Experimental Study on Propane Jet Fire Hazards: Thermal Radiation

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Experimental study on propane jet fire hazards: Thermal Radiation Bin Zhang, Yi Liu, Delphine M Laboureur, and M. Sam Mannan Ind. Eng. Chem. Res., Just Accepted Manuscript • DOI: 10.1021/acs.iecr.5b02064 • Publication Date (Web): 08 Sep 2015 Downloaded from http://pubs.acs.org on September 8, 2015

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Industrial & Engineering Chemistry Research

Experimental study on propane jet fire hazards: Thermal Radiation

Bin Zhang, Yi Liu, Delphine M. Laboureur and M. Sam Mannan* Mary Kay O’Connor Process Safety Center Artie McFerrin Department of Chemical Engineering Texas A&M University System College Station, Texas 77843-3122, USA (979) 862-3985, [email protected]

Abstract

Jet fires are one of the major hazards in the oil and gas industry, and half of the reported jet fires caused a domino effect that enlarged the incident. Previous work with propane focused on vertical jet fires. In this work, both horizontal and vertical fires were studied through 21 tests conducted at the Brayton Fire Training Field. The fires were sustained by either vapor or liquid propane. The visualization of flames using both video and infrared cameras identified that cylindrical shape was a good description of vertical and horizontal jet fires. For the vertical fires, a correlation was developed for radiation against distance from the flame axis. For horizontal fires, the solid flame model was used to predict radiation; the selected parameters were evaluated by statistical performance measures. The effects of vapor flow rate, surface emissive power, and the fraction of radiation were also studied. Keywords: Propane; jet fire; radiation intensity; surface emissive power; solid flame model

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Table of Contents (TOC) Graphic


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Nomenclature AFC E F H H I Q R T X Ε Η Σ Τ

flame cylindrical surface area (m2) surface emissive power (kW m-2) view factor relative humidity combustion heat (kJ kg-1) thermal radiation intensity (kW m-2) propane vapor flow rate (kg s-1) total heat of combustion (kW) radiative heat (kW) flame temperature (K) radial distance from flame surface (m) flame emissivity fraction of heat radiation Stefan–Boltzmann constant (W m-2 K-4) atmospheric transmissivity



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1 Introduction Jet fires are a major hazard in the onshore and offshore process industry, which was best demonstrated in the Piper Alpha accident. The jet fire from broken riser caused multiple violent explosions and major structural collapses1. Since jet fires occur with high pressure leaks, they instantaneously reach full intensity and leave little time to prevent flames. The flame impingement is the direct hazardous effect; however, the thermal radiation will affect a larger area on personnel and thermally sensitive equipment. The thermal effects may melt the equipment and cause mechanical failures, or heat the liquid in vessels and cause an overpressure. Fatalities were caused in 44% of accidents involving jet fire, mainly because jet fires often lead to a more severe event, e.g. explosion, which is called the domino effect2. Jet fires have been studied using many different fuels, including hydrogen, natural gas, hydrogen/natural gas mixture and propane3–7. It has been reported that 61% of jet fire involved LPG 2, which primarily consists of propane. Therefore, propane was used in many experimental works involving jet fires in the past6–9. Among the reported works, the majority studied vertical fires, while horizontal fires were seldom investigated. The solid flame model is widely used to predict the thermal radiation of a fire, since it has a good agreement with experimental results in both far and near field. The point source model is simple, but is accurate only in the far field10. According to the solid flame model, the thermal radiation is obtained by the product of view factor (F), surface emissive power (E), and atmospheric transmissivity (τ) as illustrated in Eq. (1). The fire is usually treated as a non-blackbody as shown in Eq. (2), and a formula developed for flares as shown in Eq. (3) was found suitable to calculate the atmospheric transmissivity for jet fires6,11. View factor is also known as configuration factor. In radiative heat transfer, a view factor, F(A→B), is the proporJon of the radiaJon which leaves surface A that strikes surface B12.


