Table 2 Comparison of the THP for different turbulator designs.

1

Trapezoidal winglet and wavy groove⁴⁴

2.76

\(Re: 4780\) 45° angle of attack

2

Perforated winglet³⁴

2.01–1.78

\(Re: 4100-25500\)

\(d=5 \text{mm}\)

30° angle of attack

3

V down baffle blocks with racetrack-shaped holes²⁶

1.43

\(Re: 13000\)

\(D=53.65 \text{mm}\)

4

Conical Protrusion Ribs²⁷

1.346

\(Re: 4000\)

\(e/D=0.044\),\(p/e=10\)

5

Tetrahedron-shaped turbulators [Present study]

1.78–1.61

\(Re: 9000 - 24000\)

\(e/D=0.27\), \(P/D=0.812\) \(p/D=0.75\),\(\beta =-30^\circ\)