Efek Bentonit pada Karakteristik Pembakaran Droplet Biodiesel Kelapa Sawit

The blends of fuel to base liquid fuels for the enhancement of combustion properties has long generated interest since it is linked to improvement in combustion properties in biodiesel fuels. This work investigates the effect of bentonite nanoparticles on the combustion characteristics of palm oil biodiesel. These nanoparticles are added in various compositions on biodiesel which are 0% (B0), 10% (B10), 20% (B20) and 30% (B30). The insulin pen was used to make Sub-millimeter-sized spherical droplets, and the combustion process of droplets was recorded using a camera in atmosphere condition. The fuel was dripped on the tip of the thermocouple junction and ignited using a torch of the butane-air mixture on a cylindrical burner. Properties such as ignition delay, burning rate, and flame temperature of droplets were measured with post-processing of the resulting images. The results showed a decrease in ignition delay and an increase of flame temperature with the increase of bentonite percentage due to bentonite acts as a catalyst capable of accelerating the reaction rate. However, the burning rate decrease with the increasing of bentonite percentage due to the oxygen content of the mixture is getting lower.

Numerical Study of Combustion Regimes and Heat Radiation of Cylindrical Porous Burner

Temperature and radiative characteristics of different regimes of premixed gas combustion in porous cylindrical burner are investigated numerically. Two-temperature thermal diffusion model with radiative heat transfer and external radiative heat losses described in the framework of Eddington model is applied. It is found that two different combustion regimes can be realized under the same mixture equivalence ratio and flow rate depends on ignition conditions. It is shown that total radiative heat flux from the external surface of the burner and burner’s radiative efficiency strongly depend on the combustion regime.

Numerical Study of the Heat Radiation from the Porous Cylindrical Burner with Radiative Heat Exchange

The problem of premixed gas combustion in porous cylindrical burner is investigated numerically. Two-temperature diffusional-thermal model taking into account radiative heat transfer described in the framework of Eddington model is applied. It was found that radiative heat transfer affects the characteristics of filtration combustion, such as temperature distribution and the flame radius, substantially. It is demonstrated that the overall heat flux from outer burner surface is significantly caused by heat radiation from the inner regions of the porous media. Account of the thermal radiation from the burner interior leads to the shift of the spectral power distribution maximum towards the short wave region in comparison with spectral density calculated on the base of burner outlet surface temperature.