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=

(1)

=

(2) ⁄

100 ⁄ 30.5 (3) = 0.79 ℎ This work conducted jet fire tests with propane ejected both vertically and horizontally. The thermal radiations were studied through measurements at various locations in each test. In combination with the geometry information of the flame obtained from the cameras, the surface emissive power and radiation fraction were investigated. The performance of the solid flame model was evaluated with selected parameters.

2 Experiment and Methodology 2.1 Experimental setup The tests were conducted at the Brayton Fire Training Field in College Station, TX, USA. As shown in Figure 1, one horizontal nozzle and one vertical nozzle were used to eject either vapor propane or liquid propane (two phase, since liquid propane may vaporize in the pipe before it was released by nozzles). The inside diameter of the vertical nozzle was 2.54 cm and the inside diameter of the horizontal nozzle was 1.91 cm. The red dots in Figure 1 are the release points. The horizontal nozzle has 10 degree angle with x axis towards y axis (the angle between x axis and north direction is 50 degree, and the angle between horizontal nozzle and north direction is 60 degree). The thermal radiation was measured by 11 radiometers of three ranges (Medtherm Corporation, USA), 30 kW/m2 (Schmidt-Boelter type), and 120 kW/m2and 300 kW/m2 (Gardon gage type).

The

radiometers were installed at 0.85m above the ground. One CCD camera and one infrared camera (FLIR SC660) were used to capture the flame. A weather station (Davis Vantage Pro2) was used to monitor weather conditions, which are given in Table 1.



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Figure 1 Experimental Setup for the field tests Table 1 Weather conditions Air temperature [°C] Relative humidity Wind speed [m/s] Wind direction Rain [mm]

25.3 ± 1.7 50.9 ± 9.3 2.2 ± 0.7 NNE and N and NNW

0

2.2 Summary of tests Four series of tests were conducted as summarized in Table 2, which consisted of 21 tests altogether. Commercial grade of propane was used in the tests, which consists of more than 90% of propane. The radiometers were arranged differently for each series of tests, since two nozzles were switched back and forth during the experiment, and radiometers were relocated to measure the radiation. The release pressure was up to 7.5 atm for the horizontal release. The flow rates were measured only when vapor propane was used for the horizontal tests. This information was not measured for vertical tests, since propane was released using a different piping system, which was not instrumented for measurement.


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Table 2 Summary of field tests Nozzle diameter [cm] 1.91 1.91 1.91 1.91 1.91 1.91 1.91 1.91 1.91 1.91 2.54 2.54 2.54 1.91 1.91 1.91 1.91 1.91

Nozzle direction Horizontal Horizontal Horizontal Horizontal Horizontal Horizontal Horizontal Horizontal Horizontal Horizontal Vertical Vertical Vertical Horizontal Horizontal Horizontal Horizontal Horizontal

Flow rate* [kg/h] 1 liquid 2 vapor 3 vapor 335 4 vapor 331 5 vapor 334 Series 1 6 vapor 363 7 vapor 393 8 liquid 9 liquid 10 liquid 11 liquid Series 2 12 liquid 13 liquid 14 liquid 15 vapor 99 16 vapor 169 17 Vapor 151 18 Vapor 53 Series 3 397 241 195 19 Vapor 1.91 Horizontal 143 90 59 20 Vapor 1.91 Horizontal Series 4 21 Liquid 2.54 Vertical *Test 19 has six different flowrates and each flowrate lasted about 50s Test #

Fuel type

3 Results and Discussions 3.1 Flame visualization Two visualization techniques were used to study the fires, one with the CCD camera and one with the infrared camera. The CCD camera allows the study of the geometry of a visible flame.

The geometry information includes shape, length, and width.

