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Natural gas quality assessment is a relevant issue. A critical analysis of calorimeter designs for measuring the calorific value of natural gas was carried out. The most common methods for determining the calorific value of natural gas are as follows: direct by gas calorimeters; indirect by gas chromatographs; indirect, based on correlations. The advantages of isoperibolic calorimeters of measuring calorific value of natural gas directly in the consumer’s conditions are substantiated. The design of a portable calorimeter containing a thermostated shell, calorimetric tank, Peltier element with tank, circulating pump, gas burner, thermostat systems, metered supply of natural gas and air, fuel ignition, sensors, combustion analyzer and control and measurement unit, was developed. The geometric dimensions of the calorimetric tank are optimized, materials and technologies of manufacturing parts are specified. The metrological analysis of the developed portable calorimeter was carried out. A method for measuring the calorific value of natural gas directly in the conditions of household consumers and transport enterprises was developed. The results of testing the prototype calorimeter in the laboratory confirmed its high performance and metrological characteristics, and the deviation of the measurement of the calorific value of natural gas from that determined using a gas chromatograph was 0.6%.

Experimental investigations of a new burner for gas ranges have been conducted. We present a modified construction diagram of a burner with a new heat-transfer intensifier in the form of tapered-screw fins on the surface of a metal rod that has shown its efficiency and made it possible to raise the cost effectiveness of natural gas combustion compared to a base burner.

Cooking is an important domestic activity requiring energy. Traditionally, solid fuels, like firewood and charcoal, are used as the resources for supplying energy for cooking. However, burning of solid fuels inside the households causes indoor pollution and adversely affects the health of the users and other occupants. Various governmental and world bodies, like the UN, encourage people to shift from the traditional fuels to clean and sustainable options, of which gaseous fuel is an important one. Natural gas and liquefied petroleum gas (LPG), which are used for domestic cooking, are fired in gas burners designed for the cookstoves. Though the use of gaseous fuels lowers the household air pollution, early domestic gas burners were low in thermal performance with efficiency value of around 40%. Continuous research and development in the design and analysis of the stoves have led to a significant improvement in the thermal performance of commercial gas burners yielding efficiency exceeding 65%. Efforts are still on to improve the thermal and emission performance of the burners further without sacrificing user comfort and flexibility through innovative designs. This article presents a review on the design, development, and technological advancements in the gas burner technology for domestic stoves, and analyzes the effects of various parameters on their thermal and emission performance.

Ignition within gas burner ejectors can lead to off design conditions and has significant influence on the burner behavior. Thus ignition in the ejector should be prevented. In the present study the influence of combustion reactions on the performance of gas burner injectors is investigated. To investigate if ignition is possible, simulated ignition delay times, using a detailed reaction mechanism, are compared to predicted mean residence times of the gas in the ejector. Gas burner ejectors are designed using one dimensional analytic equations, based on energy and momentum conservation equations and conventional isentropic equations. 1D results are compared to 2D computational fluid dynamics (CFD) simulations, to take into account non-ideal mixing effects along the ejector. Results are validated with experiments with air at room temperature. 1D results show very good agreement not only with CFD simulations for the case of non-reactive flows, but also with performed experiments. It is shown that the assumption of ideal mixing along the ejector and thus the comparison of the ignition delay time to the gas mean residence time, to predict ignition in the ejector, is not valid. Ignition in the ejector is possible, even if the ignition delay time is more than thirty times higher than the mean residence time. In addition to that, it is shown, that ignition and the choice of reaction mechanism have significant influence on the predicted gas burner ejector performance. Thus, the accurate prediction of ignition delay time and the use of a detailed reaction kinetic are mandatory to correctly predict the burner ejector behavior.

The paper presents results of theoretical numerical research dealing with CO and NOx emission performed in the process of optimization of the performance of low-power atmospheric burners. The theoretical part of this paper, whose main goals were better understanding of the complex issues of methodology and establishment of performance prediction and optimization of low-power atmospheric gas burner included numerical variation of independent parameters, such as burner geometry, the coefficients of primary and secondary air and different gaseous fuels including biogas. The findings of theoretically obtained performance prediction and optimization of atmospheric burners were experimentally investigated in purpose built test rigs for a number of variable parameters. The obtained results fully justified the proposed models of performance prediction and burner optimization.

Studies have been carried out on the purification of biogas from sulfur compounds, carbon dioxide and water vapor for subsequent use in micronizer burners. The possibility of bringing it to the parameters of natural gas of the following composition: methane (CH4) – 85 % vol., carbon dioxide СО2 – 11 % vol., water vapor – 9 mg/m3, hydrogen sulfide H2S - 20 mg/m3 with minimal energy costs for its preparation is demonstrated. The basic relationships are obtained for assessing the design and technological parameters of the infrared radiation burners operation. Experimental studies of the flame stability limits on perforated ceramic nozzles have shown that flashback through them is possible when the thermal power is increased to a certain critical value. In this case, the thermal power depends on the type of gas and the air content in the combustible mixture. The heat balance equations have been derived to optimize the designs and operation modes of infrared radiation burners. The design of 40 gas burners was improved by changing the geometric dimensions and shape for a uniform distribution of biogas supplied and sustainable combustion over the entire area of the burner. It was established that the temperature of the heating surface of the GIK-8 burner on gas mixtures with a CO2 content of 18-34 % is 900-950 ° C, which does not differ from the nominal temperature when operating on natural gas. The infrared heating system was modernized, adapted for burning purified biogas with methane content up to 98 %, in particular, the biomethane feed and control system, the additional biogas input system, and the automatic burner control system were improved.

