Combustion Gas Temperature in Prestressed Concrete Apartment Fires

1971 ◽  
Author(s):  
Joseph John Fedock
Keyword(s):  
Prestressed Concrete ◽  
Gas Temperature ◽  
Combustion Gas

Exposure Test Results of Lu2Si2O7 in Combustion Gas Flow at High Temperature and High Speed

2004 ◽  
Author(s):  
Isao Yuri ◽  
Tohru Hisamatsu ◽  
Shunkichi Ueno ◽  
Tatsuki Ohji
Keyword(s):  
Weight Loss ◽  
Water Vapor ◽  
Partial Pressure ◽  
Gas Flow ◽  
Loss Rate ◽  
Gas Temperature ◽  
Weight Loss Rate ◽  
Combustion Gas ◽  
Vapor Partial Pressure ◽  
Water Vapor Partial Pressure

In order to understand recession behavior and the amount of recession of Lu2Si2O7 in the combustion gas flow, sintered Lu2Si2O7 specimens were manufactured by hot pressing and exposed under various combustion gas flow conditions (T = 1300–1500 °C, P = 0.3 MPa, V = 150 m/s, PH2O = 27–69 kPa, t = 10h). After the exposure tests, etch pits, which are assumed to form due to volatilization of SiO2 in the grain boundary phase, were observed at the surface of specimen. The amount of Lu2SiO5 phase at the surface of specimen increased with the increase of gas temperature or water vapor partial pressure. A corresponding decrease in the amount of Lu2Si2O7 phase was observed. Furthermore, by using the average weight loss rate for exposure times of ten hours, the influence of gas temperature and water vapor partial pressure on weight loss rate was examined, and the amount of recession under gas turbine conditions was calculated.

Mathematical Modeling of Direct Flame Impingement Heat Transfer

2006 ◽  
Author(s):  
German Malikov ◽  
Vladimir Lisienko ◽  
Yuri Malikov ◽  
John Wagner ◽  
Harry Kurek ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Radiation Transfer ◽  
Convective Diffusion ◽  
Heat Fluxes ◽  
Nox Emissions ◽  
Gas Temperature ◽  
Fine Grid ◽  
Combustion Gas ◽  
Calculation Domain ◽  
Diffusion Transfer

Direct flame impingement (DFI) furnaces consist of large arrays of high velocity combusting jets with temperatures up to 1700 K and impinging on complex configuration surfaces of the work pieces. This results in serious convergence problems DFI modeling and computational efforts. A new method of modeling convective-diffusion transfer (CDT) and zone radiation transfer (RT) employing different calculation schemes with a multi-scale grid is presented. Relatively coarse grid calculation domain allows use of conservative and accurate zone radiation transfer method with only modest computational efforts. A fine grid calculation domain is used to predict convective -diffusion transfer for a representative furnace section, containing a small number of jets that allows to significantly decrease the computer time. The main difficulty of coupling between convective-diffusion transfer (CDT) and radiation heat transfer numerical computations is successfully overcome using a relatively simple algorithm. The method allows one to model the physicochemical process taking place in the DFI and reveals as well as explains many features that are difficult to evaluate from experiments. The results were obtained for high velocities (up to 400 m/s) and high firing rates. Maximum (available for natural gas-air firing) total heat fluxes up to 500 kW/m2 and convective heat fluxes of up to 300 kW/m2 were obtained with relatively 'cold' refractory wall temperatures not exceeding 1300 K. The combustion gas temperature range was 1400-1700 K. A simplified analysis for NOx emissions has been developed as post-processing and shows extremely low NOx emissions (under 15 ppm volume) in DFI systems. Good agreement between measurements and calculations has been obtained. The model developed may be regarded as an efficient tool to compute and optimize industrial furnaces designs in limited time.

scholarly journals Test Result of Low NOx Catalytic Combustor for Gas Turbine

1993 ◽  
Author(s):  
Y. Ozawa ◽  
J. Hirano ◽  
M. Sato ◽  
M. Saiga ◽  
S. Watanabe
Keyword(s):  
Natural Gas ◽  
Gas Turbine ◽  
Combustion Method ◽  
Combustion Efficiency ◽  
Gas Temperature ◽  
Gas Turbine Combustor ◽  
Combustion Gas ◽  
Low Nox Combustion ◽  
Catalytic Combustor ◽  
Combustion Tests

