The Congress Programme
How to optimize heat pump testing with closed loop design 
The use of heat pumps is gaining ground in the market. In contrast to conventional heating systems, the energy generated in heat pumps is emission-free. In addition, when designing and purchasing heat pumps, attention must be paid to energy-efficient operation, which is defined as a decisive quality criterion. This means that heat pump manufacturers are bounded by specific norms (e.g. DIN EN ISO 14511) in order to ensure the specified standards and at the same time to remain competitive. While the development of heat pumps, it is necessary to ensure an optimal simulation of the external installation of heat pumps in order to be able to reproduce the real operating conditions. Current test systems on the market, which are used to test e.g. air / water heat pumps, are climate chambers with a cooling, heating and humidification unit attached to the roof. The disadvantage of this concept is that in the cube-like space no homogeneous temperature and humidity distribution can be adjusted. Based on testing metrology of the automotive industry, EP-E developed a concept in which the air flows in a closed loop (loop design). The air is blown into the chamber and out of the chamber via a flow straightener. The temperature control (cooling, heating) and humidification take place outside the chamber. In addition, it is possible to set and vary the air flow in the loop according to standard conditions. The result of this concept is a very excellent homogeneous temperature and humidity distribution. Very fast readjustment times are achieved by means of the upstream mixture and the control of the tempering water of the air heat exchanger. As a result, the defrosting of the DUT can be readjusted more realistically and, in addition, new test points can be approached more quickly. Also, non-standard climate points (e.g. temperatures including humidity control) can be safely controlled far below the lowest norm-point. If the test bench and the DUT are aligned accordingly, short-circuits in the temperature measurement of the air will be avoided, also the measurement accuracy and the reproducibility of the measurements will be higher. When using several climate chambers or pipe systems including the same concept, different climatic conditions can be simulated. Additional conditioning, e.g. the regulation of a certain CO2 concentration or the adjustment of different pressure ranges (e.g. wind loads) can also be integrated.
--- Date: 23.10.2019 Time: 8:55 - 9:20 Location: Hall Brüssel, NCC Mitte