The results of an experimental study of a new gas burner that can be effectively used in domestic gas stoves are presented. The presented modified design of a burner with new heat-transfer enhancers made it possible to reduce heat loss to the environment and increase the efficiency of burning natural gas.

This paper presents the results of an experimental study on the combustion process of methane mixed with NH3 in flameless mode. At a time of striving for CO2-free power, NH3 became a potential energy storage carrier fuel from renewable sources. Flameless combustion features low emissions and is a very efficient technology used in the power sector, as well as steel production, ceramics, etc. Industrial furnaces were tested in the context of pure methane combustion with an addition of NH3, up to 5%. Flameless combustion conditions were achieved with a regenerative gas burner system (high regenerative system). The burner consists of four ceramic regenerators allowing for continuous preheating of air, even up to 50 K lower than the temperature of the combustion chamber wall. Constant power of the introduced fuel was kept at 150 kW and the fuel-air equivalence ratio ranged from 0.75 to 0.95. The results have shown a growth of molar fraction of NO in flue gases when NH3 content in the fuel rose. The increase is more significant for the tests with a higher amount of oxygen in the combustion chamber (a lower fuel-air equivalence ratio). An addition of 5% of NH3 into the fuel caused an emission of NO at the levels of 113 ppmv and 462 ppmv (calculated to O2 = 0%), respectively for low and high fuel-air equivalence ratios.

On the basis of gas-burning devices of the GS series, new devices have been developed, in which gas channels are installed for operation in the mode of maximum or minimum flame length. This allows to increase the stability of the flame at low temperatures of the working space (below the natural gas ignition temperature), which in turn provides an increase in the economic performance of the tunnel kiln firing ceramic bricks. Bibl. 5, Fig. 2.

In climate regions with large seasonal variations in solar radiation, such as the Pacific Northwest of the United States, a solar thermal energy collector might not economically satisfy year-round domestic water heating demands, requiring an auxiliary unit, such as a natural gas-fired water heater. Previous studies have shown that the burner efficiency of a gas-fired water heater varies depending on the log-mean temperature difference between the cold fluid (water) and the hot fluid (combustion gases). In a solar/gas hybrid water heating system, where solar collectors are used in conjunction with a gas-fired heater, the partial heating of water provided by solar input reduces the log-mean temperature difference value for the gas heater, reducing the efficiency of the gas burner. Since this efficiency reduction varies depending on the amount of pre-heating provided by solar energy input, it is difficult to accurately predict the actual cost and energy savings offered by solar/gas hybrid water heaters in different climates and operation scenarios. Hence, to predict the actual energy and cost savings under various design conditions, the performance of solar/gas hybrid systems must be better understood. The objective of this work is to experimentally determine the thermal performance of a solar/gas water hybrid water heating system with a 6.44 m2 flat plate solar collector array and a 22.3 kW natural gas burner in Corvallis, Oregon, USA. Under different temperature lifts and solar insolation values, the system was operated at three different modes of heating: solar, gas, and combined solar/gas mode. The overall system thermal efficiency value for each mode is calculated. The efficiency of the solar collector heating system was found to be 41.97%, 39.82%, and 35.05% at initial water temperature of 20, 30, and 51.5 °C, respectively. For initial water temperatures of 20, 30, and 51.5 °C, the efficiency of the gas burner was found to be 69.2%, 66.4%, and 65.5% at the HHV, and 76.7%, 73.6%, and 72.6% at the LHV of natural gas, respectively. In the combined solar/gas heating mode, the efficiency of the gas burner decreased with increasing solar fraction. For solar fractions of 4.93%, 9.40%, 11.39%, and 14.27%, the efficiency of the gas burner in terms of the HHV of natural gas was found to be of 69.08%, 66.80%, 66.17%, and 65.18%, respectively. Based on the experimental results, a configuration that would provide higher overall system efficiency for combined solar/gas heating is suggested.

Nowadays, people are having a hectic schedule and hence sometimes unconsciously forget to turn off their gas burner in the kitchen. A significant amount of gas is being wasted. This system's fundamental goal is to develop a device for kitchen safety and reduce gas wastage, which concentrates on additional protection. This paper proposes an approach to automatically prevent any threat from the usage of the gas stove. This system is an ATmega328p microcontroller-based that deals with turning off the kitchen gas valve mechanism in various situations. It turns off the gas supply when it is not used for cooking purposes utilizing a solenoid valve. The gas burner will turn on when there must have a flame in the gas burner and a cooking pot on the gas burner. When smoke is detected, the temperature is high from its range, and there is any kind of unnecessary gas amount in the kitchen, then the exhaust fan will turn on automatically. Like a micro oven, there is also a timer system for cooking purposes at a particular time. Here also include a Bluetooth system for controlling the burner by voice. If there any gas leakage is detected, the system will make an alarm and inform the house owner by calling and sending a text. Also, there are various modes involved in this system. It highlights the provision for kitchen safety. It greatly assists in securing safety and making use of gas stove more convenient and easy.

The combustion effect of natural gas-air mixed combustion is optimised through an effective and rational design of the burner structure, thereby reducing the emission of atmospheric pollutants and achieving energy saving and emission reduction. This paper starts from the geometric model of the burner and uses Computational Fluid Dynamics (CFD) technology to numerically simulate the combustion distribution in the burner, which results in the combustion distribution of the burner after optimising the structure. The guiding effect of the blower guide vanes on the airflow is weak, and the back pressure effect of the guide vanes mounting body is significant, which reduces the primary air volume and prolongs the combustion history in the central region of the flame; The temperature field is evenly distributed and the combustion is well distributed; CH4 and CO in the furnace chamber are basically burned out and the NO concentration in the furnace chamber is about 800 ppm, which basically meets the emission standard and the combustion effect is good. This paper has certain guiding significance for the study of burner structure.

