China
Africa
Explore chapters and articles related to this topic
Microturbines and Cogeneration
Published in Bernard F. Kolanowski, Small-scale Cogeneration Handbook, 2021
A combustion chamber mixes fuel and compressed air to provide the combustion gases that enter the turbine wheel at high temperatures. These gases expand through the turbine wheel which provides the power to spin both the compressor and generator which is attached to the same shaft as the turbine wheel. See Figure 16-1.
Power unit – engine
Published in Andrew Livesey, Motorcycle Engineering, 2021
To improve thermal efficiency, two factors of combustion chamber design should be considered: swirl ratio and surface-to-volume ratio. The formulas are quite self-explanatory: Swirl Ratio=air rotation speed/crankshaft speed
Optimization of a Cement Plant Preheating Tower, Equipped with a Precalciner, Burning Pulverized Coal
Published in Maria da Graça Carvalho, Woodrow A. Fiveland, F. C. Lockwood, Christos Papadopoulos, Combustion Technologies for a Clean Environment, 2021
C. Belot, D. Goffe, D. Grouset, C. Bertrand, B. Homassel, J. L. Philippe
One can see that there are some difficulties in obtaining complete combustion inside the combustion chamber. This is based on the following observations: in the first set of data one remarks on a high level of CO at the bottom of the furnace, and in both sets of data the temperature in the lower part remains high, sometimes higher than in the upper part, indicating that the combustion is still progressing after the outlet of the precalciner. Due to residence time effects, this is amplified when the production level is raised. When more fuel is used, one can see that the level of unburnt gases rises at the precalciner outlet.
A Combined Experimental and Computational Study of Soot Formation in Normal and Microgravity Conditions
Published in Combustion Science and Technology, 2022
Richard R. Dobbins, Jesse Tinjero, Joseph Squeo, Xinyu Zhao, Robert J. Hall, Meredith B. Colket, Marshall B. Long, Mitchell D. Smooke
The most commonly implemented combustion chambers for practical applications are gas turbines, furnaces, and internal combustion engines. While premixed or partially premixed flames may be appropriate for certain small-scale or household applications, the vast majority of large-scale industrial combustion applications require the non-premixed (diffusion) flame configuration, as safety and stability is increased by maintaining the fuel and oxidizer separate. Even if partial premixing of fuel and oxidizer is implemented, a diffusive component will remain in the combustion process. Thus, understanding diffusion flames is of fundamental importance to optimizing combustion processes, minimizing emissions, and ensuring the safe combustion of fuels. As the local stoichiometry in a diffusion flame varies from pure fuel to pure oxidizer, the propensity to form soot exists in the richest parts of the flame. After the fuel is pyrolyzed, soot precursors form, and these nucleate and grow into soot particles. While the soot can potentially be oxidized as it passes into the oxidizer, there are also conditions where soot particles pass through the flame unconsumed.
Influence of carbon nanotubes as additive in diesel-biodiesel blends in CI engine - an experimental investigation
Published in International Journal of Sustainable Engineering, 2021
The unburned HC emission from the exhaust is the effect of incomplete combustion of fuel inside the combustion chamber. Figure 13 shows the emission of hydrocarbon vs. load for the various fuel blends. Absence of adequate air in combustion chamber results in incomplete combustion. The CNTs have improved the fuel-air mixture during the fuel injection, and hence this nanoparticle propagation results in full combustion in the cylinder which leads to a reduction of HC emission at the exhaust. This is because of higher surface area to volume ratio which boosts the mixing of fuel and air in combustion process which has enhanced the ignition characteristics of nanoparticles. The maximum reduction of HC emission is for B15C100 as seen from Figure 13. This happened due to higher content of oxygen present in the biodiesel which facilitates the more complete combustion (Sahoo et al. 2007). The hydrocarbon emission was found to be noticeably reduced about an average of 11.32% by addition of CNTs with fuel blends for higher loads. The main reason is intensive atomisation and a significant supply of fuel in existence of nanoparticles in cylinder which results in oxidation of CO and HC during the combustion process (Sadhik Basha and Anand 2014). The results obtained for HC emission in this experiment were similar to the previous researches (Perumal and Ilangkumaran 2018).
A review of bio-fuelled LHR engines
Published in International Journal of Ambient Energy, 2020
Krishna Kumar Pandey, S. Murugan
Internal combustion (IC) engines are considered as the most promising energy conversion devices because they deliver mechanical power in a wider range from kilowatt to megawatt. They are used in transportation, power, agriculture, domestic and commercial sectors (Abbas and Elayaperumal 2019; Parlak, Yasar, and Eldogan 2005). They are inevitable devices in places where renewable energy sources such as solar, wind, tidal cannot be used for a stand by the supply of power. Although the integration of multiple renewable energy systems is possible for obtaining mechanical power, complete obsoletion of the IC engine may not be possible. In a combustion chamber, when combustion occurs, the fuel’s chemical energy is first converted into heat energy or low-grade energy and then converted into mechanical energy or useful work. Due to unavoidable heat loss, the maximum thermal efficiency of the IC engine is about 35–45%. In the IC engine, heat loss arises from different sources that include heat loss (Rakopoulos and Mavropoulos 1998; Taymaz 2006) (i) through exhaust gas (ii) cooling water and (iii) other unaccounted losses.