Acoustic behaviour and placement of heat pumps - EHPA

Acoustic behaviour and
placement of heat pumps
THE ESSENCE OF HEAT PUMPS SERIES
The perception of sound and heat pumps
Online, 02.09.2020

Christoph Reichl, Johann Emhofer, G. Drexler-Schmid, Peter Wimberger,
  Felix Linhardt, Brigitte Blank-Landeshammer, Andreas Sporr, Thomas Fleckl

CONTENT

1 Motivation
2 Acoustic behavior of heat pumps
  Measurement techniques and results
3 Placement assistance for heat pumps
  HVAC Positioner: current implementation and development
4 Summary

MOTIVATION
"Especially Air-to-Water Heat
Pumps play an important role
to reach the climate goals."
"Acoustic Emissions have
the potential to slow down
the necessary market growth."

01.09.2020                      © DR DRUCK GmbH
                                             3

2 ACOUSTIC BEHAVIOUR OF HEAT PUMPS
Measurement techniques and results

ACOUSTIC ROUND ROBIN TESTS // ANNEX 51

                    •   3 heat pumps on tour through Europe:
                          • Exhaust-air Heat Pump Water Heater (HPWH)
                          • Air-to-water Heat Pump
                          • Air-to-air Heat Pump
                    •   Measurements using various
                        experimental techniques at
                          • CETIAT, France
                          • DTI, Denmark
                          • Fraunhofer ISE & IBP, Germany
                          • Polimi, Italy
                          • RI.SE, Sweden
                          • AIT, TU Wien, Austria

ACOUSTIC ROUND ROBIN TESTS // ANNEX 51

       Examples of heat pump installation in a reverberation room (left) and in
       climatic chambers (middle and right). A setup with microphone array is
       shown in the right picture. Source: CETIAT, France (left), ISE, Germany
       (middle) and AIT, Austria (right).

SOUND POWER LEVEL (FREQUENCY RESOLVED)

           5 dB(A)

       Frequency spectrum of the A-weighted sound power level for standard
       conditions according to EN 14511 (#1) with the results of 6 laboratories
       (source: CETIAT, France)

DIRECTVITY (FREQUENCY RESOLVED)

  Polar pattern of the total A-weighted sound pressure level measured at a height of
  75 cm (left) and the polar pattern for the different A-weighted octave bands (right)
  (source: AIT, Austria)

ACOUSTIC DOME / TRANSIENT DATA

ACOUSTIC DOME / TRANSIENT DATA

ACOUSTIC DOME / CYCLE DATA

ACOUSTIC DOME / FROSTING

        Time [minutes]

                         frequency 24th octave band

ACOUSTIC DOME / DEFROSTING

 Sound power level time series & frequency spectra

ACOUSTIC DOME / DEFROSTING

 Detailed frequency spectra (waterfall plot)

3 PLACEMENT ASSISTANT FOR HEAT PUMPS
HVAC Positioner: current implementation and development

HVAC POSITIONER DEVELOPMENT

           (a)                       (b)                        (c)                       (d)

 The development of the app during the RAARA project. (a) shows the live image of the mobile app
 with inserted sound source. (b) shows the identified ground and the unidentified other visible
 elements. In (c) a wall was inserted to equalize the unidentified house wall. (d) shows a part of the
 functions implemented at the end of the project.

HVAC POSITIONER // REFLECTIONS

 Calculation of sound propagation with different options regarding the surrounding environment: (a)
 free field with floor plane; (b) along a wall; (c) in a corner; (d) automatically detect the surrounding
 geometry for the simulation

AUGMENTED REALITY / 5 CHANNEL SYSTEM

The laboratory heat pump prototype SilentAirHP is virtually faded into a real world and the sound
emissions are made visible (left); 5-channel measuring system for generating the database for the
aurealization of the heat pumps in the Augmentend Reality App.

INTENSITY PROBE MEASUREMENT
                                                                            Total

             Third octave band frequency [Hz]

                                                Sound power level [dB(A)]
 Intensity measurement using the scanning technique:
 A-weighted sound power level in dBA (EN 14511, A7W35)

SOUND PRESSURE LEVEL CALCULATION

Visualization of the directivity aurealisation technique: (a) the red box represents the sound emitting
HVAC component (e.g. heat pump); (b) the acoustic pressure is recorded in a specific distance to the
emitting surfaces at 5 locations – a measurement surface is formed; (c) rays are generated
connecting the emitter’s corners with the corners of the measurement surface; (d) parts of the planes
stretched by these rays intersected with a sphere; (e) final visualization of the 5 parts of the half-
sphere attributed to the 5 microphone measurement positions.

HVAC POSITIONER APP ON THE WEB
APP for optical and acoustic positioning of heating and cooling devices

Heat pumps are the first choice, if it concerns to bring heating cost saving and environmental-careful heat production
together. However their acquisition is a long-term decision and requires exact planning. The HVAC Positioner is the first
and only App that uses augmented reality to place a heat pump in a real environment. The implemented real-time sound
propagation calculation allows to position the system (heat pump or refrigeration system) perfectly according to current
regulations and personal preferences. The AIT Austrian Institute of Technology has developed a method to minimize noise
emissions of the population in urban areas. These methods allow a simple, intuitive and at the same time precise handling
of noise emissions and are used in the APP of the HVAC Positioner.
The advantages of the HVAC Positioner at a glance:
•   Integration of the heat pump / cooling unit in any environment
•   The noise development can be displayed visually
•   Ongoing development of the application
•   Continuous updating of the database and device types
•   Available in iOS and Playstore - but the end device (tablet, cell phone) must support
    augmented reality

APP in Playstore: HVAC Positioner
APP in iOS store: iOS HVAC Positioner

4 SUMMARY

SUMMARY AND OUTLOOK
 •   Innovative measurement techniques allow for time-,
                                                               CETIAT, FR
     space- and frequency resolved analysis of emissions
 •   Heat pump perception is not only a matter of dB(A) –
     frequency- and time-dependence need to be
     considered
 •   Much has been done by manufactures – correct
     installation & placment is mandatory!
 •   HVAC Positioner App allows for virtually placing heat        AIT, AT
     pumps in real environment and calculation and
     visualizion of sound pressure levels
 •   App is constantly updated: in the next step, reflection
     and absoprtion on/at virtual and real faces as well as
     aurealization will be included

ACKNOWLEDGEMENTS
The work on “IEA HPT Annex 51” is financially supported within the framework of the “IEA
Research Cooperation”, the project "SilentAirHP" within the framework of the "Klima Energy
Fonds" on behalf of the “Austrian Federal Ministry for Transport, Innovation and Technology”.

THANK YOU!
Christoph Reichl for the
Annex 51 & AIT team

02.09.2020