Burner domestic

Liquid fuels. Industrial burners for liquid fuels usually atomize the fuels in hot air so that droplets will evaporate during combustion. For more volatile fuels such as kerosine, vaporizing burners of various types are employed, usually for domestic purposes. 

In a general manner, diesel engines, jet engines, and domestic or industrial burners operate with lean mixtures and their performance is relatively insensitive to the equivalence ratio. On the other hand, gasoline engines require a fuel-air ratio close to the stoichiometric. Indeed, a too-rich mixture leads to an excessive exhaust pollution from CO emissions and unburned hydrocarbons whereas a too-lean mixture produces unstable combustion (reduced driveability and misfiring). 

For other physical properties, the specification differences between diesel fuel and home-heating oil are minimal. Note only that there is no minimum distillation end point for heating oil, undoubtedly because tbe problem of particulate emissions is much less critical in domestic burners than in an engine. 

The desired air—fuel volume ratio is usually seven or more, depending on the stoichiometry. Burners of this general type with many multiple ports are common for domestic furnaces, heaters, stoves, and for industrial use. The dame stabilizing ports in such burners are often round but may be slots of various shapes to conform to the heating task. 

Insiilating refractories are used mainly in the heat-treating industiy for furnaces of the periodic type. They are also used extensively in stress-relieving furnaces, chemical-process furnaces, oil stills or heaters, and the combustion chambers of domestic-oil-burner furnaces. They usually have a hfe equal to that of the heavy brick that they replace. They are particularly smtable for constructing experi-... 

This principle is confined to domestic applications where kerosene or premium gas oil is concerned. The simplest type uses a number of concentrically arranged wicks which promote vaporization of kerosene into an air/vapor mixing zone enclosed within a perforated dmm arrangement. Normally, these burners obtain their air by natural draft. 

These are otherwise known as atmospheric or premix burners. Primary air is entrained into the gas stream prior to exit from the nozzle. The best known of these types is the Bunsen burner, and the most common is the ring-type domestic cooker hob arrangement. Both aerated and non-aerated types are often found in a bar configuration. Typical applications are heating of tanks and process uses involving direct heating of the product. Figure 24.9 shows a typical aerated bar burner. 

Some application areas of gas sensors are described in chapter 5.3, including gas and fuel powered domestic burner control, air quality sensing, indoor detection of CO, and natural gas detection. Several further applications of gas sensors are still in the development stage, e.g. for cooking and frying control, or for controlling the self-cleaning procedure (pyrolysis) of ovens. 

In Chapter 5.4, optical ultraviolet radiation sensors are described, including UV-enhanced silicon-based pn diodes, detectors made from other wide band gap materials in crystalline or polycrystalline form, the latter being a new, less costly alternative. Other domestic applications are personal UV exposure dosimetry, surveillance of sun beds, flame scanning in gas and oil burners, fire alarm monitors and water sterilization equipment surveillance. 

Domestic Burner Control (Fuel Burners, Gas Condensing Boilers)... 

Finally, it is of interest, not only to the student of industrial archelogical history, but also to the modern technologist, to refer to coal gasification. A few decades ago the gasification of coal provided a means of supplying communities with coal gas, a mixture of hydrogen, methane and carbon monoxide, which could be ignited in burners and used as a domestic or industrial source of heat. With the discovery of natural gas... 

Twenty-five years ago the domestic fuel oil business was no more than a healthy infant in fact, if we go back another five years, we are hardly aware of its existence. But in 1926 the 200,000 domestic oil burners in this country consumed 9,715,000 barrels of fuel oil, or about 1.1% of the crude petroleum run to stills. The oil burner was recognized as here to stay, and the oil industry was giving quite a bit of thought to its future. That thought was justified. As of the end of last year (1950) there were 5,146,354 domestic oil burners, and they consumed during the year 228,000,000 barrels of fuel oil, or 11% of the crude petroleum run. The infant has really grown up (Figure 1). 

The three principal fuels for domestic central heating systems are coal, fuel oil, and gas. The growth of fuel oil has been mostly at the expense of the hand-fired coal furnace. One of the main attractions of fuel oil was automatic heat, and the automatic coal stoker was for a time a lively competitor. Lately its popularity has very much declined. Within recent years the extension of natural gas lines has resulted in increased popularity for gas heating, and in 1950 the sales of gas burners actually surpassed the sales of oil burners, as shown by the following percentage figures on sales of automatic heating equipment gas burners, 56.3% oil burners, 42.6% and automatic stokers, 1.1%. 

Under the 1948 commercial standard CS 12-48, fuel oil No. 1 is defined as intended for vaporizing pot-type burners and other burners requiring this grade, whereas No. 2 is defined as for general purpose domestic heating for use in burners not requiring No. 1. The No. 1 fuel is therefore specified to have a low 10% point in the ASTM distillation to ensure quick starting, and a low end point and low carbon residue to ensure clean vaporization. 

Fuel oil No. I is also a high grade Diesel fuel and has to compete with its use for that purpose. Furthermore, it is also an excellent cracking stock and therefore competes with gasoline. The question of how popular it will remain is consequently entirely one of economics, and certainly the burner that can handle all qualities of No. 2 has a distinct economic advantage over that requiring No. 1. In 1950, fuel oil No. 1 represented 16% of the total domestic fuel oil business. 

No. 2 Fuel oil also called domestic heating oil has properties similar to diesel fuel and heavy jet fuel used in burners where complete vaporization is not required before burning. 

Turbulent combustion is encountered in most practical combustion systems such as rockets, internal combustion or aircraft engines, industrial burners and furnaces, while laminar combustion applications are almost limited to candles, lighters and some domestic furnaces. Studying and modeling... 

For continuous melting of domestic and technical glass, small electric furnaces have been developed a longitudinal cross section of one such type is shown in Fig. 102. At the working end, the temperature is controlled by resistance heating elements. The direction of melt flow is shown by the arrow. All-electric furnaces have to be heated up by auxiliary gas burners since the cold batch does not conduct electrically. 

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