A

comparison of the various shapes, such as ellipse, frustum of a cone, inverted cone, and cylinder, was conducted by Palacios13. This comparison concluded that cylinder could represent the propane vertical fire in still air. In this work, the camera images in Figure 7 ACS Paragon Plus Environment


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2 indicate a cylindrical shape for both horizontal (Test 20) and vertical (Test 21) fires. Other tests show a similar flame shape. However, additional study was conducted for horizontal flames to compare four shapes - rectangle (cylinder), ellipse, kite, and frustum of a cone14. The kite and rectangle (cylinder) were found to be equally good at representing the horizontal flames. Besides the shape, length and width are also important to determine the reach of the flame and thermal radiation to a given target. In this work, the liftoff was defined as the distance from release point to the closest point of the flame boundary. The flame length was defined as the distance from release point to the furthest point of the flame boundary, which includes the liftoff. The flame length in the work ranges from 1m to 13 m. The infrared camera also provided the flame geometry information, but the decision on temperature contour must be made by analyzing the image for flame boundary. Although Palacios found that an 800 K contour is suitable to be treated as the flame boundary due to a good agreement on occupied area for visible and infrared images13, the video analysis for this work found a lower temperature (600 K or 700 K) contour had a better agreement with visible images in terms of the flame length14. Therefore, the geometry information used in this paper was obtained from the CCD camera to avoid confusion.

Figure 2 flame visualization using CCD camera and infrared camera (temperature bar unit: K)


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3.2 Vertical fires Four vertical fires were conducted with liquid propane. The liquid fuel tends to produce a larger flame7. The largest flame was more than 13.2 m in Test 21, and was too large to be captured by the camera. The smallest flame was about 8.5 m in Test 11. The radiation decay with distance is shown in Figure 3. The radiation decay had a similar trend for different size fires. A power correlation was proposed to fit the radiation data, since it is consistent with the prediction using a solid flame model in combination with a cylinder approach for view factor. The correlation is given in Table 3, which summarizes the coefficients and R2 for each test.

Figure 3 Radiation intensity at various distances for vertical fires Table 3 Correlations of radiation with distance Test # 11 12 13 21

y=axb y = 3877x-2.96 y = 4669x-3.0 y = 2043x-2.6 y = 1183x-2.3

R2 0.81 0.81 0.87 0.91

3.3 Horizontal fires 3.3.1 Effect of flow rate The impact of flow rate on the flame geometry is shown in Figure 4. The flow rate of vapor propane did not affect the average width of the flame in the range of this study. The impact of the flow rate on two kinds of flame length was studied. One is the flame length including liftoff as defined previously in this paper, and the other is the flame length excluding liftoff. The flame length increased with flow rate, but the flame length 9 ACS Paragon Plus Environment


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increased slowly at approximately 0.04 kg/s or higher flow rates. The liftoff also increased with flow rate and maintained a high increasing rate through the range. Therefore, the flame length excluding liftoff increased with flow rate at the low range, but remained relatively stable at the high range. The area (rectangle flame shape) of flames had a similar trend with the flame length excluding lift, because the area was obtained for the visible flame and primarily depended on the length excluding liftoff, which is the visible flame length.

Figure 4 Flame geometries at different propane gas flow rates The propane flow rate was gradually reduced in Test 19 as shown in Figure 5. The thermal radiation decreased with the flow rate as shown for two selected radiometers. However, the influence of flow rate on radiation varied with the locations of the measurement. For instance, the flow rate had a larger impact on R5 than R1 in test 19. At the highest flow rate, R5 was 1.9 times of R1; at the lowest flow rate, R5 was 1.4 times of R1. The positions of R1 and R5 can be found in Table 4.


