Table 4: The empirical constants for by (11) reported in the literature and in the current study.

ReferenceLiquid systemConstant χConstant λConstant ωType of impeller Average relative error (%)Valid for (kW/m3)

[21]Water0.250.75Flat blade turbineNANANA
[22]Na2SO40.4903 0.5788Rushton turbineNA9.3NA
[23]Tap water0.478 0.4910Disc turbine-pitched blade0.98NANA
[23]Tap water0.4244 0.6904Rushton turbine0.98NANA

Current studyXanthan gum solution with 0% palm oil fraction0.00800.23850.2180Rushton turbine0.7414.470.141–1.11
Xanthan gum solution with 5% palm oil fraction0.00610.35010.1435Rushton turbine0.9012.150.094–0.89
Xanthan gum solution with 10% palm oil fraction0.00650.35280.1626Rushton turbine0.9310.870.079–0.89
Xanthan gum solution with 15% palm oil fraction0.01610.25070.0773Rushton turbine0.983.270.058–0.83
Xanthan gum solution with 20% palm oil fraction0.01190.25580.1395Rushton turbine0.965.990.039–0.72
Xanthan gum solution with 50% palm oil fraction0.01780.18900.1690Rushton turbine0.8412.060.031–0.64