*Performance and Emission Characteristics of Hydrogenation Derived Renewable Diesel… DOI: http://dx.doi.org/10.5772/intechopen.104820*

reported that the best BSFC was achieved at high loads and low engine speed. This is because at low speed, engine friction is reduced and fuel consumption is minimized. When compared with PBD fuel, the application of HDRD resulted in better engine performance in all the engine metrics measured [31]. Also, Ogunkoya et al. [32], Mangus et al. [33], and Kim et al. [34] reported that their respective tested CI engines fueled with HDRD presented lower BSFC when compared with PBD fuel.


↑ *= increased,* ↓ *= decreased, L = liters, C = Cylinder, S = Stroke, DI = Direct injection, NA = Naturally aspirated, AC = air-cooled, WC = water-cooled.*

#### **Table 4.**

*Performance of CI engine fueled with HDRD.*

They attributed the lower BSFC to the lower viscosity and the impact of high heating value which allows for better fuel atomization.

In research, Janarthanam et al. [35] compared the engine performance of HDRD with that of biodiesel in a vertical single-cylinder, four strokes, and 4.3 kW Kirloskar engine across engine loads. They reported that HDRD showed higher BSFC and BTE, particularly at higher engine loads. They attributed these results to the kinematic viscosity and calorific value of HDRD. Similarly, Singh et al. [36], compared the performance of HDRD with biodiesel and PBD blends in a single cylinder, four strokes 3.5 kW direct injection water-cooled test rig at various engine loads. They reported a higher BSFC, BTE, and EGT with HDRD than with biodiesel and PBD blends, as shown in **Figure 6**. According to them, higher calorific value and cetane index of HDRD compared with biodiesel and PBD accounted for these results. Though HDRD has not been widely used in CI engines, a few reported cases show that HDRD is a better alternative to PBD fuel when compared with biodiesel. The properties of HDRD are a major factor propelling the application of HDRD as a viable and effective substitute for PBD fuel.

**Figure 6.** *BTE, BSEC, and EGT of HDRD at various engine loads [36].*

### *Performance and Emission Characteristics of Hydrogenation Derived Renewable Diesel… DOI: http://dx.doi.org/10.5772/intechopen.104820*

Similarly, Preuß et al. [37] tested HDRD and its blends on both light and heavy duty single cylinder CI engines and compared the results with PBD fuel under various operating conditions. The heavy duty research engine was equipped with an AVL 501 single cylinder engine while the light duty research engine had a Ricardo Hydra engine equipped with a Volvo NED4 cylinder head. The authors reported that the use of HDRD in both light and heavy duties engines led to improved BTE and BSFC for all the engine loading conditions. They attributed these results to the high oxygen content and lower heating value of HDRD compared to PBD and their blends. Using HDRD and biodiesel blends in a 4 cylinder 1.9 TDI CI engine text bed, Shepel et al. [38] reported that HDRD generated better BTE and BSFC than biodiesel and its blends. The results are due to the heating value and the specific heat of combustion of HDRD. This result confirms the assertion that HDRD is a better fuel than biodiesel for transportation applications of CI engines.
