scholarly journals THE INFLUENCE OF ENCLOSURE ON BURNING CHARACTERISTICS OF OSB FURNISHINGS

Wood Research ◽  
2021 ◽  
Vol 66 (6) ◽  
pp. 969-980
Author(s):  
VLADIMÍR MÓZER ◽  
PETR HEJTMÁNEK ◽  
DANIELA PITELKOVÁ ◽  
LUCIE HASALOVÁ
Keyword(s):  
Fire Hazard ◽  
Full Scale ◽  
Total Heat ◽  
Ignition Source ◽  
Thermal Feedback ◽  
Fire Modelling ◽  
Gas Burner ◽  
Full Scale Tests ◽  
Office Furniture

This paper presents a series of full-scale tests conducted with office furniture made from OSB boards. Ignition source (30 kW gas burner) position and enclosure effects, free burn vs. ISO 9705 room, were evaluated from the perspective of instantaneous (HRR) and total heat (THR) released by the fuel packages. It was found that both of the evaluated factors have impact primarily on HRR – the peak ranging from 874 kW to 1 154 kW was delayed by approx. 50 to 60 s in the free-burn experiments; the THR remained relatively consistent at approx. 875 ± 30 MJ, meaning that in the observed period very similar amounts of fuel were burned. The thermal feedback within the enclosure seemed to be partially counteracted by the lack of oxygen, resulting in slightly higher HRR in free-burn test following the first peak. The findings of the research are applicable to fire hazard prediction by fire modelling.

Investigation of planing craft maneuverability using full-scale tests

2021 ◽  
pp. 147509022110303
Author(s):  
Kazem Sadati ◽  
Hamid Zeraatgar ◽  
Aliasghar Moghaddas
Keyword(s):  
Full Scale ◽  
Performance Characteristics ◽  
Forward Speed ◽  
Speed Reduction ◽  
Planing Craft ◽  
Full Scale Tests ◽  
Turning Maneuver

Maneuverability of planing craft is a complicated hydrodynamic subject that needs more studies to comprehend its characteristics. Planing craft drivers follow a common practice for maneuver of the craft that is fundamentally different from ship’s standards. In situ full-scale tests are normally necessary to understand the maneuverability characteristics of planing craft. In this paper, a study has been conducted to illustrate maneuverability characteristics of planing craft by full-scale tests. Accelerating and turning maneuver tests are conducted on two cases at different forward speeds and rudder angles. In each test, dynamic trim, trajectory, speed, roll of the craft are recorded. The tests are performed in planing mode, semi-planing mode, and transition between planing mode to semi-planing mode to study the effects of the craft forward speed and consequently running attitude on the maneuverability. Analysis of the data reveals that the Steady Turning Diameter (STD) of the planing craft may be as large as 40 L, while it rarely goes beyond 5 L for ships. Results also show that a turning maneuver starting at planing mode might end in semi-planing mode. This transition can remarkably improve the performance characteristics of the planing craft’s maneuverability. Therefore, an alternative practice is proposed instead of the classic turning maneuver. In this practice, the craft traveling in the planing mode is transitioned to the semi-planing mode by forward speed reduction first, and then the turning maneuver is executed.

Full-scale tests of the trash racks of the Kapchagai hydroelectric station

1984 ◽  
Vol 18 (4) ◽  
pp. 166-170
Author(s):  
A. L. Rakhmanova ◽  
I. O. Rybak
Keyword(s):  
Hydroelectric Station ◽  
Full Scale ◽  
Full Scale Tests

THE RULE OF COMBINING A PRIORI AND EXPERIMENTAL INFORMATION IN THE TASKS OF MANAGING TESTS OF COMPLEX TECHNICAL PRODUCTS ACCORDING TO THE BERNOULLI SCHEME

2020 ◽  
pp. 3-13
Author(s):  
Yu. I. Buryak ◽  
A. A. Skrynnikov
Keyword(s):  
Field Experiments ◽  
A Priori ◽  
Field Tests ◽  
Experimental Information ◽  
Full Scale ◽  
Testing Complex ◽  
Series Of Experiments ◽  
Full Scale Tests ◽  
Technical Products

The article is devoted to the substantiation of the procedure for testing complex technical systems to assess the probability of performing the task, taking into account a priori data obtained from the results of modeling, field tests of components and prototypes, operation of analogues, etc. The conditions for the formation of a combined sample consisting of field experiments and experiments counted on the results of modeling are justified. Data uniformity is checked using the Student's criterion. The minimum volume of full-scale tests is determined by the requirement of equality of the amount of Fischer information about the estimated parameter obtained during full-scale tests and at the expense of a priori data A strategy for conducting field experiments is proposed, in which the required quality of evaluating the probability of completing the task is achieved with the minimum possible number of field experiments. At the first stage, a series of experiments with a volume equal to half of the required sample size is performed. At the second stage, the experiments are conducted sequentially with an assessment after each experiment of the requirements for the amount of information about the evaluated parameter and for the uniformity of data. Experiments are terminated when the specified requirements are met, and then a combined sample is formed, which is used to evaluate the probability of the system performing the task. A model example is considered. The estimation of the gain in the number of experiments performed at different probability values was carried out.

Destress blasting in deep mines of NorNickel’s Polar Division

2021 ◽  
pp. 32-36
Author(s):  
G. V. Sabyanin ◽  
S. Yu. Shilenko ◽  
A. V. Trofimov ◽  
A. P. Kirkin
Keyword(s):  
Horizontal Plane ◽  
Large Diameter ◽  
Geophysical Methods ◽  
Full Scale ◽  
Underground Mines ◽  
Destress Blasting ◽  
Drilling Cost ◽  
Full Scale Tests ◽  
Polar Division ◽  
Oktyabrsky Mine

Talnakh and Oktyabrsky ore fields are estimated as rockburst-hazardous starting from the depth of 700 m downward according to safety rules. This means that mining is only permitted within certain protected zones. At the present times, such protected zones are generated in underground mines by means of the large-diameter destressing drilling. Despite proved efficiency, the high cost and large amount of the destressing drilling are the grave faults of this approach. Aiming to save drilling cost, it is proposed to make rock mass rockburst-unhazardous using destress blasting. This article gives a brief description of the destress blasting mechanism. This method has been effectively used in relaxation of pillars from stresses before extraction of the reserves from the pillars both in Russia and abroad. In Oktyabrsky Mine stress relaxation of pillars was implemented by slotting, and the drilling and blasting data were available. This study proposes to destress rock masses by means of directional destress fracturing in horizontal plane through blasting of decked charges of special design. The initial parameters for destress blasting using holes with diameters of 76 and 130 mm are determined. The charge design aimed to ensure a zone of fractures in the horizontal plane, at minimized vertical fracturing is described. This information can be used in planning of full-scale tests to refine parameters and application ranges of the method. For the full-scale tests, it is suggested to undertake destress blasting at different blast patterns on different test sites, and to compare the results with the current destressing method (destressing drilling). Efficiency can be proved using geomechanical and geophysical methods. The authors appreciate participation of V. P. Marysyuk and T. P. Darbinyan from NorNickel’s Polar Division in this study.

Sign in / Sign up

Export Citation Format

Share Document