Reinforced concrete (RC) submerged floating tunnels (SFTs) represent a possible solution for crossing wide, deep fjords, and is considered for the E39 highway route along the Norwegian west coast. With regard to SFTs, the specific accidental scenario that is under investigation is the combined action of fire and subsequent internal explosion, as this is a crucial safety design condition for this type of structure. To assess the structural performance of reinforced concrete structures under combined fire and blast actions, gas burner equipment and a shock tube device were used to generate high temperature and blast loading, respectively, on RC circular slabs. A proper set of instruments consisting of thermocouples embedded in the specimens, accelerometers and ultrasonic pulse velocity (UPV) equipment made it possible to capture the behaviour of the slabs under the combined fire and blast actions and to distinguish the specific role of fire and blast. Simplified numerical tools such as an equivalent elastic single degree of freedom (SDOF) model and a linear elastic finite element (FE) model were used to interpret the experimental results. By considering all combinations of three fire exposure times and two shock waves, the effect of damage accumulation from a combined action of fire and subsequent internal explosion was mapped. A reliable benchmark for numerical models was obtained.

One of the main methods used to generate thermal energy is the combustion process. Burners are used in both industrial and residential applications of the open combustion process. The use of fuels that reduce polluting gas emissions and costs in industrial and residential processes is currently a topic of significant interest. Hydrogen is considered an attractive fuel for application in combustion systems due to its high energy density, wide flammability range, and only produces water vapor as waste. Compared to research conducted regarding hydrocarbon combustion, studies on hydrogen burners have been limited. This paper presents the design and evaluation of an oxyhydrogen gas burner for the atmospheric combustion process. The gas is generated in situ with an alkaline electrolyzer with a production rate of up to 3 sL min−1. The thermal efficiency of a gas burner is defined as the percentage of the input thermal energy transferred to the desired load with respect to a given time interval. The experimental results show a thermal efficiency of 30% for a minimum flow rate of 1.5 sL min−1 and 76% for a flow rate of 3.5 sL min−1. These results relate to a 10 mm height between the burner surface and heated container.

The article is devoted to decision of actual task of energy saving. As a fact, a large-scale energy saving policy is being implemented in Ukraine, and energy efficiency objectives are comprehensive and cover both the legislative framework and technical innovations. It is consumed in the boiler rooms too much amount of gas. One of the effective ways to reduce energy consumption for boiler gas supply is to carry out the thermal modernization of the boiler rooms. This article describes the economic indicators of thermal renovation measures during the reconstruction of the boiler rooms. During the reconstruction of boiler rooms the following thermal modernization measures were taken for comparison: equipping the existing boiler with a modern domestic gas burner, economizer or condensing economizer; replacement of the existing boiler with a modern Ukrainian-made boiler with a modern domestic burner with the possibility of its additional equipping with economizer or condensing economizer; replacement of the existing boiler by Viessmann boiler. Conducted energy audit of the boiler room during its reconstruction has showed that the profit from the introduction of energy-saving technologies during their operation is the maximum, if it is provided the modernization of the existing boiler by its equipment at the same time modern burner domestic production and condensing economizer.

Concrete is prone to spalling when exposed to fire. During fire tests, the strains of concrete elements are hard to identify, both from the fire-exposed face and the non-exposed face. This paper presents a field experiment which employed the original CivEng digital image correlation (DIC) method developed at the Cracow University of Technology to measure the strain fields of elements exposed to heating by a pin-point gas burner. The paper presents experimental proof that it is possible to analyze the deformation of both unheated and fire-exposed sides of heated concrete by the DIC method. The strain fields, crack patterns and modes of crack development are presented. The study shows the encouraging results of employing the DIC method to test concrete behavior under fire attack.

A method for measuring local flame temperatures using a spectral-ratio pyrometer and a tomographic system based on this method are described. The theoretical substantiation of the proposed measurement method is given. A block diagram of the system containing four measuring mirrors and one multiplexing mirror is shown. The results of the computer simulation are presented, with which it is possible to estimate the error of the system depending on the number of mirrors used in it. The software developed for carrying out measurements with the maximum degree of automation under the test-bench conditions is described. The results of an experimental study using the tomographic system for measuring the field of local flame temperatures of a gas burner (in the range of 1500–2300 K) are presented. The results demonstrate the operability of the developed system.

Boilers have contributed significantly to the production of energy and other processes in industry. Understanding the combustion characteristics inside a boiler is essential to increase the efficiency and reduce environmental-related concerns. The novelty of this work is associated with a detailed analysis of the effectiveness of a developed co-firing coal-natural gas burner and the arrangements of the burners in the boiler for efficient combustion. Comparisons were made between the front-wall, the opposite-wall, and the tangential firing types. The characteristics of the flow, the coal particle motion, the temperature distribution, the concentrations of species, and NOx emission levels are examined. The results showed that each burner in the front-wall-fired type creates independent long flame zones. In an opposite-wall fired type, the flames of burners impinge upon the center of the furnace to create turbulence. Results show that front-wall and opposite-wall firing configurations exhibit hot peak zones and temperature imbalances near the furnace sidewall. This emphasizes the need for heavily swirling vanes in the main burner to shorten the flame length and mix the fuel and oxidant well for efficient combustion. The state-of-the-art tangentially fired configuration produced a fireball, ensuring thorough mixing in the furnace and allowing for the complete combustion and uniform distribution of the temperature such that NOx reduction occurs preferentially. Additionally, these results confirm the advantage of combusting coal with natural gas in the main burner, as doing so reduces NOx emissions up to 19%. The technological options identified offer potential for interested manufacturers, researchers, and others in related industries to improve the performance and reduce the emissions of industrial dual-fuel-fired combustion utilities.