Catalytic combustion is an ultra low NOx combustion method, so it is expected that this method will be applied to gas turbine combustor. However, it is difficult to develop catalytic combustor because catalytic reliability at high temperature is still insufficient. To overcome this difficulty, we designed a catalytic combustor in which premixed combustion was combined. By this device, it is possible to obtain combustion gas at a combustion temperature of 1300°C while keeping the catalytic temperature below 1000°C. After performing preliminary tests using LPG, we designed two types of combustors for natural gas with a capacity equivalent to 1 combustor used in a 20MW–class multi–can type gas turbine. Combustion tests were conducted at atmospheric pressure using natural gas. As a result, it was confirmed that a combustor in which catalytic combustor segments were arranged alternately with premixing nozzles could achieve low NOx and high combustion efficiency in the range from 1000°C to 1300°C of the combustor exit gas temperature.

Optimum Operation of Externally-Fired Microturbine in Combined Heat and Power Generation

2007 ◽  
Author(s):  
Juha Kaikko ◽  
Jari L. H. Backman ◽  
Lasse Koskelainen ◽  
Jaakko Larjola
Keyword(s):  
Power Generation ◽  
Heat Exchanger ◽  
Gas Turbines ◽  
Combined Heat And Power ◽  
Small Scale ◽  
Inlet Temperature ◽  
Control Methods ◽  
Gas Temperature ◽  
Combustion Gas ◽  
Part Load

Externally-fired microturbines (EFMT) yield promising performance in small-scale utilization of biofuels. As in larger gas turbines, the part-load performance of the EFMT is very sensitive to the selected power control method, and in general subject to severe degradation at part load. The control parameters typically include the maximum combustion gas temperature or turbine inlet temperature and the speed of the shaft. At the design point, power generation efficiency can be increased by allowing a fraction of air to bypass the burner and the combustion gas – air heat exchanger. At the same time the heat exchanger size is increased. Therefore, the by-pass flow affects the optimal sizing of the EFMT as well. In this paper, the effect of by-pass flow on the part-load performance of a single-shaft EFMT in combined heat and power generation is analyzed. In the application, the microturbine is operated by the heat demand. The control methods incorporate the use of the maximum combustion gas temperature, the speed of the shaft, and the amount of by-pass air. The focus of the study is to determine the economically optimal control scheme for the engine. The economy model uses the profit flow from the EFMT as a criterion. The results show that the inclusion of the by-pass variation in the control methods can improve the economy of temperature-controlled EFMT at part load but has no benefits when using speed control.

scholarly journals PEMODELAN TEMPERATUR DARI PROSES PEMBAKARAN DI REFORMER FURNACE PADA INDUSTRI BAJA

2020 ◽  
Vol 16 (1) ◽  
pp. 25-30
Author(s):  
Trisaksono Bagus Priambodo
Keyword(s):  
Combustion Chamber ◽  
Steel Industry ◽  
Pipe Wall ◽  
Outer Wall ◽  
Conversion Process ◽  
Maximum Temperature ◽  
Gas Temperature ◽  
Combustion Gas ◽  
Process Gas ◽  
Using Data

Conversion processes that involve large amounts of energy include processes in furnace reformers inthe steel industry. The reformer unit used to convert the process gas, namely a mixture of gas andsteam into CO and H2 gas with the help of a nickel catalyst. The heat energy used in the process is theresult of combustion from natural gas using combustion located above the furnace. The most importantthing in the conversion process is the radiative heat transfer in the combustion chamber to the reactionpipe wall so that enough energy is obtained to carry out the conversion process. One way to determinethe heat distribution of the reformer combustion chamber is to know the temperature profile along thereaction pipe, including the pipe wall temperature, the process gas temperature, and the temperatureof the combustion gas used as energy for the process in the reformer furnace. The performanceevaluation of the reformer furnace uses a mathematical model for combustion in the furnace which canlater be developed by knowing the fitting composition of the conversion results. The type of reformerstudied is the top-fired reformer. The results of modeling using data from the steel industry obtained thehighest temperature from the combustion of gas from the burner which is in the reaction pipe at aposition 3-4 meters from the upper end of the reformer around 1300 oC and the temperature of naturalgas-steam in the pipe reaches 860 oC at the end of the pipe. reaction. The pipe wall heating with naturalo ogas fuels provides a maximum temperature ranging from 890 C - 895 C on the outer wall of thereaction pipe, and the pressure inside the reaction pipe ranges from 8.0-8.5 atm.

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