Comparing among second, third, and fourth generations (genetically modified) of biodiesel feedstocks from the perspective of engine, exhaust gasses and fatty acid: Comparative assessment

Abstract

Three new types of biodiesel are examined in this report, including the second, third, and fourth generations. Various factors (oxygen to carbon (O/C), hydrogen to carbon (H/C), carbon-chain lengths (CCLs), saturated and unsaturated fatty acids) have been investigated on engine performance, exhaust gasses, and combustion. Three new types of oil, second (Taxus baccata), third (algae Ulothrix) generation), and fourth (Mentha pulegium) generation (genetically modified) were implemented. The effect of CCLs on viscosity and heating values (HV) proved the promotion of CCLs enhances HV and viscosity; the third generation obtained the highest torque and power compared to the other two generations. Results demonstrated that the advance of the viscosity and diminish of the HV triggers the increase of BSFC and the lowest BSFC presented by the third generation. Regarding outcomes, the rise of unsaturation acids and reduction of CCLs can decline the CN, so the maximum EGT presented by the fourth generation of biodiesel is in contrast with the third generation. The extended CCLs and the lowermost O/C influenced CO and HC, which third-generation showed a minimum. The influence of fatty acids on CN and NOx was displayed, and the third generation gained the lowest NOx. The fourth generation exhibited excessive soot, and the third generation showed the lowest soot. The third-generation biodiesel had the lowest peak pressure compared to other samples. The fourth generation is still less efficient than the third generation, which can be proved that this generation has better results.