Thermally efficient gas burners can be designed by optimising the parameters associated with combustion and heat transfer mechanisms. The current study presents the thermal analysis of the premixed methane-air flame jets of circular tube gas burner impinging on a target surface. The effect of flame jet parameters such as mixture Reynolds number, equivalence ratio and burner to target surface spacing on heat transfer characteristics is investigated. The thermal performance is quantified in terms of thermal efficiency. The lean and stoichiometric mixtures release maximum amount of thermal energy. However, in lean flames, a part of the energy released is used for rising the temperature of excess air. Though the combustion is incomplete for fuel rich flames, higher heat transfer is achieved because of higher flame height. The optimal thermal performance is observed when the mixture is near stoichiometric and the burner is spaced from the target surface such that the premixed cone tip just touches the surface.

A method for automatic determination of combustion regimes using flame images on the basis of a convolutional neural network on labeled data is under consideration. It is shown that the accuracy of regime classification reaches 98% on the flame images of a gas burner. The results of the operation of the convolutional neural network and classification using different linear models are compared.

The thermal radiation impact of organic peroxide fireballs is experimentally assessed using an infrared camera. Fireballs are generated while liquid peroxide filled steel drums are subjected to gas burner fire at different heating rates. Three large burning clouds are observed with varying flame characteristics. Thermal radiation properties are assessed by infrared images with the presented methods. Despite of the two-dimensional temperature fields, the flames are treated and characterized as three-dimensional objects. Fireball diameters and heights are calculated based on a representing radiating sphere with the same cloud volume. By the use of the solid flame model and assumptions for emissivity and transmissivity, heat fluxes and thermal radiation doses against distance are predicted. Thermal safety distances are presented based on the maximum irradiance and the allowed exposure time. The validation of the maximum and time-dependent radiation fields is achieved through heat flux sensors in varying distances to the fireball. The results prove the use of an infrared camera and a volume based size calculation to fully assess the thermal radiation hazards of fireballs.

Controlled gas burner experiments were conducted in single- and two-story residential style structures instrumented with pressure transducers, thermocouples, and bi-directional probes throughout the structures. Exterior doors and window openings were vented in a controlled sequence to investigate the effect of the resulting flow paths on fire-induced flow dynamics and thermal conditions in the structures. The data collected in these experiments provides validation cases for the fire modeling community which currently lacks full-scale data from experiments in realistic residential style structures. The Fire Dynamics Simulator was used to model each scenario in a validation exercise that also investigated the sensitivity of the pressure predictions to the model parameters. The model was capable of predicting the qualitative changes in pressure measurements due to ventilation events as well as the apparent elevation of the neutral plane. Peak pressures were predicted to within 6% on average and quasi-steady static pressures were predicted to within 24% on average. The mean instantaneous error between the experimental pressures and those predicted with the “Localized Leakage” method was approximately 53% compared to 67% with the “Pressure Zone Leakage” method prior to the first ventilation event.

Natural gas, when compared to other solid, liquid or gaseous fuels, offers a cleaner and more environmentally friendly combustion. Nevertheless, it also produces unwanted pollutant species such as nitrogen oxides (NOx) and carbon monoxide (CO) when fired in combustors of industrial gas turbines under high temperature and pressure. These emissions of NOx and CO are harmful for human and nature and need to be kept below the regulatory limits. This problem has been the subject of numerous research and development activities for decades. The current state of the art provides well-developed firing systems for industrial gas turbines, which ensure NOx and CO emission levels well below the legal limits [1 - 5]. A comprehensive overview of the characteristics currently available gas turbines on the German market is offered by the revised version of the ASUE brochure from 2015 in [6], where beyond the reference list about industrial and municipal gas turbines, NOx reduction methods and achieved NOx emission values are recorded. Nevertheless, there still is the need for additional research in order to contribute to both the simplification of the still complicated design of the overall combustor concepts and the further reduction of harmful emissions.

Fire whirls can be generated during large outdoor fires such as post-earthquake urban fires, and their consequences are often devastating. Therefore, when assessing the post-earthquake fire risk in urban areas, the conditions of fire whirls generation must be understood. There have been attempts to determine the critical crosswind velocity that maximizes the occurrence of fire whirls. However, it does not account for the substantially varying frequency of fire whirl generation among different cases. From a fire-risk perspective, steadily generated fire whirls need to be distinguished from intermittently generated ones, but such a distinction has not been attempted to date. In this study, the probabilistic aspect of fire whirl generation around an L-shaped gas burner in a crosswind was experimentally investigated in a wind tunnel. The test parameters were the heat release rate per unit length (32.5–86.8 kW/m) and the crosswind velocity (0.115–0.696 m/s). Fire whirl was observed in 10 out of 19 cases, but the duration period (i.e., frequency) of the fire whirl generation varied substantially among the cases. The variation of the generation frequency was successfully generalized by the Froude number, Fr, a characteristic value of the counter-flow around the fire source. The Strouhal number, St, which is often used to characterize periodic pulsation of buoyant diffusion flames, was also found to be an appropriate value characterizing the coherency within the unsteady fire whirl generation phenomena.

In order to ascertain the effects of the hydrogen addition and the primary air-fuel ratio on burner performance and emissions, we conduct tests on a commercial atmospheric gas burner using pure methane and a blend of hydrogen/methane. Relevant statistical image features are extracted from a UV–VIS camera equipped with narrow-band optical filters. Radical image results agrees with spectrometric data, showing the relevance of the OH∗ intensity radiation coming from the outer non-premixed zone. The double-cone flame structure is evident, showing a growing secondary non-premixed cone as the primary air-fuel ratio is decreased. In addition, the direct relationship found between flame radical imaging features and NOx emissions has been used to develop a predictive model by integrating classification techniques and neural networks. The research confirms UV–VIS chemiluminescence imaging techniques as powerful tools aimed at combustion monitoring, with huge prospects of being integrated within advanced emission control techniques for commercial burners.

