Acoustic Laboratory TROX HESCO Schweiz AG
Contents Possible applications Reverberation chamber 4 5 Basic scheme of air handling unit and measuring equimpent 6 7 We are happy to advice you. If you have any questions concerning your acoustical problems our staff will be pleased to provide you with detailed answers. Contact labor@troxhesco.ch
Possible applications The Trox Hesco laboratory is mainly used for instrumentation testing and evaluation of complete air handling systems. The main focus of the laboratory is to measure and provide technical data within the product development process and for the product documentation. Totally 1700 m³ of laboratory premises are at the disposal for aero dynamical and acoustical measurements. On customer request it is also possible to provide acoustical test for any other product type. The acoustical laboratory is designed for general purposes but is primarily intended to be used for determination of sound power levels. Standard measurements easuring one test configuration takes about 0 s. To get all relevant acoustical data of a test object it is often necessary to make dozens of measurements. Following objects are particularly suitable for sound power level measurements: Grilles and diffusers Volume flow control devices Fire and smoke protection devices Fan coil units and air terminal units Ventilators Pumps Washing machines White goods In connection with air handling pressure drops and air temperatures are recorded additionally. Other measurements The acoustic measurement infrastructure allows us to analyze other poblems like: easurement of sound power levels of diffusers according to SN EN ISO 515 easurement of sabine absorbtion coefficients s according to SN EN ISO 54 easurement of insertion loss De of attenuators on the basis of SN EN ISO 75 Quality management acc. to ISO 9001 Since 199 TROX HESCO Schweiz AG has been certified according to ISO 9001. All measurements are performed with periodically calibrated equipment. The calibration and verification is carried out either internally or at a certified calibration authority. Definitions and symbols f L wr L pr Lr = frequency = sound power level of reference sound source = sound pressure level of reference sound source = L wr -L pr Note All details like e.g. device types, device manufacturers and references to standards are informative only. Trox Hesco AG reserves the right to change or modify the equipment if necessary or if it is requested due to new standards.
Acoustic Laboratory Possible test setup Reverberation chamber The reverberation chamber is used for the determination of the radiated acoustic power of any noise source. The room is designed to be very reverberant, so the walls are made of painted concrete. Besides the sloping ceiling and the tiled floor, the walls are non-parallel to make the room more diffuse. Additional diffusers randomly distributed in the room ensure the equal distribution of the sound energy. The whole chamber with its weight of 140 t is built on linear support elements to provide vibration isolation. Thus it is possible to reach very low background noise levels. The air handling unit is designed for flow rates up to 6000 m³/h (1670 l/s) at a total pressure drop of 000 Pa. To prevent acoustic measurements from being distorted by the noise of the supply and exhaust air handling units, the ducts are acoustically separated and fitted with highly effective attenuators. Reverberation chamber specifications Volume: 00 m³ Surface: 09 m² Weight: 140 tons, mounted on G+H linear support elements Compressed air supply up to 8 bar Water supply ND 5 Electric power supply 0 VAC / 10 A and 400 V / 15 A easuring air flow rate 4
Reverberation chamber according to SN EN ISO 741 Ground plan 500 100 500 600 1100 650 650 5460 7180 7400 60 1 400 850 60 1550 000 600 1100 1580 1170 1500 1 Supply air Exhaust air Entrance Developed view Room volume V = 00 m³ Surface A = 09 m² 5475 4490 5460 4900 5475 651 600 1100 650 1100 1650 650 7400 1870 1100 190 1 100 1100 651 180 950 670 460 7180 4900 00 1580 700 700 5
