Reducing energy capacity and increasing the environmental safety of industrial areas when using radiative heating systems based on water infrared radiators

Introduction. It has been repeatedly proven that the use of radiant heating systems leads to an increase in the environmental safety of industrial premises by increasing their energy efficiency. The most promising solution is the use of gas infrared emitters, in which there is no intermediate coolant, and the heat of combustion of the gas enters the room. However, such a solution has a number of limitations on gas availability, comfort and fire hazard. Also, a highly efficient solution is the use of water infrared emitters, which can be represented by emitting panels or emitting profiles that use an intermediate coolant, but do not have many limitations inherent in gas systems. Materials and methods. This study was conducted in the Laboratory of radiant Heating of NNGASU and is devoted to the study of the peculiarities of the formation of the temperature regime in rooms heated by water infrared radiators, as well as the thermal regime of external enclosing structures in these rooms. Results. Based on the results of the experiments, the authors concluded about the formed thermal regime in rooms with heating systems based on water infrared emitters. It is proved that the use of radiant heating leads to a more uniform temperature regime in a heated room, and less overheating of the room covering than when using convective heating systems. Conclusions. The energy efficiency of the use of radiant heating systems based on water infrared emitters has been proven. The study showed that the system of water radiant heating allows to reduce the gradient of air temperature in height not only in large-volume rooms, such as workshops, depots, gyms, but also in rooms with a low height of the coating location. This feature allows you to reduce heat losses through the coating. The temperature regime in the working area of the room with the use of radiant water heating, in comparison with convective, remains unchanged.

Effect of boron on HEM radiant ignition characteristics

The paper presents the ignition characteristics of high-energy materials (HEMs) containing ammonium perchlorate, butadiene rubber, and a mixture of Al/B nanopowders with different component ratios. Bimetallic systems based on aluminum with boron increase the reactivity and intensify the ignition of boron particles, which helps to decrease the critical ignition conditions of HEMs during heating. It is shown that the use of systems based on aluminum-boron reduces the delay time (by 17–52 %) and the ignition temperature of propellants in comparison with a HEM containing aluminum powder, and increases the activation energy of HEM during radiant heating.

Thermal regime of the local working zone in the industrial premises under radiant heating conditions

The results of experimental studies on recording temperatures and heat fluxes for the local working zone in industrial premises under radiant heating conditions and supply and exhaust ventilation operation are presented. The characteristics are measured on the surface of the horizontal remote panel directly under the radiator and along the wall with the ventilation inlet. Experimental results show that mixed convection caused by the operation of air exchange systems leads to mixing of air masses and more intensive cooling of the horizontal panel surface, as well as air, compared to the natural convection regime.

Analysis of Deformation and Stresses of a Lightweight Floor System (LFS) under Thermal Action

The lightweight floor system (LFS) with a heating coil is one of many types of radiant heating systems. It differs from most of the others, as it has a much higher thermal efficiency at low flow temperature. To verify whether adhesive mortars can safely connect the ceramic floor with the insulating substrate, the deformations and stresses values of all light system layers under thermal action should be checked and compared to their maximum strengths. For this purpose, an LFS test field was conducted using the strain gauges and digital measurement techniques, and floor displacements and deformations were determined. The results obtained from the tests were confirmed by finite element method calculations. It was also found that the stress of each floor component was much lower than their strength. This proves that the LFS with a heating coil, without metal lamellas, meets the safety regulation for use. The results of the analysis can be useful in the design of heated/cooled LFSs.