Experimental investigation of an entropy production in a linear blade cascade

Abstract

The vortical structures in turbomachinery are crucial phenomena that significantly impact the machine’s efficiency. Therefore, investigating them is essential for a better understanding of the machine’s operation.The presented paper focuses on an experimental investigation of entropy production in a linear blade cascade composed of prismatic blades for two pitch-to-chord ratios, t/c = 0.6, and 0.9. The effects of the inlet flow angle, α1 = −20°, 5°, 30°, and outlet isentropic Reynolds number, Re2,is = (0.8, 1.2, 2.5, and 4.5) × 105, are examined based on pressure measurements.Entropy production is evaluated as a balance of fluxes through the inlet and outlet boundaries of the control volume. The paper provides a detailed discussion of the local distribution of entropy production and vorticity in the flow field, as well as their evolution with the tested parameters. The correlations between the integral values of entropy production and the tested parameters are also given.