Investigation of Unsteady Pressure Pulsation in New Type Dishwasher Pump with Special Double Tongue Volute

Table 1

Essential parameters of the pump.

Parameter	Value
	Model 1	Model 2	Model 3
Design flow rate, Q (L/min)	55	55	27.5
Impeller speed, n (r/min)	3000	3000	3000
Volute speed, n1 (r/min)	0	60	0
Number of blades, Z	8	8	8
Volute inlet width, b3 (mm)	17.8	17.8	17.8
Volute base circle diameter, b2 (mm)	46	46	46
Volute tongue angle, θ (º)	34	34	34
Impeller inlet diameter, Din (mm)	32	32	32
Impeller hub diameter, Dhub (mm)	14.9	14.9	14.9