Thesis (M.E.F.E.)--University of Canterbury, 2007. / Typescript (photocopy). "Fire engineering research report." "March 2007." Includes bibliographical references (p. 203-208). Also available via the World Wide Web.

Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 2004. / Field problem. Includes bibliographical references.

University of Macau / Faculty of Science and Technology / Department of Electromechanical Engineering

Thesis (Ph. D.)--Worcester Polytechnic Institute. / Keywords: program; testing; modeling; blow down; discharge; dry chemical. Includes bibliographical references (p. 364-375).

Thesis (M. App. Sc.)--Carleton University, 2005. / Includes bibliographical references (p. 322-325). Also available in electronic format on the Internet.

Thesis (Ph. D.)--Worcester Polytechnic Institute. / Keywords: suppression; drop size; high flash point pool fire. Includes bibliographical references (p. 210-218).

This thesis demonstrates how the response of fire detection and automatic sprinkler systems can be designed or analyzed. The intended audience is engineers involved in the design and analysis of fire detection and suppression systems. The material presented may also be of interest to engineers and researchers involved in related fields. National Bureau of Standards furniture calorimeter test data is compared to heat release rates predicted by a power-law fire growth model. A model for calculating fire gas temperatures and velocities along a ceiling, resulting from power-law fires is reviewed. Numerical and analytical solutions to the model are outlined and discussed. Computer programs are included to design and analyze the response of detectors and sprinklers. A program is also included to generate tables which can be used for design and analysis, in lieu of a computer. Examples show how fire protection engineers can use the techniques presented. The examples show how systems can be designed to meet specific goals. They also show how to analyze a system to determine if its response meets established goals. The examples demonstrate how detector response is sensitive to the detector's environment and physical characteristics.

"The primary purpose of this research was to quantify fire suppression and fire intensification phenomena for water spray application to high flash point hydrocarbon oil pool fires. Test data and analyses of the phenomena include the drop size distribution and application and delivered densities of various water sprays, and spray-induced oil cooling and oil splattering for mineral seal oil and for cooking oil 30-cm diameter pool fires. Four different types of tests were conducted as described below. A Dantec Particle Dynamic, phase Doppler, Analyzer was used to measure the water drop sizes and velocities generated by 13 selected nozzles and sprinkler heads. Most measurements were made 0.91 m (3 ft) below the nozzles/sprinklers, since this was the location of the center of the hydrocarbon pool in later fire tests. The correlations for the volume-median drop diameter, dw, were of the form , where D is the nozzle orifice and is the spray Weber number based on D and the nozzle velocity. A ring burner was designed and constructed for uniformly heating oil pool surfaces from above and igniting them. The resulting oil temperatures while the oil was heated to its flash point satisfied the one-dimensional transient heat conduction model for a semi-infinitely thick solid with a shallow heated layer near the surface. Water sprays actuated when the oil surface temperature reached its flash point rapidly cooled the heated layer and caused mixing with the cooler oil below. Fire suppression tests were conducted to determine the relationship between required water spray density, drop size, and oil temperature in order to achieve suppression. A data correlation using non-dimensional parameters was developed to quantify the fire suppression criteria for the high flash point oil fires. Oil pool fires with the higher flash point oils, such as the 291oC flash point soybean oil, could be suppressed with much lower water densities than those of the lower flash point (137oC) mineral seal oil. However, if the water spray drop sizes are sufficiently small, the lower flash point oil fires can also be extinguished with lower spray densities. The NFPA 15 specified critical water density (0.30 gpm/ft2, 12 mm/min) to extinguish high flash point pool fires is only valid for mineral seal oil when the drop size is lower than about 300 µm. It is valid with larger drop sprays only when the flash point of the oil is higher than 190 according to the correlation developed here. Spray-induced pool fire intensification tests were conducted under a fire products calorimeter for measuring heat release rates. Supplemental oil vaporization rate tests were also conducted to determine the contributions of oil vaporization and oil splattering to the intensified fire. Results showed that vaporization could only account for between 1% and 1.7% of the heat release rate in intensified mineral seal oil fires, and less than 1% of the heat release rate in intensified soybean oil fires. The remainder is due to spray-induced oil splattering, which increased with increasing drop Weber number as well as increased oil temperature. The heat release rate is enhanced by factor from 2.12 to 5.55 compared to the heat release rate of free burning cooking oil. For mineral seal oil, this ratio is in the range 0.92 to 1.25 for the spray conditions tested. Correlations with the dimensionless factors of and the Weber number of the water spray were also developed to quantify the ratio of the splattered oil to applied spray density."

An engineering method has been developed for calculating the blowdown of agent from a pressurized dry chemical fire suppression system supply cylinder, and the flow rate of agent through a piping delivery system. Its goal is to provide the means to determine the blowdown time and agent delivery capabilities of pre-engineered and simple engineered systems. The method is based on the treatment of the two-phase powder-gas flow as an equivalent fluid with thermodynamic properties that account for agent composition and the relative proportions of agent and gas propellant. The mixture is treated as compressible, and the expansion in the supply tank is assumed isentropic. A key assumption in the model is that the agent (powder) mass fraction remains constant, in both the tank and delivery system. Laboratory tests were conducted to examine the validity of the model and its assumptions. Simple systems were discharged to measure pressures in the cylinder and nozzle inlet during discharge, and the mass of agent discharged. A 0.43 cubic foot cylinder containing 0-25 lbm of either sodium bicarbonate or moammonium phosphate, pressurized at up to 300 psig of nitrogen, was discharged, either alone, or with an 8-foot length of piping and a single nozzle. For the cylinder by itself, gas alone pressurized to 300 psig discharged in 1.5 seconds, while 25 lbm of sodium bicarbonate agent pressurized to 300 psig discharged in 5.2 seconds with 0.10 lbm of agent remaining in the cylinder after discharge. There was no significant difference in the discharge times or residual masses in the cylinder after discharge between the sodium bicarbonate and monoammonium phosphate agents. For a cylinder-pipe-nozzle system, gas-alone discharges pressurized to 300 psig took 7 seconds, while 25 lbm of sodium bicarbonate agent pressurized to 300 psig discharged in 26 seconds with 0.64 lbm of residual agent in the cylinder after discharge. Predictions generated by the model were compared with test results. Cylinder alone gas-only discharge model predictions agreed well with test data for the full duration of tests using a discharge coefficient of 0.380 to characterize the gas flow through the dip tube / valve assembly; a simple isentropic analytical model gave a good prediction using a discharge coefficient of 0.430. Gas-solids predictions using a discharge coefficient of 0.500 agreed well with test data up to the observed inflection point near the end of discharge. This inflection point is caused by the agent in the cylinder reaching the bottom of the dip tube, resulting in reduced flow of agent from the cylinder, and thus reducing the mass fraction of the flow. Cylinder-pipe-nozzle model discharge predictions for gas-only discharges agreed well with test data for the full duration of tests using a discharge coefficient of 0.470 for the 0.173-inch diameter nozzle used in the testing. Model predictions agreed well with the gas-solids mixture test data up to the inflection point, using a discharge coefficient of 0.999. The constant mass fraction assumption results in residual agent mass predictions of 2.0 lbm or more after discharge. Test data shows 0.6 lbm or less of residual. This residual discrepancy, and the presence of the inflection point observed in solids-gas tests, suggests that the constant mass fraction assumption is not adequate to accurately model agent discharge from the cylinder. Using an appropriate discharge coefficient, the model can be used to determine approximate discharge times for simple systems.

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