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Zbigniew Rymarczyk, Paweł Purgał – The Institute of Heating and Sanitary Technology in Radom Mieczysław Dzierzgowski – The Warsaw University of Technology.

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Presentation on theme: "Zbigniew Rymarczyk, Paweł Purgał – The Institute of Heating and Sanitary Technology in Radom Mieczysław Dzierzgowski – The Warsaw University of Technology."— Presentation transcript:

1 Zbigniew Rymarczyk, Paweł Purgał – The Institute of Heating and Sanitary Technology in Radom Mieczysław Dzierzgowski – The Warsaw University of Technology

2 2 Gable wall of a building large slab system, the 70s (t ex about –2 o C) bad insulation of joints reduced thickness of insulation ceiling roof lack of insulation in the prefabricated wall inacurate placement of insulation material

3 3 Gable walls of buildings large slab system, the 70s (t ex about –2 o C) the wall before warming up the wall after warming up

4 4 Test requirements– building envelopes of light construction, the Scandinavian conditions PN-EN 13 187-2001 standard: Thermal characteristics of buildings – Quality detection of heat faults in building walling – Infrared Method The air temperature outside may change not more then  10 o C in comparison temperature at the beginning of the check for at least 24 hours since the beginning of tests, The difference in air temperature on both sides of the building should not be smaller than 3/U, where U is a theoretical value of coefficient of heat permeability of building element, this difference cannot be smaller than 5º for at least 24 hrs before the beginning of tests and during it It is recommended that the monitored wall surfaces should not be exposed directly to sun radiation for 12 hrs before the beginning of tests, During the check the air temperature outside should not change more than ± 5 º and the temperature inside not more than ± 2º in comparison to appropriate values at the beginning of tests

5 5 Air temperature inside and outside and difference between these two temperatures Temperature of the air -5,00 0,00 5,00 10,00 15,00 20,00 25,00 30,00 35,00 14:1022:55 0:101:252:403:555:106:257:408:55 10:1011:2512:4013:5515:1016:2517:4018:5520:1021:25 time temperature [ o C] tin oC tex oC Dt

6 6 „the air temperature outside may change not more than ± 10º in comparison to the temperature at the beginning of the check for at least 24 hours since the beginning of tests” The minimum temperature of the air outside in the period before the measurements was 1.8º C The maximum temperature of the air outside in the period before the measurements was 10.8ºC The temperature at the beginning of the measurements was 2.8ºC The requirement was fulfilled

7 7 „The difference of air temperature on both sides of the building should not be smaller than 3/U, for at least 24 hrs before the beginning of tests and during it” The designed value of the coefficient of heat permeability = 0.55 W/m²K, The difference between the air temperature inside and outside changed from 20.0ºC to 30.5ºC The difference at the beginning of the test 27,4 o C The requirement was fulfilled

8 8 „It is recommended that the monitored wall surfaces should not be exposed directly to sun radiation for 12 hrs before the beginning of tests ” On the day before the measurement - there was overcast the requirement was fulfilled

9 9 „During the check the air temperature outside should not change more than ± 5 º and the temperature inside not more than ± 2º in comparison to appropriate values at the beginning of tests ” The air temperature during the check 0,00 5,00 10,00 15,00 20,00 25,00 30,00 35,00 22:1022:4023:1023:40 0:100:401:101:402:102:403:103:404:104:405:105:406:10 time temperature [ o C] tin oC tex oC Serie10

10 10 „During the check the air temperature outside should not change more than ± 5 º and the temperature inside not more than ± 2º in comparison to appropriate values at the beginning of tests ” The air temperature outside changed from 1.8ºC to 2.8ºC The air temperature inside changed from 29.8ºC to 30.2ºC the requirement was fulfilled

11 11 The device enabling the determination of heat resistance of building envelopes

12 12 The basic technical data of the device The frequency range of recording to memory – from 4 sec to 90 min The maximum number of recorded measurements – 24 500 Channels 1 : 5 – heat sensors shaped as measurement plates of 120 mm x 120 mm Channel 8 – converter of relative humidity, the measurement range 0...100% RH Channels 9…18 – temperature sensors

13 13 The results of the device check Number of chanel UnitValueValue of reference Measured value k1W/m 2 10 mV122,80 W/m 2 122,9 W/m 2 k2k2W/m 2 10 mV115,10 W/m 2 115,8 W/m 2 k3k3W/m 2 10 mV105,90 W/m 2 105,5 W/m 2 k4k4W/m 2 10 mV113,90 W/m 2 113,6 W/m 2 k5k5W/m 2 10 mV105,00 W/m 2 105,3 W/m 2 k8k8%12 mA50,00 %49,8 % k9 oCoC22 o C22,0 o C22,04 o C k10 oCoC22 o C22,0 o C22,05 o C k11 oCoC22 o C22,0 o C22,03 o C k12 oCoC22 o C22,0 o C22,05 o C k13 oCoC22 o C22,0 o C22,04 o C k14 oCoC22 o C22,0 o C22,05 o C k15 oCoC22 o C22,0 o C22,05 o C k16 oCoC22 o C22,0 o C22,05 o C k17 oCoC0 o C0,0 o C-0,07 o C k18 oCoC0 o C0,0 o C-0,07 o C

14 14 A photo and thermograms of a part of the wall with fitted sensors monitoring the heat flux density and the temperature on the inside U3 U1 U4U5

15 15 A photo and thermogram a part of the wall on the outside

16 16 The changes of the heat flux density during the measurement Changes heat flux density 0 5 10 15 20 25 30 35 40 45 50 22:1022:4023:1023:40 0:100:401:101:402:102:403:103:404:104:405:10 Time Heat flux density [W/m 2 ] q1 q3 q4 q5