The thermo-chemical biomass gasification is a technique by which a combustible gas called Producer Gas (PG) can be generated from biomass. The raw PG can be directly burnt in a gas burner for heating application. If PG is required to be used in internal combustion engines or to be used as a chemical feedstock for the manufacture of various chemicals, then the raw PG must to be cleaned to remove tar, particulate matter and water vapour. Many gas scrubbing methods are available to clean raw PG. Refrigeration is a method in which the raw PG is cooled to a low temperature so that the water vapour present in PG can be condensed and removed from it. Some of the volatile matter also get condensed as tar. The condensed water would wash away a certain quantity of tar and particulate matter, thus helping in their separation from the main PG stream. So, knowledge of specific humidity of PG + water vapour mixture is essential in order to properly design a refrigeration system for treating raw PG, downstream of a large scale biomass gasifier. The cooling load on the refrigeration plant can be calculated precisely from the knowledge of specific humidity of PG + water vapour mixture, mass flow rate of PG and its enthalpy. In this work, a correlation has been developed to determine the specific humidity of PG + water vapour mixture in the temperature range of 20°C - 60°C, at an absolute pressure of 1.013 bar. The composition of dry PG assumed in the present work is CO: 17%, H2: 18%, CH4: 2%, CO2: 14% and N2: 49%. The result has been compared with those of air + water vapour mixture, natural gas + water vapour mixture and martian atmosphere + water vapour mixture which are available in the literature.

Insufficient and various environmental issues of fossil fuels as the current world dominated energy is now becoming a serious global issue. The rapidly increasing demand for alternative energy sources has contributed to the steady growth of renewable energy. Owing to the fact of the abundant presence of palm kernel shell (PKS) as one of palm biomass wastes in South East Asia region, this paper investigates syngas produced from gasified PKS. The investigation is regarding its composition and combustion performance in a gas burner system. It covers emissions analysis, temperature profile and flame length. The produced syngas from downdraft gasifier was burned in the combustion chamber in air-rich and fuel-rich combustion conditions. From the experiment, the results showed that the oxidation zone temperature of above 750°C for the downdraft gasifier is suitable for producing syngas. Produced syngas can be classified as pure-carbon monoxide (CO) syngas due to 94.9% CO content with no hydrogen (H2) content and low heating value (LHV) of 10.7 MJ/kg. The wall temperature profiles for burnt syngas produced via downdraft gasification was higher with longer pattern at fuel-rich condition, which signified higher energy of syngas produced from downdraft gasifier compared to fluidised bed gasifier. The associated flame length was also longer at fuel-rich condition. Produced emission of 56 ppm NOX, 37 ppm CO and 1 ppm SO2 can still be considered as acceptable to human. It can be concluded that syngas produced from PKS shown a high potential to serve as an alternative source of energy due to its high energy content.

In this work, simulation of a premixing injection gas burner with various air temperatures with ANSYS Fluent software was performed. A natural gas fired injection gas burner was used as a heat source as a part of a thermoelectric generator. Assuming that the gas-air mixture flow is one-dimensional and axisymmetric, the issues were solved in axisymmetric setting, taking into account the gas compressibility. In the performance of a task, a set of assumptions was made: k-epsilon realizable model was picked as turbulence model with scalable wall functions; the flow in the ejector, mixing chamber and diffuser is subsonic; the pressure of the injected air was set to atmospheric pressure; pressure at the inlet to the gas burner is subcritical (≤ 86 kPa for methane). Based on the calculations, the dependence of the equivalence ratio on the air temperature was determined. Experimental researches helped develop a gas burner

Data center is an essential part of modern life that is predicted to increase both in capacity and size over the coming years. This sector consumes a significant proportion of electricity for its operation and for the essential cooling facilities. This consumption is expected to rise with increasing demands which can result in more CO2 emission. Waste heat is an inevitable by-product of DC operation with a potential of being sustainable, low cost and environmentally friendly heat source. In this paper, we proposed a novel system that integrates three thermodynamic cycles including an ORC, a HP and a Gas burner. The aim of this system is to provide cooling for the DC as well as to utilize the rejected heat to supply hot water for central heating. The results show that this system can maintain the indoor room temperature between 18-25 oC by absorbing 12 kW of heat to increase water temperature from 50 to 80 oC. In addition, the system can achieve an overall fuel-to-heat efficiency of 141.8%. Therefore, utilizing such system can have a great potential of improving DC performance as well as providing usable energy by waste heat recovery.

This paper benchmarks B-RISK’s capability to predict item ignition in multiple object compartment fire simulations. A series of fire experiments have been conducted which measured single item ignition times under the furniture calorimeter and in the ISO 9705 room. These experiments used mock-up armchair, TV and cabinetry furniture items created from three common materials found in most households in New Zealand exposed to a 100 kW gas burner flame. B-RISK uses the flux-time product (FTP) method as the criterion to predict ignition of items, based on radiation received using the point source model (PSM). This paper presents an analysis of the B-RISK predictions compared to the experimental measurements. Due to the mathematical formulation of the PSM and FTP method, it is found that the predicted ignition time is sensitive to the distance between the radiative source and the item. Predicted ignition times of armchairs constructed of polyurethane foam were within 14% of the ISO 9705 room experimental results. However, for the furniture calorimeter experiments it is found that to get reasonable predictions of the ignition times for the mock-up armchair and TV items there is a need to account for the burner flame movement by adjusting the radial distance by 10–30 mm. Direct flame contact was required to ignite the mock-up cabinetry items and B-RISK was unable to successfully predict this ignition time.

