Thermo-Plus Hot-Water Piglet-Heating Plates

Transcription

1 REVENTA Kunststoffverarbeitung GmbH & Co. KG Thermo-Plus Hot-Water Piglet-Heating Plates Heat distribution and heat output DLG Test Report 6079 F Brief description Applicant REVENTA Kunststoffverarbeitung GmbH & Co. KG Im Gewerbegebiet 3 D Horstmar Tel.: +49 (0) Fax: +49 (0) Contact person: Mr Reutter t.reutter@reventa.de The tested Thermo-Plus pigletheating plates are hot-water heating plates made of polyethylene in various lengths and widths, with insulation under the plate. The flow of hot water is fed into the plate s interior through a stainless steel pipe and thereby heats the water that fills the space inside the plate, acting as a heat transfer medium to heat the plate s surface. On the underside of the plate, there is thermal insulation with a thickness of approx. 15 mm. The test included the following heating plate models: Model 400 x 1,200 mm Model 500 x 1,200 mm Model 400 x 1,600 mm Model 500 x 1,600 mm DLG e.v. Test Center Technology and Farm Inputs DLG Test Report 6079 F Page 1 of 6

2 Technical Data (Measured Values) Thermo-Plus universal hot-water plates with insulation Plate size [mm] 400 x 1, x 1, x 1, x 1,600 Materials HDPE HDPE HDPE HDPE Plate length [mm] 1,190 1,190 1,590 1,590 Plate width [mm] Plate thickness [mm] Insulating material [mm] Unladen weight [kg] Water filling [litres] approx approx approx. 18 approx. 23 Test Results and Individual Evaluations Thermo-Plus universal hot-water plates with insulation Plate size [mm] 400 x 1, x 1, x 1, x 1,600 Ideal inlet temperature [ C] Evaluation Test results at ideal inlet temperature (50 C) and a water throughput of 500 l/h Proportion of lying area with advantageous temperatures C [%] Evaluation Proportion of lying area with optimum temperatures C [%] Evaluation Mean surface temperature [ C] Evaluation Coefficient of variation CV [%] 2.7 % 3.5 % 3.5 % 3.6 % Evaluation Heat output [kw/m²] Evaluation + Evaluation range: ++ / + / / / ( = standard); for CV: + / / ( = standard) DLG Test Report 6079 F Page 2 of 6

3 Test Heat Distribution and Heat Output 42.9 C 42.5 C 40.0 C 37.5 C 35.0 C 32.5 C 30.0 C 27.5 C 25.0 C 22.5 C 20.0 C 19.0 C Figure 2: Thermal image for the Thermo-Plus 500 x 1,200 mm with insulation at an inlet temperature of 50 C (the green area represents the proportion of lying area with optimum temperatures of C) The best results in the test were obtained with the 400 x 1,600 mm plate size. Increasing the inlet temperature to above 50 C did not further maximise the proportional areas in any of the plate models. Temperatures of around 40 C on the piglet-nest plate are considered the ideal ambient temperature for piglets in the first days of life. All of the plates achieved this desirable mean surface temperature of 40 C. The coefficient of variation (CV) of less than 5 % indicates good uniform temperature distribution over the plate. Excess scattering of the surface temperatures is to be avoided so that an optimum lying area can be provided even for lower-ranking animals. The heat distribution and heat output were tested in the laboratory without animals at a room air temperature of 20 C ± 2K without exposure to direct sunlight. The measurements were performed on individual plates. The water throughput was kept constant at 500 l/h ± 5 %. The determined values relate exclusively to the stable state of the plate following the respective heating phase. Various inlet temperatures were investigated in order to determine the optimum inlet temperature that gives the maximum proportion of lying area with optimum temperatures. Each selected inlet temperature was repeated on three identical plates in order to rule out the effect of potential variations between plates. Heat distribution (individual plate) The heat distribution was recorded using thermograms from a thermal imaging camera and analysed using software. Each thermogram records between 5,000 and 8,000 surface temperatures, from which it is easy to derive a mean value over the plate. Before the measurements were taken, a value of ε = 0.94 was determined for the emission factor applicable to the plate and a value of RTC = 20 C was determined for the corresponding reflected ambient temperature. At an inlet temperature of 50 C and a water throughput of 500 l/h, all of the plate sizes delivered the same maximum proportions of lying area with optimum temperatures (39 41 C). In all of the tested plates, more than 90 % of the surface temperatures were in the advantageous range between 37 and 43 C. The thermogram (Figure 2) illustrates the temperature data and shows the plate with the best results with regard to the proportion of lying area with optimum temperatures of C. As with all commercially available water-filled plates, a certain proportion of air in the plate is unavoidable. However, all users should ensure that the plate is filled with water as well as possible, as this strongly influences the heat distribution. Evaluation of heat distribution* at optimum inlet temperature of 50 C Lying area with advantageous temperatures + + Lying area with optimum temperatures x 1,600 mm with insulation + + Mean temperature on the plate + + Coefficient of variation (CV) = uniform temperature distribution + * Evaluation range: ++ / + / / / ( = standard) DLG Test Report 6079 F Page 3 of 6

