А.V. Khimenko, D.А. Tikhomirov, S.S. Trunov, A.V. Kuzmichev
An urgent issue for agriculture, rural settlements, and remote settlements is the use of efficient decentralized heat supply systems. One of the most effective solutions to this problem is the transition to electric heat storage heating systems. The main advantage of such heating systems is that, with their mass introduction, they can act as consumers-load regulators of the Unified Energy System of Russia at night, when there is a significant decline in electricity consumption. Nighttime dips in the load schedule of the power system lead to additional losses in the power grids, overconsumption of fuel at the thermal power plants (TPPs) and combined thermal and power plants (CTPPs) and reducing their efficiency associated with a decrease in the volume of electricity generation at TPPs and CTPPs. The economic incentive for the introduction of heat storage heating systems is the presence of reduced tariffs for electricity consumption in the period from 23.00 to 07.00 (night zone). Electric heat storage heating systems can also be effectively used in combination with power plants based on renewable energy sources (wind-solar stations).
Experimental studies of the thermal characteristics of heat storage elements of electric thermal storage (ETS) of a dynamic type with controlled heat transfer have been carried out.
At the first stage, studies was carried out the thermal characteristics of heat storage elements made of magnesite with slit-shaped air channels measuring 0,19*0,02 m and a total weight of 62,5 kg were studied, and at the second stage – heat storage elements made of chamotte with two round-shaped channels (d = 0,044 m) and a total weight of 58 kg. Temperatures were measured by primary temperature converters: chromel-alumel (ChA) thermocouples in a ceramic shell and chromel-copel (ChC) thermocouples. In areas with high temperatures, ChA thermocouples were placed in a heat-resistant fabric cover. Thermocouples ChC were used to measure the air temperature at the outlet of the ETS, the surface temperature of the ETS body and the temperature of the thermal insulation.
As a result of experimental studies were obtained: 1. The temperature change walls of the air channels of the heat storage elements with slit-shaped and round-shaped channels made of magnesite and chamotte in lower and upper zones in the modes of charging and heat output of ETS; 2. The temperature change of the heated air in the channels of heat storage elements with channels of slit-shaped and round-shaped channels made of magnesite and chamotte in lower and upper zones in the modes of charging and heat output of ETS; 3. The temperature change of the thermal insulation in lower and upper zones of ETS; 4. The temperature change on the surface of the housing and the temperature change of the heated air at the outlet of ETS.
To increase the heating rate of heat-storage elements made of chamotte, at the second stage of the experiment, metal inserts in the form of steel plates 2 mm thick were used, which were placed between the heat-storage elements. As a result, the values of the air channels wall temperature at the end of the charging mode of ETS increased by an average of 50 °C compared to the option when steel plates were not used .
On the basis of the obtained experimental data, the dynamics of the temperature change of heat storage elements ETS from magnesite and chamotte with slit-shaped and round-shaped channels respectively and the temperature change of heated air in the channels were analyzed. The rate of heating and cooling of heat storage elements made of chamotte and magnesite has been calculated . The conclusion was made about the efficiency of using heat storage elements made of chamotte with two round-shaped channels in ETS.
1. Khimenko А.V. Calculation and experimental study of thermal processes in solid heat storage material with high heat storage properties // NTU "KhPI" Bulletin: Power and heat engineering processes and equipment. – Kh.: NTU "KhPI", 2016. – №10 (1182). – P. 44-49. doi:10.20998/2078-774X.2016.10.06.
2. Khimenko А.V. Evaluation of the efficiency of the heat output by heat storage elements of the electric thermal storage // Power engineering: economics, technique, ecology. – 2017. – №4. – P. 83-94. doi: 10.20535/1813-5420.4.2017.127551.
|Publication||IOP Conference Series: Earth and Environmental Science|
|Affiliation of speaker||Federal State Budgetary Scientific Institution "Federal Scientific Agroengineering Center VIM, Moscow, Russian Federation|
|Position of speaker||Senior researcher|