Success story of a quiet condensing unit. Silensys by Tecumseh

Transcription

1 Success story of a quiet condensing unit Silensys by Tecumseh

2 Chillventa 2012 Noise reduction approach of cold applications Starting point of Silensys launching Noise source of a refrigerating application Curative standard solutions Even greater noise reduction with the Silensys Perspectives Loop system, production control Conclusions

3 Starting point of Silensys launching Where it all started Market investigation and his constraints

4 Starting point of Silensys launching A nationwide quantitative survey: 250 refrigerating technicians, 90 questions, in June1998 French and European qualitative surveys: PACA, Rhône-Alpes, Alsace, Ile de France, Great Britain, Germany 130 refrigerating technicians, meetings (more than 100 hours) Test sites

5 Starting point of Silensys launching Installer practices inside Installer preferences inside outside outside With 30% under cover and 30% housed but in half of the cases, unsatisfactory installations Have you ever experienced noise problems? No Yes 12% of Condensing Units were installed with acoustic treatment.

6 Starting point of Silensys launching The constraints linked to urbanism noise space problem esthetic problems

7 Starting point of Silensys launching There is a need of outside condensing unit in commercial refrigeration The core range of the applications is 3,5 to 6 kw It must be adapted to urban constraints: Silent Aesthetic Protected

8 Chillventa 2012 Noise reduction approach of cold applications Starting point of Silensys launching Noise source of a refrigerating application Curative standard solutions Even greater noise reduction with the Silensys Perspectives Loop system, production control Conclusions

9 Noise source of a refrigerating application

10 Noise source of a refrigerating application The total noise is the sum of the noise emission from two leading sources: Compressor + Fan

11 Chillventa 2012 Noise reduction approach of cold applications Starting point of Silensys launching Noise source of a refrigerating application Curative standard solutions Even greater noise reduction with the Silensys Perspectives Loop system, production control Conclusions

12 Curative standard solutions Piston compressor Noise reduction

13 Curative standard solutions Reciprocating compressor structure Electrical motor Muffler Internal spring mounting Shock loop Compression kit

14 Curative standard solutions Noise figure Transfer Path pulse flow rate pressure mechanical interactions catching up clearance impacts valves / seats stops strengths of inertia unbalance compressing motor magnetic force Flow rate mass immediate exhaust fluid head / valve sound Shock mechanism impact energy M excentric + a.m solid rod instantaneous torque M piston + b.m solid rod compression kit Shock fluid transfer path suction line Oil transfer path Internal spring mounting Shock loop Compressor shell (solid crankcase and elasticity) Transfer to the application - indirect ray Fluid Suction tube and shock Silentblocs Indirect emission Struct

15 Curative standard solutions Noise reduction of reciprocating compressors MUFFLER SHOCK LOOP HOUSING

16 Curative standard solutions Noise reduction of reciprocating compressors VALVE INTERNAL SPRING MOUNTING Decoupling of high frequencies modes by an interface spring / plastic crankcase Friction damping of spring modes

17 Curative standard solutions Noise reduction of reciprocating compressors The limits of this process A long response time and heavy investment We work only on one of the two sources and not on other possible improvements like aesthetic, protection... Noise reduction of compressors is necessary but it is not a complete solution for solving this problem

18 Chillventa 2012 Noise reduction approach of cold applications Starting point of Silensys launching Noise source of a refrigerating application Curative standard solutions Even greater noise reduction with the Silensys Perspectives Loop system, production control Conclusions

19 Even greater noise reduction with the Silensys The solutions applied on Silensys Aeraulic: Augmented size of condenser Improved fan performance (pressure drop reduction, blades) Reduced fan speed Compressor cover

20 Even greater noise reduction with the Silensys solutions applied on Silensys

21 Even greater noise reduction with the Silensys Silensys Condenser Fan Discharge tube Cover support & schroud Suction tube Compressor Silentblocs

22 Even greater noise reduction with the Silensys Condensing unit Condenser Discharge tube support and ferrule Suction tube Compressor Silentblocs

23 Even greater noise reduction with the Silensys The solutions applied on Silensys Work on fan Condenser size => reduction of the fan speed Shape of the blades Links with the other parts of the application

24 Even greater noise reduction with the Silensys The solutions applied on Silensys With the aeraulic treatment, compressor noise becomes dominant in some frequencies It is essential to treat the second source, the compressor

25 Even greater noise reduction with the Silensys The solutions applied on Silensys The compressor cover contributes to a significant improvement

26 Even greater noise reduction with the Silensys The solutions applied on Silensys Contributions on Silensys Compressor and fan have contributions relatively balanced The cover and the choice of fan are well suited