4 Table 1: Heat distribution individual results for Thermo-Plus universal Size Inlet temperature Surface T, mean Standard deviation Coefficient of variation CV* Surface T, max. Proportion of lying area with optimum temperatures C [%] Proportion of lying area with advantageous temperatures C [%] [ C] [ C] s [%] [ C] Length: 1,200 mm 400 x 1, x 1, x 1, Evaluation x 1, x 1, x 1, x 1, Evaluation x 1, Length: 1,600 mm 400 x 1, x 1, x 1, Evaluation x 1, x 1, x 1, x 1, x 1, Evaluation x 1, * CV = coefficient of variation [%] = (standard deviation / mean temperature)*100 DLG Test Report 6079 F Page 4 of 6

5 Heat output (individual plate) The heat output Q was determined by continual measurement of a plate s inlet and outlet temperature, as well as the current volumetric flow rate of the heating medium, water. All measurements were taken in the laboratory without animals at a room air temperature of 20 C ± 2K and a water throughput of 500 l/h ± 5 %. Each setting was repeated on three identical plates. The determined values indicate the heat output of an individual plate in the stable state. During the heating-up phase, higher values occur for short periods of time. Losses occurring in practice via the water pipe or hot-water supply are not taken into account only the output of the individual plate is investigated. Heat emissions from the animals body heat were not simulated. The measurements were repeated at different inlet temperatures to allow better characterisation of the plates behaviour. To allow better comparison of the data, the evaluations relate to the heat output in kw per m² of plate surface and to a water throughput of exactly 500 l per hour. At an inlet temperature of 50 C and a water throughput of 500 l/h that lead to an optimum heat distribution, mean heat outputs of the plates of between 230 and 330 W were needed. Due to thermo dyna mics, the larger but otherwise identical plates exhibit a somewhat higher energy demand in order to produce the same surface temperatures. Per square metre of heated area, the smaller plates perform slightly worse. At 0.41 kw/m², the most-favourable result was achieved by the Thermo- Plus 500 x 1,600 mm with insulation. Evaluation* Heat output 500 x 1,600 mm with insulation + Table 2: Heat output at 500 l/h Thermo-Plus universal Inlet temperature [ C] x 1,200 mm Heat output Q [kw] Specific heat output Q [kw/m²] Evaluation 500 x 1,200 mm Heat output Q [kw] Specific heat output Q [kw/m²] Evaluation 400 x 1,600 mm Heat output Q [kw] Specific heat output Q [kw/m²] Evaluation 500 x 1,600 mm Heat output Q [kw] Specific heat output Q [kw/m²] Evaluation + * Evaluation range: ++ / + / / / ( = standard) DLG Test Report 6079 F Page 5 of 6

6 Test The DLG FokusTest included measurements on test rigs at the DLG Test Center. The heat output and heat distribution were investigated. Other criteria were not tested. Test execution DLG e.v., Test Center Technology and Farm Inputs, Max-Eyth-Weg 1, Groß-Umstadt Reporting engineer Dipl.-Ing. Iris Beckert Quality controller Dipl-Ing. Winfried Gramatte May 2015 DLG DLG e.v. Test Center Technology and Farm Inputs Max-Eyth-Weg 1, D Groß-Umstadt, Tel.: , Fax: Internet: Download all DLG test reports free of charge at: DLG Test Report 6079 F Page 6 of 6