12th International Symposium on District Heating and Cooling

The <strong>12th</strong> <strong>International</strong> <strong>Symposium</strong> on District Heating and Cooling,September 5 th to September 7 th , 2010, Tallinn, EstoniaTest results Thermaflex heat loss equipmentIn this paragraph the test results are presented for thetests carried out with the Thermaflex heat lossequipment. For this study four different types of theFlexalen 600 series were tested. The tests for theFlexalen 600 series took place at three differenttemperatures, 60, 70 and 80 °C. The values at lowertemperatures are calculated using the linearizationmethod described in the European standard EN 15632[1]. In the following tables and graphs the test results ofthe Thermaflex heat loss equipment are presented.The power usage during the testing cycle is shown inGraph 2. In this graph the first 40 minutes represent theheating and stabilisation time for the heating probe andinsulation, whereas the last 30 minutes is the actualtest time. Since, as the figure shows, the temperatureis constant, the power usage equals the heat lossthrough the piping system in radial direction during thelast 30 minutes. The results, as given in Table 1, arecalculated by using the mean of the powerconsumption during the last 30 minutes of the heat losstest. The results in Table 1, are also displayed inGraph 1 for the three tested samples.Table 1, Results heat loss equipment for the Flexalen 600productsHeat loss of the Flexalen 600 series in W/m tested onthe Thermaflex heat loss equipmentProduct 40 °C 50 °C 60 °C 70 °C 80 °C50A25 3.6 6.4 9.3 12.0 15.0160A90 6.2 10.1 14.0 17.9 21.8200A110 6.5 12.0 17.5 23.0 28.5Graph 2, Power and temperature of the Thermaflexheating probe.Outcome Competitive products for comparison oftesting method:For the comparison with test institute two, two samplesof competitive products are tested. As these samplesare ST-PUR-PE system, a correction has been madefor using the PB heating probe using the Wallentén [2]method. First the thermal conductivity of the insulationis determent by the use of equation (5), hereafter theheat loss is recalculated without the heating probe,using the temperature of the inner service pipe inequation (6). The results are presented in Table 2 andGraph 3. iT p T c2 probe d 3ln d 2 1 dln2 1 d 6 ln 1 d ln4 st d 1 p d 5 c d 3 Wm K (5)Heat loss [W/m]302010Heat loss results thermaflex heat loss equipment 2 T st T c corrected1 d 2ln 1 dln3 1 d 4 ln st d 1 i d 2 c d 3Where: Wm (6)T p ,T c , T st =Probe, Casing and Steel pipe temperatured 1 to d 6 = inner/outer diameters of service pipe, casingand heatingprobe040 50 60 70 80Temp erature inner service pipe [°C]Flexalen 50A25Flexalen 160A90Flexalen 200A110λ st , λ i , λ c , λ p = heat coefficient of service pipe, insulation,casing and probeΦ probe , Φ corrected =probe power and corrected heat loss.Graph 1, Results heat loss equipment Flexalen 600products.253