This article presents innovative method for increasing the speed of procedure which includes complex computational fluid dynamic calculations for finding the distance between flame openings of atmospheric gas burner that lead to minimal NO pollution. The method is based on standard features included in commercial computational fluid dynamic software and shortens computer working time roughly seven times in this particular case.

This paper presents a new approach to manufacture a threshold temperature sensor based on a biconical optical fibre taper. The presented sensor employs the influence of variable state of concentration of some isotropic materials like wax or paraffin. Application of the above- mentioned materials is an attempt to prove that there is a possibility to obtain a low-cost, repeatable and smart sensor working as an in-line element. Optical fibre taper was obtained from a standard single mode fibre (SMF28®) by using a low pressure gas burner technique. The diameter of the manufactured tapers was 6.0 ± 0.5 μm with the length of elongation equal to 30.50 ± 0.16 mm. The applied technology allowed to produce tapers with the losses of 0.183 ± 0.015 dB. Application of materials with different temperature transition points made it possible to obtain the threshold work at the temperatures connected directly with their conversion temperature. External materials at the temperatures above their melting points do not influence the propagation losses. For each of them two types of the protection area and position of the optical fibre taper were applied.

It is known that the Pressurized Water Reactors (PWRs), which are the most common type of nuclear reactor existing today, usually used to provide a base load electricity. In order to be able to compete with other generation types (fossil and renewables), it would be desirable to develop PWRs with flexible load following capabilities to cope with varying electricity demand, especially in deregulated markets. The thermal efficiency of PWRs can be increased by fitting the power plant with conventional fossil fuel superheaters. This hybrid system has been hypothesised to be able to adjust the power output and the cycle efficiency of PWRs. Such mode of operation would also improve the efficiency of converting the fossil fuel heat because it is applied only at the superheater stage. There are several ways to supply the heat to the superheaters, for example, by using the exhaust gas from the gas turbines and using the conventional gas burner. In this paper, the thermodynamic performance of the hybrid system (PWR with superheater) is investigated for large reactor and Small Modular Reactor (SMR) application. The thermal efficiency of the AP1000 can be improved from 30.2% to 45.8% (with CCGT), 35.6% (with gas burner), and 36.6% (gas burner with reheating). The thermal efficiency of the SMR can be improved from 33.4% to nearly 45% (with CCGT), 35.5% (with gas burner), and 37.4% (gas burner with reheating). The analysis results show that it is possible for the hybrid system to operate between 65% and the full power load.

Reduction or control of angular distortion without additional processes is demanded because it takes a lot of time and effort to correct the angular distortion of fillet-welded T-joints. In this study, the reduction or control of angular distortion of both sides of a fillet-welded T-joint by welding with trailing reverse-side gas heating was investigated through a welding experiment and its numerical simulation. First, the effect of gas heating position and intensity on the reduction in angular distortion was experimentally investigated using a gas burner. The results showed that angular distortion became smallest when reverse-side heating using the gas burner was located 50 mm backward of the welding torch. Also, the concentrated gas flame with increased propane and oxygen gas flow was effective for reducing angular distortion. It was clarified that the angular distortion could be controlled completely with an appropriate reverse-side gas heating condition. Next, the numerical simulation model of...

There is actual problem of safety control through the technological process of oil-well tubing annealing. The oil-well tubing annealing is made with purpose of repair, especially of light and heavy oil’s deposit removal, corrosion and erosion results removal, which occurs while operating. Gas is used as a fuel. It is fed to the gas burner. Real problem while operating gas facilities is gas leaking, which leads dangerously explosive steam-and-gas mixture formation. The one of the reasons of gas leaking is broken-down safety shut-off valve. If the valve doesn’t shut off natural gas feeding, it may seem that the valve is blocked up. To detect such kind of defect it’s necessary to use the system of valve penetration control. Nowadays such systems are used on the productions, and the main element of such system is a pressure switch device. The main problem of such systems is low accuracy of measurements and low operation safety. In order to provide safety rate for personal, and to exclude gas leaking, to prevent emergency situations and to provide safe operation of the facility, it is offered to use the system of penetration control with analog pressure sensor. The sensor is located between two valves. Pressurized leakage test is carried out in two stages. Depending on test’s results the system gives the alarm of valves malfunction or the permission to flame start-up. The result of such system integration is personal safety improving and equipment reliability improvement.

The essence of any Foundry is its furnace. The operation of the furnace legally involves the process of melting metal by hand is highly dependent on human performance as well ability. With increasing demand and improved technology, this is a common approach it is quickly replaced by temperature-controlled libraries. Basic the effectiveness of such a control to compare the temperature of the metal with the set melting temperature and send the corresponding output to the heat or heat feature. The type of temperature and the furnace customize the type of controller used. While such a control system exists, other safety and fuel management controls plans are the essentials of a modern day oven. This paper is intended in the construction of such a gas burner control system. Gas exploded Furnace Control System includes an active Burner Management System a large part of the melting process. The Control system is built with emphasis on Flame Feedback method, which was analyzed in detail. The control system is actually a temperature control system which includes sensor inputs including thermocouple and flame rod, and effects such as large gas valve, heat rod and blower fan motor. Thus this system is aimed at proper burner management that facilitates the furnace operation and ensures safety of not only the furnace-burner system but the plant in general.