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Figure 5 Thermal radiation at various propane flow rates in Test 19 (a Series 3 test) The thermal radiation of Series 3 tests is shown in the Figure 6. Similarly, the radiation increased with flow rate for all the radiometers. The position of each radiometer differentiated the impact of flow rate on the radiation. For vertical fires, the distance is the only factor to affect the radiation at a given flow rate as shown in Figure 3 and other works7. However, the relative position of radiometer along the flame axis is also an important factor for horizontal fires. The coordinate of each radiometer in Series 3 tests is summarized in Table 4 with the coordinate origin shown in Figure 1. R5 and R6 were placed at a similar distance (y value) from the flame, but R5 had a much larger radiation than R6 at a given flow rate, because R5 was closer to the center of the flame along the flame axis (high x value). Therefore, a simple plot of radiation against distance is not enough to explain the experimental results. This idea can be explained in Figure 7. For a given flame length, all radiometers had the same height (x value) in vertical fire tests as illustrated for locations A and B, so the distance from the flame (y value) is the only parameter to determine the view factor, therefore, the radiation. In the horizontal fires, both distance from the flame (y value) and relative position along the flame (x value) can be different, such as A and C. These two parameters can both affect the view factor and radiation. Therefore, a solid flame model is required for the radiation prediction of horizontal fires, since its view factor considers the flame size and position of interest. The radiation was less affected by the flow rate in a position that was far from the flame axis and the flame center, such as R10. 11 ACS Paragon Plus Environment


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Figure 6 Thermal radiation and propane gas flow rate in Series 3 tests Table 4 Radiometer position in Series 3 tests Series 3 Radiometer # R1 R2 R5 R6 R9 R10 R11

Horizontal fire x y 4.9 4.1 1.9 5.4 3.6 3.1 0.9 3.2 4.8 2.7 1.5 6.9 3.6 5.2

Unit: m z 0.85 0.85 0.85 0.85 0.85 0.85 0.85

Figure 7 Radiation measurement difference for vertical and horizontal flames


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3.3.2 Solid flame model The use of solid flame model involves the calculation of view factor (F), surface emissive power (E) and atmospheric transmissivity (τ). View factor calculations can be very complicated if the flame shape is not properly chosen. Since both cylinder and kite were found to represent the flame well, cylinder was chosen due to its simplicity. A formula for an element to the exterior of a right circular cylinder of finite length was used for view factor calculation15. Surface emissive power can be obtained using Eq. (2). One zone model, which uses a uniform temperature for the whole flame, was commonly used in previous work7,9,16. Palacios compared the one zone model to the three zone model, which divided the flame into three zones with different temperature for each zone; however, no significant improvement was found for the three zone model6. Therefore, one zone model was used in this work. Flame temperature T=1300 K and emissivity ε=0.45 were used, since similar values were reported6, and they offered good predictions for thermal radiation as shown in Figure 8. Two methods were used for atmospheric transmissivity. One treated τ as 1, and other used Eq. (3). The selected parameters were evaluated by statistical performance measures as shown in Table 5. These statistical performance measures were used by the Federal Energy Regulatory Commission (FERC) to evaluate parameters of a solid flame model17. Except Safety Factor (SF), the two models satisfied the FERC criteria for other statistical performance measures. Safety Factor (SF) was more than 2 for both cases, because a large emissivity ε was selected on purpose to have a slight overestimation on thermal radiation to ensure safety. The second model using Eq. (3) to calculate atmospheric transmissivity had the same performance for Factor of Two, but a better prediction performance in terms of other statistical performance measures. Also, both models overestimated the radiation for Test 18 as shown in Figure 8, this can probably be explained by the fact that Test 18 used the smallest propane flow rate among all tests, which made Test 18 more vulnerable to the environmental conditions.



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Figure 8 Thermal radiation prediction using solid flame model, left: τ=1, right: τ was calculated using Eq. (3) (empty square: results from Test 18) Table 5 Statistical performance measures for selected parameters Statistical performance measures Safety Factor (SF) Factor of Two (FAC2) Mean Relative Bias (MRB) Geometric Mean Bias (MG) Mean Relative Square Error (MRSE) Geometric Variance (VG) a

Expressiona 0.5 〈

〉 2.0

2.0 " 50% $ 〉 0.4 $0.4 〈 1 & ' ( 2 0.67 *+ 〈ln 〉 1.5 & $ (. 〈 〉 2.3 1 & ' (. 4 . *+ 〈/ln 0 〉 3.3

