Submitted in Partial fulfillment of the requirement for the degree of Master of Science Abstract: Particle-laden flow is described as the flow with suspended particles in a fluid and is ubiquitous in nature. This type of two-phase flow is known to have various applications ranging from nature to industrial sectors. In the industrial sectors, particle-laden flow as a method to enhance heat transfer, particularly in heat exchangers, has long been a field of interest amongst researchers. With the increasing number of studies conducted in this field, deeper understanding on the characteristics of this flow in a duct is of importance. In the present study, an open source software, OpenFOAM, is used to model particle-laden laminar flow under Eulerian and Lagrangian frame for three different tube shapes - square, circular and equilateral triangle, so as to investigate its flow characteristic. Laminar water droplets-air flows in the entrance region of the ducts with Reynolds number 200 and Stokes number 1.88 are compared for each cross section of diameter 0.05m. Similar patterns are observed for velocity changes in laminar flows of the three ducts, in that the maximum velocity is found to be at the center of the duct towards the duct outlet. Adding water droplets into the airflow are also found to have slower down the velocity of the airflow in the entrance region of the duct.