Abstract
Equations for calculating the flow distribution of the dividing header system which is composed of a dividing flow header and parallel branch pipes, and for one of the combining header system which is composed of a combining flow header and parallel branch pipes are derived respectively.
The flow distribution factor σd and σc given by
σd=ηd/Rm2d, σc=ψn/Rm2c
introduced in those equations are dimensionless numbers which control the flow distributions of the dividing header system and of the combining one respectively, where ηd is the diffuser factor of the dividing flow header, ψn is the nozzle factor of the combining flow header, R is the resistance coefficient of the branch pipes and md, mc are the cross-sectional area factors of the dividing and the combining header systems.
The flow distributions of the header systems calculated from those equations are in good agreement with the experimental results. The factors ηd in σd and ψn in σc characterizing the flow states in the headers are formulated from the analytical models and are evaluated from the experimental data respectively.
Pressure distributions calculated from the data of single branch pipe are not in agreement with pressure distributions measured along the headers.
