Research on Multiobjective Optimization of Bulb Tubular Turbine Based on Orthogonal Test

Table 1

Orthogonal test plan.

Test plan	Experimental factors
	Number of guide vanes Z0 (A)	Distance between guide vane and blade L1 (B)/mm	Hub ratio d (C)	Relative twist angle of blade △β0 (D)/°	Cascade solidity l/t (E)
1	14	1710	0.29	20	0.72
2	14	1852.5	0.31	23.5	0.76
3	14	1995	0.33	27	0.80
4	14	2137.5	0.35	30.5	0.84
5	16	1710	0.31	27	0.84
6	16	1852.5	0.29	30.5	0.80
7	16	1995	0.35	20	0.76
8	16	2137.5	0.33	23.5	0.72
9	17	1710	0.33	30.5	0.76
10	17	1852.5	0.35	27	0.72
11	17	1995	0.29	23.5	0.84
12	17	2137.5	0.31	20	0.80
13	20	1710	0.35	23.5	0.80
14	20	1852.5	0.33	20	0.84
15	20	1995	0.31	30.5	0.72
16	20	2137.5	0.29	27	0.76