Experimental studies of the influence of mobile fan positioning parameters on the ability to transport the air stream into the door opening

Abstract

The article aims to determine the influence of fan positioning parameters, i.e., its distance from a door opening (1–7 m) and the angle of inclination of the impeller axis in relation to the ground (0°–18°) on the amount of air flow pumped through a door opening. The experiment was carried out using a mock-up simulating a door opening, on which a measurement plane was located, without the cubic capacity (building structure) behind the door opening. The volumetric air flow stream was determined based on measuring (at 50 measuring points) the velocity of the air stream blown onto the surface of the door opening mock-up. Four commercial positive pressure ventilators, commonly used in rescue operations, with a power of 0.6–6.3 kW were tested. The tests showed that the value of the air flow stream at the most favourable setting (distance in the range of 3–5 m and the angle of the impeller axis to the ground in the range of 5°–12.2°) is included in the range of 18,304 ± 2460 m3/h to about 45,189 ± 4619 m3/h. Such settings cause the air stream to be aimed at the central area of the door opening. Imprecise mobile fan arrangement may reduce the flow rate from 41 to 76% in relation to the most favourable results.

Problems of operation of positive pressure ventilators on the basis of surveys of Polish officers of the State Fire Service

“…Additional expectations and desired improvements reported by respondents include, for example, increasing the range of possibilities for setting the angle of the ventilator impeller (also introducing control of the direction of the airstream below the horizontal axis). Currently, in the commonly used units, the value for changing the position of the ventilator impeller from the horizontal is between 0° and 18° (upward airflow direction), with the most common four recommended positions 88 . The remaining open-ended responses related to drive units, reducing CO emissions from internal combustion engines and reducing the cost of purchasing electric-powered ventilators with increased uptake.…”

Research on the Distribution of Axial Excitation of Positive Pressure Ventilators in the Aspect of Stability Safety of the Load-Bearing Frame

“…1), the technical parameters of which are included in Table 1. According to research by Warguła and Kaczmarzyk from 2022, the tested fans belong to the most popular group used in the State Fire Service in Poland [9,34]. The adopted test procedure involved performing the test with two speeds of the ventilator impeller.…”

“…Furthermore, identifying the main sources of vibration and determining the direction of loss of stability of the ventilator frame and the consequent change in its position relative to the opening into which it pumps air. Imprecise mobile fan arrangement may reduce the flow rate from 41 to 76% in relation to the most favorable results [34]. Research was conducted for the four most popular ventilators used by the State Fire Service (representing the main group of used equipment).…”

Positive pressure ventilator of a conventional type working in sets – analysis of the effectiveness of positioning methods

“…Focusing on the issue of positioning the mobile ventilator, it should be emphasized that the positive pressure ventilator should be positioned in such a manner in which it works most efficiently, which is measured by assessing the volume flow rate injected into the building volume. This feature should be verified based on appropriate research methodology [3][4]19 . This methodology should allow verification of its performance in their final conditions of use [5][6][7][8] .…”

“…Achieved air flow rates for the tested configurations(1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11), where AVGarithmetic mean of the flow rate (m 3 /h) and confidence interval (p=0.05).…”