Five responses which were properties of a biodiesel such as a methyl ester quantity (g), kinematic viscosity
value (mm2/s), density (g/L), freezing point of methyl ester (AdegC), and flash point of methyl ester (AdegC), were named y1, y2,y3,y4 and y5 respectively.
Then physical properties of biodiesel composed from cetane number, kinematic viscosity
, kinematic viscosity
, density and higher heating value were calculated in Table 2.
It was also found that Silicone Oil B having kinematic viscosity
of about 10 [mm.sup.2]/s had the best performance among the silicone oil.
Acid value was conducted using ASTM D-298 method, EN 14111 method for iodine value, ASTM D-1298 method for specific mass at 20 [degrees]C, ASTM D-445 method for kinematic viscosity
at 40 [degrees]C and EN 14106 method for free glycerol content.
The kinematic viscosity
was determined by adopting the standard test method ASTM D 445.
As the ship engine is operated with ULSFO, one of the ways aiming at keeping the kinematic viscosity
higher than the minimum is to equip the fuel cooler to keep the fuel temperature below 40[degrees]C.
Although the Ford Cup-type viscometer is a traditional instrument that is easy to handle and for control of the kinematic viscosity
of fluids, it can be considered one of the limitations of this study.
The density and kinematic viscosity
was found to be 0.888 g/mL and 34.1 cSt, respectively.
On examining the correlation coefficients of physicochemical and tribological properties, it is observed that the kinematic viscosity
at 400C has a positive correlation coefficient of 0.83 indicating that density affects viscosity directly.
Due to a very low kinematic viscosity
, in rotation at the minimum speed (18 rpm), the large diesel droplet already spreads over the whole substrate and partially leaves it, thus compromising the calculations of the average area occupied by the liquid and so, of the film thickness.
The flash point, free and total glycerin content, acid number, kinematic viscosity
, and sulfur content were determined by the American Society for Testing and Materials (ASTM) methods (ASTM D6751).