Density and compressibility are primordial parameters for the optimization of diesel engine operation. With this objective, these properties were reported for waste cooking oil biodiesel and its blends (5% and 10% by volume) mixed with diesel. The density measurements were performed over expanded ranges of pressure (0.1 to 140 MPa) and temperature (293.15 to 353.15 K) compatible with engine applications. The isothermal compressibility was estimated within the same experimental range by density differentiation. The Fatty Acid Methyl Esters (FAMEs) profile of the biodiesel was determined using a Gas Chromatography–Mass Spectrometry (GC-MS) technique. The storage stability of the biodiesel was assessed in terms of the reproducibility of the measured properties. The transferability of this biodiesel fuel was discussed on the basis of the standards specifications that support their use in fuel engines. Additionally, this original set of data represents meaningful information to develop new approaches or to evaluate the predictive capability of models previously developed.

The paper presents the effects of blend injection and dual injection strategies on mixture formation and combustion of syngas-biogas-hydrogen fueling engine working in the solar-biomass hybrid renewable energy system. The research was performed by simulation method on a retrofitted Honda GX200 spark-ignition engine. The results show that at the end of the compression process, in the case of blend injection of 50% syngas-50% biogas, the fuel-rich zone was positioned on the top of the combustion chamber, whereas in the case of dual injection, this zone was found on the top of the piston. In the case of 50% syngas-50% hydrogen supplied, at the end of the compression process, the fuel-rich area observed on the top of the piston with slightly deflected towards the inlet port in both cases of blend and dual injection. When shifting from blend injection mode to dual injection mode, in the case of 50% syngas-50% biogas fueling engine, the mean temperature of the exhaust gas decreased from 1208 K to 1161 K and the NOx concentration decreased from 1919 ppm to 1288 ppm. In the case of a 50% syngas-50% hydrogen fueling engine, the mean exhaust gas temperature decreases from 1283 K to 1187 K leading to a decrease in NOx concentration from 3268 ppm to 2231 ppm. The dual injection has the advantage of lower NOx emission, whereas the blend injection has the advantage of higher efficiency