Refrigeration and Air Conditioning
The calculation of energy consumption for heating and cooling of buildings is carried out according to the methods prescribed by state standards and other normative documents. The values of the annual costs of thermal and electric energy depend on the initial conditions characterizing the object (in this case, the public building), the mode of its operation and the climatological factors inherent in the geographical region in which the building is located. Analysis of regulatory documents allowed to form a working algorithm for performing settlement operations. A calculation program has been developed that corresponds to the developed algorithm, and a database management system. This allowed us to determine the potential (expected) energy consumption of the building for the heating and cooling periods. A detailed calculation is given for the example of a typical polyclinic building. The results of the calculation are compared with the standardized energy characteristics of this type of buildings.
The paper presents the results of measuring the distribution of the droplet diameters in the nebulization generated by the nozzle at the values of the pressure of the supplied water of interest based on the interference method for recording the Ml-scattering of laser radiation on droplets. Studies were carried out on the nozzle with cold filtered tap water supply under pressure. In total, three experiments were carried out with a pressure of 10, 14 and 18 bar.The nozzle was located in a closed container with transparent walls measuring 40x60x120 cm3 (capacity - rectangular parallelepiped) approximately in the center of the inner volume of the container. The need to locate the object of research in a closed container is due to the sensitivity of electronic equipment to moisture. Outside the container there were optical devices: laser optics forming optics and a video camera with a macro lens. The maximum speed (modulo) is practically independent of the pressure and is 8.5 m/s at a distance of 15 cm from the nozzle outlet. This can be explained by the fact that the drop undergoes strong resistance to movement from the air side in the tank. The Stokes resistance force, proportional to the speed, quickly brakes the drop, so that by the time the droplet arrives in the imaging area, its speed decreases dramatically. With an increase in pressure from 10 to 18 bar, the average diameter of the spray nozzles of the nozzle increases from 17.3 to 20 μm.
Energy consumption by building environment systems is based on calculation of annual expenses of thermal and electric energies on microclimate provision in premises of the building at its heating and cooling. Numerical values of energy characteristics and indicators are regulated by normative documents depending on the purpose of a particular building. To determine the annual energy consumption of the building, it is necessary to know the thermal and geometric characteristics of its individual enclosing structures, as well as the conditions of the building, depending on the climatic conditions of the region in which it is located. The analysis of the existing normative documents on calculation of annual expenses of thermal and electric energy consumed by building environment systems in premises of public purpose buildings was carried out. This made it possible to perform the necessary calculations to determine the energy consumption for the heating and cooling periods. The results were compared with the normative values.
The saving of resources, energy and the use of natural refrigerants in refrigeration systems is one of the basic vectors of the innovative development of our country. One of the promising ways to solve these problems is the use of vacuum-evaporation ice generator with using an ice slurry storage system, together with energy-saving technologies using renewable energy sources. The article describes the principle of ice production in the vacuum-evaporation ice generator. The advantages and disadvantages of the methods of obtaining ice in vapor-compression refrigeration systems and vacuum evaporative plants are considered. A comparison is made between the consumption of electricity by vapor-compression refrigeration and vacuum ice makers in the production of ice, and heat pumps using air and seawater as a source of heat. Energy-efficient plants using vacuum-evaporative ice generators in cold storage systems are considered; in combined cooling and heating systems; with a heat pump.