METHOD OF ACTIVE INFLUENCE ON REDUCING FLAME AND SURFACE TEMPERATURE BY MEANS OF WATER JET OF FAN TYPE

  • Yu. Yu. Dendarenko 1Cherkasy Institute of Fire Safety named after Chornobyl Heroes of National University of Civil Defence of Ukraine
  • Ye. O. Tyshchenko Educational methodical centre of civil protection and life safety of Cherkasy region, Cherkasy
  • Yu. M. Senchyhin National University of Civil Defence of Ukraine
  • V. I. Dyven Cherkasy Institute of Fire Safety named after Chornobyl Heroes of National University of Civil Defence of Ukraine
  • O. D. Blashchuk Cherkasy Institute of Fire Safety named after Chornobyl Heroes of National University of Civil Defence of Ukraine
Keywords: heat current, water spray, nozzle, Liquefied Petroleum Gas

Abstract

The possibility of using sprayed water jets is established, primarily radial air jets, in vertical and horizontal planes in order to reduce the temperature of the burning Liquefied Petroleum Gas, starting from the cut-off of its expiration into free space. Various technical means of supplying water in a spray and spray nozzles for their creation, which are used in solving the problem of reducing the temperature of the burning Liquefied Petroleum Gas are viewed. It has been established that the active phase of the sprayed water jet is most effective (0,5-0,75 of the lengths), which, acting under the cut of the flame is crushed to a finely dispersed phase under the influence of a high-speed gas jet. As can be seen from the above, the heating rate of the finely dispersed water phase is increased up to the gaseous state, which leads to a decrease of the temperature of the flame in its middle combustion zone. Consequently, in the flame temperature will be much lower than the temperature of the flame cone, and, as a result, close to the extinction temperature. The authors recommend the use of modern jet-forming devices to realize this goal – nozzles NRT-5, NRT-10, NRT-20, NRS, as well as hand nozzles of the kind RSK-50, RS-А, RS-B, PROTEK. In order to cool, for example, one horizontal ground steel tank on both sides, it is necessary to use at least two hydraulic guns, which will act as maneuvering. In this case, the flow of water from the hydraulic gun with a diameter of the nozzle 25 mm will be from 16 to 18 liters per second. Therefore, the task is to find, calculate and experimentally prove the efficiency of the thermal screen, which is created in the form of a moving water surface that can effectively protect a particular physical object from the thermal impact of the heat zone. In order to reduce the flow of water to cool the tanks, the authors suggest using the NRS to create radial (flat) water jets. Application of such a nozzle allows to increase the area of simultaneous cooling of the maximum surface area per unit time due to the expansion of the angle of the spray jet spark. The water consumption does not exceed 13 liters per second.

Published
2020-11-30