! 0.5

Flame T=1300 K, ε=0.45, τ=1

Flame T=1300 K, ε=0.45, τ obtained using Eq. (3)

2.31

2.17

0.89

0.89

-0.26

-0.22

0.74

0.86

0.23

0.22

1.50

1.47

Cc is the calculated value, Cm is the measured value

3.3.3 Surface emissive power Surface emissive power (E) can also be obtained through Eq. (1) and Eq.(3) with known radiation measurement (I). The cylinder shape was used to calculate the view factor. Gómez-Mares proposed a power correlation for surface emissive power against flow rate or flame length7. The power correlation ensures a zero value of surface emissive power when the flame length is zero, which cannot be satisfied by the previous linear correlation7. The correlations in this work are shown in Figure 9 and Figure 10, which used the average surface emissive power calculated from seven measurements of different locations. The data are scattered, which is believed to be common for large14 ACS Paragon Plus Environment

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scale tests. Similar coefficients for power correlations were obtained compared with the results reported by Gómez-Mares and Sonju7. A similar correlation was proposed in this study for surface emissive power against the flame area (rectangle) as shown in Figure 11.

Figure 9 Surface emissive power with flow rate

Figure 10 Surface emissive power with flame length (empty circle: vapor release; solid circle: liquid release)



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Figure 11 Surface emissive power with flame area (empty circle: vapor release; solid circle: liquid release) 3.3.4 Fraction of heat radiation A portion of the heat from the burning fuel was irradiated. The fraction of heat radiation (η) is the percentage of the radiative heat (R) to the total heat (Q) as shown in Eq. (4). The radiative heat was obtained by the product of average surface emissive power and surface area of the flame cylinder. The total heat was the product of the combustion heat of propane and the flow rate. 1 = 2 ⁄3

(4)

R = 5 678

(5)

(6) Q = : 5 In this work, the average fraction of heat radiation was 0.102 with a minimum of 0.054 and a maximum of 0.238 as shown in Figure 12. The fraction of heat radiation was found to be subject to the fuel’s exit velocity and other conditions16,18,19. The fraction of heat radiation decreases with increasing fuel exit velocity, since high exit velocity enhances combustion and a less luminous blue flame is produced. The fraction of heat radiation followed the same trend in this work. The high exit velocity produced low η value flame. Markstein reported η values ranging from 0.204 to 0.246 for low exit velocity flames ranging from 0.22 m/s to 5.10 m/s20. Gómez-Mares reported an average η value of 0.07 for high exit velocity (sonic) flames7. The current work had an exit velocity ranging from 25 to 210 m/s, which can be considered as middle exit velocity.


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The η values were between those reported by Gómez-Mares and Markstein, which is consistent with the range of propane exit velocity.

Figure 12 Fraction of heat radiation

4 Conclusions This work studied propane jet fires ejected both vertically and horizontally.

The

visualization of the jet flames used both CCD and infrared cameras and identified that a cylindrical shape was a good description of vertical and horizontal jet fires. For the vertical fires, a correlation was developed for thermal radiation against distance from the flame axis. For horizontal fires, the effects of vapor flow rate on flame geometry and thermal radiation were studied. It was found that a high flow rate increased thermal radiation at a given position. However, it was also found that the thermal radiation could not be described by a correlation with distance from the flame axis for a horizontal fire of a given flow rate. The solid flame was used with selected parameters, which were evaluated by statistical performance measures.

The surface emissive power was

obtained using the solid flame model based on the radiation measurement. The surface emissive power was used to developed correlations with flow rate, flame length, and area. The fraction of radiation was found to be 0.102, which was consistent with the range of flow rate.



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5 Acknowledgements The authors would like to acknowledge General Monitors, Inc. for their assistance in this research. The authors would also like to acknowledge the Mary Kay O’Connor Process Safety Center for sponsoring this research.

References (1)

Paé-Cornell, M. E. Learning from the Piper Alpha Accident: A Postmortem Analysis of Technical and Organizational Factors. Risk Anal. 1993, 13, 215.

