Indirect combustion technology with renewable non-edible transesterified oil feedstock

This investigation focused on the combustion and performance of an indirect injection (IDI) diesel engine powered by a non-edible biodiesel blend, Brassica Carinata. This oilseed has become an attractive non-edible feedstock for biodiesel in the United States, given potential agronomical advantages. A small bore, single cylinder IDI engine was run at 2000 rpm and 5.5 bar indicated mean effective pressure (IMEP) using ultra-low sulfur diesel #2 (ULSD#2) and compared with C50, a 50% Carinata biodiesel-ULSD#2 blend (by mass). The apparent heat release for C50 reached a maximum of 22.04 J/deg which was 6.3 % lower and peaked 1.80 CAD before ULSD#2. The radiation and convection heat fluxes had similar maximum values of 0.62 MW/m² and 1.34 MW/m², respectively. The brake specific fuel consumption (BSFC) of C50 was 211.05 g/kWh, which was 9% higher than for ULSD#2. The mechanical efficiency was maintained relatively constant at 55% while the indicated thermal efficiency of the engine reached 59%. Both fuels produced similar nitrogen oxide (NOx) emissions with ULSD#2 and C50 producing 2.29 g/kWh and 2.23 g/kWh, respectively. The results indicate that the IDI engine can optimally work with concentrations up to 50% biodiesel.