For rack-mounted electronics, flow distribution is desired as per the heat load characteristics. In the literature, attainment of flow uniformity through manifolds is highlighted and widely discussed as it has more applications. To attain desired flow distribution, the complexity of the problem increases. In the present paper, the Design of Experiments (DOE) along with response surface optimization is used to arrive at desired flow, which includes uniform flow also. A three-dimension, 10-channel Z-type manifold is considered for the study. This model is taken from experimentally verified and published data for which desired flow patterns are achieved. Flow requirement through each channel is set as a parameter for optimization and by the defined sample set under DOE, uniform flow and pattern flow are achieved by introducing suitable orifices. Multi-Objective Genetic Algorithm (MOGA) is used for obtaining orifice diameters. A good agreement is observed between the attained flow patterns and desired patterns. This approach is simple and can be implemented for industrial applications.