Flames clear

Alcohols.—Bums rapidly with a clear flame. Typical of many aliphatic substances. 

Factors affected by the rate of pressure increase in a given space and for a given amount of energy include the pressure reached at equilibrium per unit amount of substance, and the reaction rate (or deflagration rate). The improved time/pressure test method is considered to be the test method that satisfies both constraints. In the case of having a clear flame front like KCIO 3 /cellulose mixtures, the deflagration rate can be obtained by the method discussed above. 

Figure 10 Photographs of the flame tunnel, with the control panel at the right hand side, and the flame tunnel in the middle. The burner is located at the top (not shown). At the flont side, the three injection nozzles for CEB material are visible. Through the opening in the mid e, the clear flame from diesel ts visible (right).

Heated with a larger quantity of dry caustic baryta, it partially fuses, appears to become a hydrate, evolves ammonia, and then distills over a colorless, oily body, deserving notice.It is lighter than water, in which it is insoluble. It possesses an aromatic, sweetish taste not unlike that of fluid chloride of carbon (C C/s) and discovers itself particularly by its almost sugar-sweet tasted This oil bums with a clear flame, and is changed neither by caustic alkali nor by acids even potassium may be melted in it by gentle warmth without change. 

There are two origins of radiation from products of combustion to solids (1) radiation from clear flame and from gases and (2) radiation from the micron-sized soot particles in luminous flame. 

The merits and debits of clear flames versus long luminous flames have been debated by engineers for years. Modified burners and control schemes are helping to utilize the best of both. A problem common to many burner types is change of the flame characteristic as the burner input is turned down. 

Problems with some clear flame burners are (1) movement of the hump in the temperature profile closer to the burner wall as the firing rate is reduced and (2) at lower input rates, temperature falls off more sfeeply at greater distances from the burner wall (e.g., the temperature profile of a burner firing at 50% of its rated capacity... 

Trinks and Mawhinney s 5th Edition mentions heating more load per unit of hearth area by alternating short-flame and long-flame burners. Prior to that, one of Professor Trinks countrymen, Dipl. Ing. Otto Lutherer, Chief Engineer of North American Mfg. Co., dreamed of being able to increase the heat flux to a furnace load by alternating luminous and clear flames in furnaces. 

Mr. Lutherer reasoned that the opaque soot particles in luminous flames would increase radiation to furnace loads and refractory crown, and that if clear flames then momentarily replaced them, that would allow the refractory to radiate to the load and dump its accumulated high-thermal-head heat on the load. 

Direct gas (and clear flame) radiation from triatomic gas molecules (mainly CO2 and H2O) to surfaces of loads and walls that they can see ... 

Mischutin V. Apphcation of a clear flame retardant fmish to fabrics. J Coated Fabrics 1993 22 234-52. 

Nevertheless, some authors have provided some evidence of a flame inhibition effect of phosphorus. Schartel et al. have measured the EHC of epo y resins in a PCFC i.e. corresponding to complete combustion) and in a cone calorimeter. Epojy resins containing DOPO covalently linked to the network have been studied. All thermosets exhibited the same EHC in a PCFC (approximately 24 kJ g ), but in cone calorimeter tests the composites prepared from the phosphorus-containing resins (with 60 vol% of carbon fibers) exhibited a significantly lower EHC than the composite prepared from the phosphorus-free epoxy resin. In this study, a clear flame inhibition effect was evidenced. 

An unaccelerated, clear, flame retardant resin meeting the M2 classification, suitable for hand-lay and RTM. ... 

The addition of TMP to flames reduces the maximum concentration of H atoms in the chemical reaction zone of a flame. Figure 7 shows the relative reduction in the maximum concentration of H atoms A[H]max (A[H]max=l-[H]d ax/[H]Omax) and OH radicals A[OH]max (A[OH]max=l-[OH] max/[OH]Vax) due to the addition of TMP versus ( ), obtained from structure simulations for freely-propagating flames without additives and with 0.04% TMP added. Where [Hjmax and [OHjmax - maximal concentrations of H and OH in the flame zone, subscripts "d" and "0" are related to doped and clear flames respectively. It is evident from Figs. 6 and 7, that there is a correlation between the dependences of F and A[H]max and A[OH]max on ( ) and D. 

---