17 17 Thermal resistance of the parts of the wall 1,60 1,55 0,61 1,65 1,63 0,67 1,59 0,64 1,62 0,00 0,20 0,40 0,60 0,80 1,00 1,20 1,40 1,60 1,80 Place 1Place 4place 5 Thermal resistance (m 2. K)/W Rmin Rmax Rśr

18 18 Deviation of heat resistance from an average value in the place of measurement -1,40 -2,40 -3,20 1,50 2,10 4,40 -4,00 -3,00 -2,00 -1,00 0,00 1,00 2,00 3,00 4,00 5,00 place 1place 4place 5 Deviatin of heat resistance [%] Min. value. Maks. value

19 19 Final remarks as regards the assessment of thermal insulation: The research into thermal insulation of an object have practical significance for new erected and older buildings thermally modernized It is recommended to combine classical measurement methods of the heat flux density and temperature with the thermography

20 20 Is it worth measuring the thermal resistance of building envelopes in real conditions? In the view of the C1152 standard: ”Determining heat resistance of building partitions on the basis of measurements conducted in situ” the answer is positive: For newly erected buildings — „the knowledge of thermal resistance of new buildings is important to determine whether the quality of constructin satisfies criteria set by the designer, by the owner, or by regulatory agency. Differences in quality of materials or workmanship may cause building components not to achieve design performance”

21 21 Is it worth measuring the thermal resistance of building envelopes in real conditions? In the view of the C1152 standard: ”Determining heat resistance of building partitions on the basis of measurements conducted in situ” the answer is positive: For the existing buildings – „knowledge of thermal resistance is important to the owners of older buildings to determine wheter the buildings should receive insulation or other energy – conserving improvements. Inadequate knowledge of the thermal properties of materials or heat flow paths within the construction or degradation of materials may cause inaccurate assumptions in calculations that use published date”

22 22 The use of thermography in the diagnosis of the central heating installation Determining the flow of water mass Other applications (pollution, the air infection, hydraulic maladjustment, leak of heating element from the installation)

23 23 Application of thermography in the diagnosis of the central heating installation The Water Mass Jet 1. The mathematical calibration of a model of heat exchange in the arrangement of “a heater – a heated room” on the basis of heat and thermographic research, at the stand for the research into heaters with an open type of chamber at The Warsaw University of Technology, including a calculation programme (radiator T1, 10 units) 2. Conducting the verification tests of heat and thermographic research of a heater at the stand for heat research into heaters with a closed type of chamber (radiator T1, 8 units)

24 24 3. Determining heat power of a heater and the water mass with the use of thermography and a computer software for a heater on the basis of the data acquired in point 2 4. Comparing the obtained results in accordance to points 2 and 3 Application of thermography in the diagnosis of the central heating installation The Water Mass Jet continued

25 25 T-1 Heater – a photograph and construction

26 26 Technical data of T-1 heater Total height in mm588 Fitting height between axis joints in mm 500 Width of a heater unit in mm79,7 Building depth in mm140 Outside surface area of 1 unit in m² 0,24 Water capacity of one cell in dm³1,18 Nominal mass of one cell in kilos5,70 Number of units in the examined heater 8

27 27 The computer software designed at the Warsaw University of Technology makes it possible to determine : Temperature distribution along its height, Heat power, [W] Average temperature of the surface, [ o C]

28 28 Temperature of supply, return, air and mass jet in the function of time for a T1 heater in a chamber of an open type 0,010 0,015 0,020 0,025 0,030 0,035 M [kg/s] t1 t2 ti M

29 29 Thermograms of T1 heater a) flow 0.01409kg/sec b) flow 0.00638 kg/sec in an open type of chamber

30 30 The test stand with a closed type of chamber – The Institute of Heating and Sanitary Technology – Radom Stand for research into heaters compatible with PN-EN 442-2:1999 standard The Quality Assurance system in the laboratory in compliance with PN-EN ISO/IEC 17025:2001 standard “ General requirements as regards competence of research and standardization laboratories”.

31 31 The chart of a research stand: 1 – circulation pump, 2 – tank, 3 – electric boiler, 4 – mixing device, 5 – overflow, 6 - valve, 7 –tested heater, 8 – flow regulating valve, 9 – heat exchanger, 10 – valve, 11 – valve, 12 – points of temperature measurements, 13 – measurement vessel

32 32 A thermogram obtained at the stand for heater tests with a closed chamber and the temperature profile obtained experimentally and on the basis of a mathematical model

33 33 Conclusion Divergence between the water jet obtained on the basis of heat tests and the jet of mass obtained on the basis of a mathematical model and thermovision tests amounted to 4%

34 34 Heating – the water mass jet – real conditions 0,00485 kg/s – beafore cleaning0,0435kg/s – after cleaning 1 2 3 4 IR - I0000000.004 97-02-05 20:57:48 20,0 50,0°C 20 25 30 35 40 45 50 1 2 3 4 IR - I0000000.054 97-01-09 22:18:02 20,0 50,0°C 20 25 30 35 40 45 50

35 35 51,6 o C40,9 o C Heating – diagnostic of the central heating components - pollution

36 36 Heating – temperature distribution on the heater surface in the conditions of air infection of the central heating installation Heater with air infecton Heater after the process of air removal

37 37 Heating – the distribution of temperature occurs in the case of hydraulic deregulation

38 38 Heating- the central heating lines cause local increase in the surface temperature of the floor

39 39 Heating – leakage of the central heating components out flow from the central heating installation

40 40 Final conclusion: Simultaneously with insulation tests of building envelopes the theromgraphic method may be applied in heating for :  Estimating the water mass jet  Preliminary diagnosis of units of the central heating installation ( air infection, pollution, hydraulic deregulation, detection of installation leakage)


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