With the right approach, the heat generated by chillers in an indoor ice rink can be used to melt ice, a dehydration system, or to heat a concrete pad under a layer of ice. In this way, energy can be saved. For the purpose of accumulation and subsequent distribution of thermal energy in the building, a reservoir that accumulates heat can be used. Heat is removed from the chiller condenser by a water cooling circuit, which is connected to the coil of an indirect heating boiler (heat accumulator). The coil heats the water that circulates in the heating circuit. Since the load on the ice can change during the day, heat extraction will occur in different amounts. For efficient transfer of thermal energy from one heat exchanger to another, it is necessary to control the speed of rotation of the pump impeller so that the controlled function is maximum. If the speed is insufficient, then the heat exchange flow will receive less heat. On the contrary, if the drive drives antifreeze too quickly, then the coolant will not have time to heat up. A mathematical model of the system was compiled from a plant condenser and a boiler with heated water, a dependence on the speed of the coolant (antifreeze) and the temperature difference at the inlet and outlet of the accumulator was revealed.
Keywords: heat accumulator, temperature control, shell-and-tube heat exchanger, optimal regulator, freon
This article discusses one of the parts of the development of a device for testing samples of magnetostrictive materials. A study of various designs and an analysis of the sensitivity of the measuring system are presented. The substantiation of the use of a magnetic shunt to increase the sensitivity is given, which is confirmed in field experiments.
Keywords: magnetostrictive materials, basic magnetization curve, magnetic shunt, magnetic flux