted) to the following current standards. Aerodynamic Performance To ISO 5801 : 1997 (incorporating BS 848 Part 1:1997) Sound Performance To BS 848 Part 2 : 1985 on both Inlet and Outlet sides Pressure Values The ISO 5801 standard suggests that fan pressure should be shown as total or stagnation values, with static pressure illustrated...

How to read Air Performance Data – typical example Model Reference Impeller Speed Sound Level overall In-duct Sound Density 1.2kg/m Overall inlet side 120 For sound level spectra or below this contour refer to Sound Level notes and table below Volume/Pressure Characteristic when operating above sound level data below Pd, Fan Dynamic Pressure Curve opposite page Impeller Blade Setting selected blade angle Factory pre-set blade For the MFB 350 at 1440 rpm as shown, a fan selection using blade setting 5 is appropriate with an absorbed power at duty condition of 0.058 kW (peak power 0.060kW). Refer...

0.06 Fan impeller power - KWatts Fan impeller power - KWatts 0.02 Sound Level The values shown on the performance curve above are the overall Sound Level The values shown on the performance curve above are the overall In-duct Sound Power levels on the outlet side of the fan unit. (rel. to 1pW). In-duct Sound Power levels on the outlet side of the fan unit. (rel. to 1pW). Inlet side values vary by 0dB. Inlet side values vary by -1.0dB. The overall dBW values may be adjusted by the ‘A’ reductions in the table below, so The overall dBW values may be adjusted by the ‘A’ reductions in the table below,...

Fan impeller power - KWatts 0.25 Fan impeller power - KWatts Sound Level The values shown on the performance curve above are the overall Sound Level The values shown on the performance curve above are the overall In-duct Sound Power levels on the outlet side of the fan unit. (rel. to 1pW). In-duct Sound Power levels on the outlet side of the fan unit. (rel. to 1pW). Inlet side values vary by 0dB. Inlet side values vary by -2dB. The overall dBW values may be adjusted by the ‘A’ reductions in the table below, so The overall dBW values may be adjusted by the ‘A’ reductions in the table below, so...

Fan impeller power - KWatts 0.12 Fan impeller power - KWatts 0.05 Sound Level The values shown on the performance curve above are the overall Sound Level The values shown on the performance curve above are the overall In-duct Sound Power levels on the outlet side of the fan unit. (rel. to 1pW). In-duct Sound Power levels on the outlet side of the fan unit. (rel. to 1pW). Inlet side values vary by -1dB. Inlet side values vary by +1dB. The overall dBW values may be adjusted by the ‘A’ reductions in the table below, so The overall dBW values may be adjusted by the ‘A’ reductions in the table below,...

Fan impeller power - KWatts Fan impeller power - KWatts Sound Level The values shown on the performance curve above are the overall Sound Level The values shown on the performance curve above are the overall In-duct Sound Power levels on the outlet side of the fan unit. (rel. to 1pW). In-duct Sound Power levels on the outlet side of the fan unit. (rel. to 1pW). Inlet side values vary by -1dB. Inlet side values vary by -1dB. The overall dBW values may be adjusted by the ‘A’ reductions in the table below, so The overall dBW values may be adjusted by the ‘A’ reductions in the table below, so as...