This paper presents the thermal and energy analysis of a Solar-LP gas hybrid drying plant built in Zacatecas, Mexico. It is focused on the dehydration of agricultural products. The drying system is a forced convection hot air type with a drying chamber. For the air heating required in the drying process, there are two solar thermal systems: a direct air heating system (48 solar air heaters with an area of 111.1 m2) and an indirect air heating system (40 solar water collectors with an area of 92.4 m2 and 6000 L of thermal storage). Also, there is a backup system of conventional energy (LP gas burner). Two hybrid tests were carried out to dry Nopal (Opuntia ficus-indica) initially operating with the direct system, after that with the indirect system and complementing the energy demand of drying with the conventional system. The effective drying time was 14.3 and 11.7 h, removing a total of 179 and 183 kg of water, respectively. The air temperature at the entrance of the drying chamber was around 59 °C. The solar fraction obtained for this hybrid mode of operation was around 80%. The thermal analysis of the direct and indirect air heating system, together with the conventional system, are presented and discussed. The performance of the solar systems is finally compared with a conventional LP gas drying system via a cost and return on investment analysis.

The applications of AC unit for heating purposes increase with the improvements in air conditioners’ (AC) automation, performance, and production lines. Besides the developments in technology, heating applications of AC units can be a sustainable and effective solution with the aim of reducing CO2 emissions. In this study, heating costs of a simple dwelling were calculated. Three cities that represent three different climates in Turkey were chosen. Unlike steady-state equations to determine heating loads, transient heat conduction in wall and window components were solved by applying the finite difference method. Temperature deviation in wall and window materials among to thickness direction was calculated. Thus more accurate heating loads were obtained. In order to get realistic results, actual energy prices were used in cost calculations. Heating costs of AC unit that electricity is the only expense were compared with a natural gas burner. It is found that the AC unit is more economical than a gas burner in warm climate region because COP values of AC unit are the parameter that determines the electricity cost. COP in warm climate locations is much higher than that of cold climate region. In regards to heating costs, outside temperature and wind speed characteristics of a place where a building will be constructed should be well-known in order to choose the proper heating system.

Syngas from biomass residues is an alternative fuel to address the ever-increasing fossil fuel supply problem and the issue of releasing toxic gases from the fossil fuel burning process. Syngas is also a renewable fuel and features environmentally friendly fuel. This study was conducted to investigate the performance of the syngas produced from oil palm shells (PKS) using fluidized bed gasifier. In this study, the produced syngas was tested for its combustion performance from the aspect of gas combustion temperature and resulting emission concentrations such as nitrogen oxide (NOx), carbon monoxide (CO) and sulfur dioxide (SO2). The resulting syngas was studied at different ratio of air velocities to fuels. From the test, the ratio of velocity of air to fuel affects the gas combustion temperature and emission emission concentration. By increasing the air velocity to fuel ratio during the gasification process produces more positive effects primarily in improving the temperature of the gas burner combustion and reducing carbon monoxide (CO) emissions. However, the concentration of sulfur dioxide release (SO2) and nitrogen oxide (NOx) increase.

In this article the authors present theoretical and experimental studies of gas-burning devices with the chordal feed of gas jets. The optimum diameter of the nozzles providing for the necessary range of gas jets for a high-quality mixing of fuel gas and air in the mixing chamber of minimum length is determined by calculation. The analysis of the parameters of the flame indirectly proves the reliability of the calculated data. The chordal flow of the gas jets and optimization of their range will significantly reduce the overall structural dimensions of the gas burner units. Short-flame gas-burning devices formed the basis for the creation of the Autonomous heat gun intended for repair and maintenance of engineering networks. Obtaining of a good heat gun is ensured by the motor fan capable of generating a high-pressure jet without connection to an external electrical network. Using of the autonomous heat gun in the housing and communal services is very promising in comparison with similar devices.

Currently, one of the urgent problems of modern gas industry is an energy–saving and energy–efficient use of energy resources. One solution to these problems is to reduce the cost of production of thermal energy, by increasing the coefficient of performance (efficiency) of the boiler equipment. This can be achieved by using modern gas-burning devices – gas burner.Gas burner – a device that supplies the required amount of mixture gas and an oxidizer (oxygen or air), creates the conditions for their mixing, transports the resulting mixture to the point of combustion and provides efficient gas combustion. In this gas-burning device must pass all state tests must be made on a specialized company and meet all modern standards and requirements. There are gas burners in which the combustion is supplied to the place and the gas and the air or gas only. With that, in the first case, when supplied with gas and air, the inside of the premixing gas burner does not occur. One of the factors responsible for the efficient operation of the gas burner is the lack of breakthrough phenomena and flame lift. The method of burning gaseous fuels is determined by the construction of gas-burning device and the degree of efficiency and lack of chemical incomplete combustion will depend on its fulfillment. Most gas–burning devices have common design elements, regardless of their type, such as a nozzle, mixer, burner nozzle, combustion stabilizer. It gives an opportunity for more in-depth study of a particular device gas–burning devices, as well as for the further development and improvement of the parameters of its work.

The KB 5 high pressure gas burners are popularly and widely used at the food stands in Thailand. The gas burner models are of various properties depending on the each factory’s design. The differences of the designs affect the Liquid Petroleum Gas (LPG) consumption to a different extent. This study aimed to evaluate the parameters: the degrees of outer and inner ports; and the number of outer and inner ports of high pressure gas burners which are sold in Thailand. The thermal efficiency was tested with reference to the Standard Industrial stoves in household with liquid petroleum gas (TIS 2312-2549). The result showed that, by increasing the degrees of outer ports from 45 to 80, the thermal efficiency increased by 0.24%; while by increasing the degrees of inner ports from 50 to 60, the thermal efficiency increased 0.11%. By increasing the number of the outer ports from 35 to 38, the thermal efficiency increased 0.44%; while by increasing the number of inner ports from 9 to 15, the thermal efficiency increased by 0.22%. The development of high pressure gas burners should focus on adjusting the degrees and number of inner and outer ports for the overall improvement of the thermal efficiency.

