It is common to use multiple mini-hydrocyclones in parallel arrangement for large-scale industrial applications.For two typical parallel arrangements in mini-hydrocyclone group

U-U type and Z-Z type

the characteristics of pressure drop and flow distribution were investigated and compared by using theoretical model and experiments.It is found theoretically that the value of Q3+R2 has great influence on the performance of both parallel arrangements

where Q and R represent the momentum and the friction effects.The performance of U-U arrangement is better if Q3+R2<0

while that of Z-Z arrangement is better if Q3+R2>0.The experimental results show that the Z-Z arrangement presents better pressure drop distribution than the U-U type for 0.05≤P<0.10 MPa

but the flow distribution of both parallel arrangements is non-uniform under the condition.At P=0.10 MPa

uniform pressure drop and flow distribution are found for both arrangements.For 0.10<P≤0.15 MPa

the flow distribution of U-U arrangement is more uniform than Z-Z type.The pressure drop distribution of both arrangements has the same trend and is good.