27 Even greater noise reduction with the Silensys The solutions applied on Silensys Sound power comparison - Silensys - STD Group Decibel d Or to 12 db noise reduction compared to a standard group

28 Even greater noise reduction with the Silensys The solutions applied on Silensys Cover treatment Specificity: ensured a good air flow for refreshing the compressor Pay attention to acoustic jacket! OPENING OPENING

29 Chillventa 2012 Noise reduction approach of cold applications Starting point of Silensys launching Noise source of a refrigerating application Curative standard solutions Even greater noise reduction with the Silensys Perspectives Loop system, production control Conclusions

30 Perspectives the solutions applied on Silensys In the future?

31 Perspectives The solutions for V3 Fan blades Design to optimize acoustics Air duct Optimum acoustics + optimum airflow Lateral door Double plastic skin to limitate sound transmission Global stiffness Metal frame around door to reduce solid transmission Discharge side HP line muffler to minimize pressure pulsations Air circulation Foam under top encapsulate noise Piping Specific design to reduce and absorb vibrations

32 Perspectives Solutions for the future Known solutions: Variable speed: BLDC instead of asynchronous + dimmer Improving the fan efficiency : blade design, shape of the shroud Improvement of cover: the most transparent walls are identified Treatment of vibration transfers: -Tubes (vibration and pressure pulses) - Housings and fan shroud Work on the compressor Search: Condenser emission: CETIM-CETIAT thesis under collaborative studies Complete modeling application with CETIM

33 Perspectives Transfer of vibration through the tubes V2 standard V3 proto V3 PS with muffler V3 PS without muffler V2 standard V3 PS with muffler

34 Perspectives Emission structures Velocity quadratic normal force Ty=1 on pts 1

35 Perspectives Emission structures Modal analysis and frame Silensys response

36 Chillventa 2012 Noise reduction approach of cold applications Starting point of Silensys launching Noise source of a refrigerating application Curative standard solutions Even greater noise reduction with the Silensys Perspectives Loop system, production control Conclusions

37 Loop system, production control Importance of tests Looping approach

38 Loop system, production control Importance of tests make the diagnosis of existing evaluate the design improvement establish data sheets master the processus - quality control by sampling - measure on production line Design phase Assist the integration Inform Production Phase

39 Loop system, production control Test chamber for measuring power soundproof room reverberant room

40 Loop system, production control Certification Cofrac accredited laboratory - Acoustic, cooling performance and electrical safety - Recognition as a reference laboratory according to ISO 3743 and ISO Annual Audit. Certification NF 402 Acoustic Performance - Compliance with ISO4871 for acoustic & performances evaluated according the NF C / 32 C ambient / 20 C suction gas / subcooling 3K for LBP applications +5 C / 32 C ambient / 20 C suction gas / subcooling 3K for HBP applications

41 Loop system, production control Certification 3 levels of precision control ISO 3747/3746 expertise ISO 3743/3744 laboratory ISO 3741/3745 Measurement tolerances standards respected by the acoustic laboratory of Tecumseh reverberant fields free fields

42 Loop system, production control Acoustic information Sound power - A Indice noise rating Octave band spectrum Acoustic pressure level

43 Loop system, production control Data base Systematic measurement of acoustic power for all products developed in their different design phases Quality control on bestsellers 255 fields filled in automatically (conditions of pressure, temperatures, performances, input power...) 45,000 compressors measured since 1995

44 Loop system, production control Data base Example of the database following product evolutions based on improvements importance dispersions => analyze population

45 Loop system, production control Specific tests unit improvement Intensimetry measurement

46 Loop system, production control Mastery of processes Systematic control at the end of assemble line Quick Test Performed in air Evaluation of a accelerometer level (vibration) 3 checkpoints at the end of the assembly line Daily collection on assembly line Test performance Implementation extrapolation acceleration - acoustic power (CETIM-CETIAT) Monthly taking Quality control Measurement of sound power in our laboratory. Laser - measurement Doppler effect - towards checkpoint Flux - compressor production line

47 Chillventa 2012 Noise reduction approach of cold applications Starting point of Silensys launching Noise source of a refrigerating application Curative standard solutions Even greater noise reduction with the Silensys Perspectives Loop system, production control Conclusions

48 Conclusions There is a silent market To respond to this market, we need to integrate it into a corporate culture of acoustics: simulations, metrology practices => men and means Importance of collaborations with external expertises Built-in earlier in the design, Measure progress on prototypes and products of sets per reliable and recognized test methods Communicate the acoustic performance Data sheets (for engineering) Label (for many of our customers)

49 Thank you for your attention