Four scaled (1:5) fire experiments with two identically classified types of commercially available sandwich panels incorporating either stone wool (SW) or polyisocyanurate (PIR) foam as cores were conducted using a modified version of the ISO 13784-1 (Reaction to fire tests for sandwich panel building systems — Part 1: Small room test) standard. This was to assess the suitability of scaled experiments for assessing sandwich panel fire behavior. In the modified version of the test standard (scaled and full experiments), the fire severity was increased to simulate fires that could occur in commercial premises. This was achieved by prolonging and doubling the heat release rate output of the gas burner at the end of the experiments. Furthermore, non-structural damages such as screw-hole damages were applied to the enclosures to reflect real life observations.The results showed differences in the fire behavior, depending on whether the enclosures were constructed of panels filled with SW or PIR insulation material. The mass losses of the insulation materials showed significant contribution from the PIR cores, regardless of fire load and the non-structural damage.The qualitative behavior with respect to the “flashover” failure criterion, as stated in the ISO 13784-1, was successfully obtained in all of the scaled experiments. As such, the scaled experiments mimicked the behavior of the full scale SW experiments to a satisfactory degree. However, the PIR compartments failed considerably earlier in the full scale tests than in the scaled experiments. Therefore, it can be concluded that when the energy contribution from the core material remained negligible compared to the gas burner, the measured parameters matched quite well. Therefore, if the insulating core material does not dominate the fire dynamics of the compartment and the energy from the gas burner dictates the fire scenario then the scaled set-up will predict the temperature in the full scale compartment. Based on this and with further development with respect to, especially, time, this kind of scaled experiments could be a valuable testing method for assessment of the behavior of sandwich panel, and therefore merit further studies and eventually increased use.

We propose a modified classifier that is based on the maximum a posteriori probability principle that is applied to images having the matrix normal distributions. These distributions have a special covariance structure, which is interpretable and easier to estimate than general covariance matrices. The modification is applicable when the estimated covariance matrices are still not well-conditioned. The proposed classifier is tested on synthetic images and on images of gas burner flames. The results of comparisons with other classifiers are also provided.

The impact of the reflection of fire-induced heat from a gas burner was studied experimentally to gain knowledge on the interaction between photovoltaic (PV) panels and a fire. The heat flux was measured in a total of eight points at the same level as the top of the gas burner. The gas burner was placed underneath the centre of a PV panel and the eight points were measured in symmetrical pairs of two at four different distances from the burner. The heat release rate from the gas burner was increased stepwise every four minutes. The measurements were made underneath a PV panel installed in a geometry similar to a commercial East-West orientated mounting system and was compared to a baseline test without the re-reflection from the PV panel. A significant increase of the received heat flux was noticed and the trend indicated an ascending percentage-wise difference as a function of an increased heat release rate. Contrary to the basic view factor theory, the received heat flux was higher underneath the most elevated part of the PV panel, and this occurred due to two important flame related reasons: 1) the deflection of the flame towards the most elevated part of the panel, resulting in an increased amount of radiation from the flame towards the surface; 2) A non-homogeneous distribution of the temperature on the PV panel surface, due to the deflected flame, and thereby a non-homogeneous emission from the heated PV panel. Finally, it was seen that two similar tests conducted with respectively a brand new PV panel and a PV panel tested for the fourth time, showed very comparable results, except during the period when the thin combustible film underneath the new PV panel was burning. This resulted in a higher heat flux during that period and implies that the results presented herein are conservative in that they are lower than what can be expected in case of a real fire hazard, where the PV panel is by definition involved in the fire for the first time. It can be concluded that PV panels can have a significant contribution in roof fires, as they stimulate fire spread over the roof on which they have been mounted. These findings emphasise that the risk related to the installation of PV panels is not only associated with the increased fire load and possibility of ignition, but largely also with the changed fire dynamic surroundings of the roof construction.

The characteristics of the combustion temperature, flow velocity, CO distribution and NOx emissions of a 10 MW gas burner at different primary to secondary air ratios are numerically studied using computational fluid dynamics software Fluent. The results indicate that the primary to secondary air ratio in gas burner determines the combustion quality through influencing some parameters directly, such as the combustion efficiency, combustion intensity, profile and stability of flame as well as emission of NOx. Then two evaluation indexes of combustion quality are summarized after analyzing the flame structure and characteristics of the flow. The detailed results reported in this paper may provide a useful basis for NOx reduction and premixed gas burner design. Finally some proposals are given to choose the optimal primary to secondary air ratio for a gas burner.

The paper presents some results of experimental studies of the co-generation of heat and electric energy in the process of an injection gas burner operation due to thermoelectric effect utilization. It also contains a description of the used laboratory installation and presents experiment methods. The authors prove the possibility to use consumer gas burners for electricity generation.

Part 5: Industrial Management and Other Applications; International audience; In this paper we present a fast and easy method of quality monitoring for processes observed by cameras. A process of combustion in an industrial gas burner is used as an example. It is shown that we can observe only a small randomly chosen part of subsequent camera images. We propose a few, working in parallel manner, quality control charts. These Shewart type charts operate on squared norms of sparse partial image projections. Each chart is used for monitoring only a part of the whole camera image. The charts provide a partial decision about the state of the monitored system. A final decision is the logical product of these partial decisions. A simulation study based on 144 images of a working gas burner is presented.