(2)

Casal, J.; Mares, M. G.; Muñoz, M.; Palacios, A. Jet Fires : A “ Minor ” Fire Hazard ? Chem. Eng. Trans. 2012, 26, 13.

(3)

Proust, C.; Jamois, D.; Studer, E. High Pressure Hydrogen Fires. Int. J. Hydrogen Energy 2011, 36, 2367.

(4)

Schefer, R. W.; Houf, W. G.; Williams, T. C.; Bourne, B.; Colton, J. Characterization of High-Pressure, Underexpanded Hydrogen-Jet Flames. Int. J. Hydrogen Energy 2007, 32, 2081.

(5)

Lowesmith, B. J.; Hankinson, G. Large Scale High Pressure Jet Fires Involving Natural Gas and Natural Gas/hydrogen Mixtures. Process Saf. Environ. Prot. 2012, 90, 108.

(6)

Palacios, A.; Muñoz, M.; Darbra, R. M.; Casal, J. Thermal Radiation from Vertical Jet Fires. Fire Saf. J. 2012, 51, 93.

(7)

Gómez-Mares, M.; Muñoz, M.; Casal, J. Radiant Heat from Propane Jet Fires. Exp. Therm. Fluid Sci. 2010, 34, 323.

(8)

Kiran, D. Y.; Mishra, D. P. Experimental Studies of Flame Stability and Emission Characteristics of Simple LPG Jet Diffusion Flame. Fuel 2007, 86, 1545.

(9)

Sonju, O. K.; Hustad, J. E. An Experimental Study of Turbulent Jet Diffusion Flames. In Dynamics of Flames and Reactive Systems; Progress in Astronautics and Aeronautics; American Institute of Aeronautics and Astronautics, 1985; pp. 320– 339.

(10) Mcgrattan, K. B.; Baum, H. R.; Hamins, A. Thermal Radiation from Large Pool Fires; 2000.


Page 18 of 19

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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(11)

Brzustowski, T. A.; Sommer, E. C. Predicting Radiant Heating from Flares. In Proceedings of Division of Refining, American Petroleum Institute; Philadelphia, PA, USA, 1973; Vol. 53, pp. 865–893.

(12)

View Factor, 2015, https://en.wikipedia.org/wiki/View_factor.

(13)

Palacios, A.; Casal, J. Assessment of the Shape of Vertical Jet Fires. Fuel 2011, 90, 824.

(14)

Laboureur, D.; Zhang, B.; Liu, Y.; Gopalaswami, N.; Mannan, M. S. Experimental Study on Propane Jet Fire Hazards: 1. Assessment of the Main Geometrical Features of Horizontal Jet Flames. In Mary Kay O’Connor Process Safety Center International Symposium; College Station, TX, USA, 2014.

(15)

Howell, J. R.; Menguc, M. P. Chapter 7 Radiation. In Handbook of heat transfer; McGraw-Hill: New York, US, 1998.

(16)

Chamberlain, G. A. Developments in Design Methods for Predicting Thermal Radiation From Flares. Chem. Eng. Res. Des. 1987, 65, 299.

(17)

Federal Energy Regulatory Commission. Recommended Parameters for Solid Flame Models for Land Based Liquefied Natural Gas Spills; 2013.

(18)

Brzustowski, T. A.; Gollahalli, S. R.; Gupta, M. P.; Kaptein, M.; Sullivan, H. F. RADIANT HEATING FROM FLARES. ASME Pap [ASME Pap]; Aug 11-13 1975.

(19)

McCAFFREY, B. J. Momentum Diffusion Flame Characteristics and the Effects of Water Spray. Combustion Science and Technology, 1989, 63, 315–335.

(20)

Markstein, G. H. Radiative Energy Transfer from Turbulent Diffusion Flames. Combust. Flame 1976, 27, 51.


Experimental Study on Propane Jet Fire Hazards: Thermal Radiation

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