Basic scheme of air handling unit and measuring equipment 1 1a 5 T 1b T 5 4 A Pressure -, temperature- and speed transmitters B Sending unit (noise) C icrophone positions D Regulation of air handling unit A B C D 1 Supply air 1a Recirculation air 1b Outdoor air Exhaust air Reverberation chamber 4 ACA-nozzels 5 Attenuators Supply air unit onoblc S-Type K6 with 4 multileaf dampers, filtration unit, heating unit (4 different levels, 40 kw) and continuously adjustable ventilator (type SD-9-071/D 5-4 Fischbach). The supply air duct is fitted with splitter attenuators to ensure that the ventilator noise is lower than 0 db(a). Furthermore the duct close to the reverberation chamber is encased with steel plates to avoid sound irradiation into the duct. The supply air inlet into the chamber is 1.1 m high by 1.1 m width, which allows special measurement like e.g. attenuator measurements. For acoustic tests without air, the duct is air-tight sealed by steel plates. Exhaust air unit The unit is subdivided into two identical parts with continuously adjustable ventilators (type SD 8-980 / D 5-4 Fischbach) and automatic multileaf dampers. The exhaust air ducts are fitted with splitter attenuators to avoid perturbation of environmental noise. Other measurement equipment All measuring lines are routed through special connecting passages to the measuring unit: Air flow rate is measured with nozzles according to ACA-standard 10-67 (range 5 000 m³/h). Pressure differences are captured with Setra pressure transmitters and a Delphin data logger. Temperatures are measured with PT 100 sensors. 6
Acoustical measurement instrumentation Beside the real time analyzing system which simultaneously records the sound pressure levels of the three microphones, a reference sound source B&K type 404, an omni directional speaker system B&K type 441 and a microphone calibrator are at disposal. For measurements with air handling parts volume flow rates and pressure drops are recorded as well. On special request, an evaluation of the results in order to obtain NR or NC curves is possible. easuring the sound power level in accordance with SN EN ISO 741 is fully automated. The result sheets are available in different languages and contain following data: Sound power level in octave band and 1/ octave band both linear and a-weighted, Lr values, background noise corrections and integration time of the measurement. easurement equipment 4 1 Reverberation chamber acc. to SN EN ISO 741 6 5 1 Reference sound source B&K type 404 Omnidirectional speaker system B&K type 441 Condensator microphones B&K type 4179 4 icrophone preamplifiers B&K type 660 5 Puls Frontend B&K type 560C - LAN odul B&K type 75 - In-/Output odul B&K type 109 6 Software B&K Puls BZ 517 / CPB Analysis 7771 7
Headquarters TROX HESCO Schweiz AG Walderstrasse 15 Postfach 455 CH - 860 Rüti ZH Telefon +41 (0)55 50 71 11 Telefax +41 (0)55 50 7 10 www.troxhesco.ch info@troxhesco.ch Branch office / Romandy TROX HESCO Schweiz AG Route des Arsenaux 7 Case postale 57 CH - 1705 Fribourg Telefon +41 (0)6 45 59 00 Telefax +41 (0)6 45 59 01 www.troxhesco.ch info@troxhesco.ch Representation / Italian-speaking Switzerland Bärtschi SA Centro Ingegneria Impiantistic Via Baragge 1 c CH - 651 Giubiasco Telefon +41 (0)91 857 7 7 Telefax +41 (0) 91 857 6 78 www.troxhesco.ch info@troxhesco.ch Head office Deutschland TROX GmbH Telefon +49(0)845/0-0 Heinrich-Trox-Platz Telefax+49(0)845/0-65 E-ail trox@trox.de D-47504 Neukirchen-Vluyn www.trox.de Subsidiaries Argentinien TROX Argentina S.A. Australien TROX Australia Pty Ltd Belgien S.A. TROX Belgium N.V. Brasilien TROX do Brasil Ltda. Bulgarien China TROX Air Conditioning Components(Suzhou) Co., Ltd. Dänemark TROX Danmark A/S Deutschland FSL GmbH & Co. KGTROX Deutschland GmbH Frankreich TROX France Sarl Großbritannien TROX UK Ltd. TROX AITCS Ltd. Hongkong TROX Hong Kong Ltd. TROX AITCS Ltd. Indien TROX INDIA PRIVATE LIITED Italien TROX Italia S.p.A. Kroatien alaysia TROX alaysia Sdn. Bhd. Norwegen TROX Auranor Norge AS Österreich Polen Rumänien Russland OOO TROX RUS Schweden TROX Sverige AB Schweiz TROX HESCO Schweiz AG Serbien Spanien TROX España, S.A. Südafrika TROX South Africa (Pty) Ltd Tschechische Republik Ungarn USA TROX USA, Inc. TROX AITCS Ltd. Vereinigte Arabische Emirate TROX iddle East (LLC) Foreign representations Abu Dhabi Ägypten Bosnien-Herzegowina Chile Finnland Griechenland Indonesien Iran Irland Island Israel Jordanien Korea Lettland Libanon Litauen arokko Neuseeland Niederlande Oman Pakistan Philippinen Portugal Saudi Arabien Schweden Simbabwe Slowakische Republik Slowenien Taiwan Thailand Türkei Ukraine Uruguay Venezuela Vietnam Zypern