The use of fossil-based fuels in internal combustion engines has become a major challenge and faces with serious transformation regarding emissions. Herein, alternative fuel usage becomes prominent, thanks to a great reduction of these emissions. In this study, using 20% (B20), 50% (B50), and 100% (B100) of waste frying oil biodiesel (WFOB)–diesel blends has been experimentally and theoretically investigated on emission and performance parameters at full load conditions of 1,500–3,000 rpm ranges in the diesel engine. According to the experimental results, it has been shown that torque has not changed significantly, but brake specific fuel consumption enhanced up to 12.98% owing to the lower heating value of biodiesel. In terms of emissions, biodiesel fuels reveal different results. Whereas HC, CO₂, and NO_x slightly increase with B100, all emissions almost reduce with B20, including NO_x and smoke opacity. Maximum reductions of B20 are obtained as 4.51% in CO₂, 29.27% in CO, 39.06% in HC, 6.52% in NO_x, and 25% in smoke opacity emissions. In compliance with theoretical results, usage of biodiesel reduces exergy destruction rate as up to 7.03% and increases exergetic efficiency as up to 5.86% compared to neat diesel except 2,700–3,000 rpm. Consequently, the small addition of waste frying oil biodiesel as 20% is an optimum solution under favor of minimum increase of specific fuel consumption and reduction in all emissions.

在内燃机中使用化石燃料已经成为一项重大挑战，并且面临着排放方面的严峻变革。在此，由于这些排放物的大大减少，替代燃料的使用变得很重要。在这项研究中，已经通过实验和理论研究了使用20％（B20），50％（B50）和100％（B100）的废煎炸生物柴油（WFOB）–柴油混合物的排放和性能参数。柴油发动机的转速范围为1,500–3,000 rpm。根据实验结果表明，扭矩没有明显变化，但由于生物柴油的发​​热量较低，因此制动比油耗提高了12.98％。就排放而言，生物柴油燃料显示出不同的结果。而HC，CO ₂和NO_x随着B100的增加而略有增加，所有排放物几乎随B20的减少而减少，包括NO _x和烟的不透明性。B20的最大减少量为：CO ₂为4.51％，CO为29.27％，HC为39.06％，NO _x为6.52％和烟不透明度排放为25％。与理论结果相符，与纯柴油相比，使用生物柴油的纯柴油除2700–3000 rpm转速外，降低了（7.03％）的火用破坏效率，并提高了高达5.86％的火用效率。因此，在尽量减少比燃料消耗和减少所有排放的前提下，少量添加20％的废煎炸生物油是一种最佳解决方案。