Burnout test

F. Tubvtlar Channel Burnout Tests - Small Scale Heat Throughput Loop - R. J. Weatherhead... 

The burnout tests run with water flowing upward in a 0.306=in, ID nickel tube and with net steam generation at the tube exit have been com= pleted. The following range of variables was covered ... 

ASTM D2584 Ignition Loss - This is commonly called the burnout test, whereby the filled or reinforced plastic is ignited to 565°C until the polymer... 

Aladyev et al. (A4) refer to specific tests using two tubes with wall thickness of 0.016 and 0.079 in., and they report no noticeable effect on the burnout flux, but details of the tests are not given. Lee (LI) examined the question of wall thickness using two uniformly heated tube lengths with water at 1000 psia, and his results for a mass velocity of 1.5 x 106 lb/hr-ft2 are shown in Fig. 15. It can be seen that with the 68-in. tube there is no difference between a wall thickness of 0.034 in. and a thickness of 0.082 in. With the 34-in. tube, however, the thicker wall gives about 7 % higher burn-out flux values at low... 

Producing burn-out correlations would appear to be almost a pastime Milioti (Ml2), for example, was able to compile a total of 59 different burnout correlations, and the number still grows. Most of these correlations are based on very restricted ranges of system parameters, however, and although they work well within the restrictions, they usually deviate markedly on extrapolation. Some of the earlier correlations are also readily seen to be inconsistent with now well-established experimental facts, even simple though important facts such as the linear or nearly linear relationship between and Ah. As mentioned earlier, the hypothesis-testing technique exploited by Barnett is a very effective tool for showing up defects, and the method has... 

H3. Hesson, G. M., Fitzsimmons, D. E., and Batch, J. M., Experimental boiling burnout heat fluxes with an electrically heated 19-rod bundle test section, BNWL-206 (1965). 

Stevens, G. F., and Wood, R. W., A comparison between burnout data for 19-rod cluster test sections cooled by freon-12 at 155 psia, and water at 1000 psia in vertical upflow, AEEW-R.468 (1966). 

At present there is no small-scale test for predicting whether or how fast a fire will spread on a wall made of flammable or semiflammable (fire-retardant) material. The principal elements of the problem include pyrolysis of solids char-layer buildup buoyant, convective, tmbulent-boundary-layer heat transfer soot formation in the flame radiative emission from the sooty flame and the transient natme of the process (char buildup, fuel burnout, preheating of areas not yet ignited). Efforts are needed to develop computer models for these effects and to develop appropriate small-scale tests. 

Inlet parameter concept CHF correlations based on the inlet enthalpy must be accompanied by a length term to predict the CHF in test sections of various lengths, as shown in Figure 5.56, where Ai represents the inlet enthalpy (AHm). The predicted burnout conditions shown in the figure are based on Becker s correlation (Becker et al., 1973) ... 

Griff el, J., and C. F. Bonilla, 1965, Forced Convection Boiling Burnout for Water in Uniformly Heated Tubular Test Sections, Nuclear Structural Eng. 2.1-35. (5)... 

Hesson, G. M., D. E. Fitzsimmons, and J. M. Batch, 1965, Experimental Boiling Burnout Heat Fluxes with an Electrically Heated 19-Rod Bundle Test Section, BNWL-206, Battelle Northwestern Lab., Richland, WA. (3)... 

Ivey, H. J., and D. J. Morris, 1965, The Effect of Test Section Parameters on Saturation Pool Boiling Burnout at Atmospheric Pressure, AIChE Chem. Eng. Prog. Symp. Ser. 67(60) 157—166. (2) Jacket, H. S., J. D. Roarty, and J. E. Zerbe, 1958, Investigation of Burnout Heat Flux in Rectangular Channels at 2000 psia, Trans. ASME, J. Heat Transfer 50 391. (5)... 

In studying compatibility of oxidizers, both static and dynamic tests are conducted. An oxidizer such as chlorine trifluoride is particularly troublesome under flow conditions, although it can be stored under static conditions rather easily because of the firm fluoride film it forms. If this film is cracked so that continuity no longer exists, burnout under high flow conditions can occur. 

A tile stove heating insert, illustrated by Figure 5, with a thermal capacity of 10 kW, representing the state of the art of wood log combustion systems was selected as a test stove. The firing principle of the stove can be described as "backside downdraft". It consists of two spatially separated, well insulated reaction zones for gasification of the wood fuel and burnout of the combustible gases, respectively. 

In the following, experimental results of gas concentration measurements at the positions 6, 9 and 11 wilt be shown and discussed. All measurements are done at nominal heat output using suction probes covering the whole depth of the burnout zone. During one test bum cycle the suction probe remains at one position in order to get information about the course of gas composition and temperature at the particular measuring position. 

In order Co get reliable data, results of several bum cycles are used to calculate mean values of velocities and turbulence intensities. In addition to the mentioned investigations by LDV, gas concentration measurements of CO2, CO, O3 and hydrocarbons (CHj) are done at the inlet of the burnout zone. Temperature measurements are carried out for the entering combustible gases, the added burnout air and at two wall sections in order to get complete data sets characterising the combustion conditions in the investigated test stove during the different burn phases of wood log combustion. 

The rebum test runs have been performed under constant conditions in the combustion reactor. Besides the wall temperature (1300 °C) the hiel, the fUel feeding rate, and the probe positions stayed unchanged. The hard coal G ttelbom was burnt in the main combustion zone at an air ratio of 1,15. The fuel feeding rate amounts to 1 kg/h. The position of the burnout air probe remained unchanged. It was adjusted to a calculated residence time of 1 n /h pyrolysis gas of 2 s in the reduction zone. Those settings (residence time, wall temperature) have been proved to be optimal for rebuming in earlier projects [7, 8]. Only the burnout air was varied in order to get a constant O2 concentration of 3 % in the flue gas. 

The activity was also tested where char combustion was conducted in the regenerator. The average conditions for this run are given in Table VI. In this run 32 lbs. of char were burned, thereby exposing the acceptor to 0.73 lb. ash/lb. MgO CaO inventory. The combustion was trouble free, giving essentially flat temperature profiles and complete burnout of the carbon. No ash fusion difficulty was experienced. 

A safety test was made at PSC to demonstrate that a microbridge overvoltage burnout does not ignite a stoichiometric gas-air mixture. The mieiobridge ehips were placed in a premixed (0.8 stoichiometiy) gas air... 

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