Adequate fluid placement and complete zonal coverage during a matrix acid stimulation is critical to the success of a treatment. The use of distributed temperature sensing (DTS) is a relatively new technique that can be used for monitoring downhole fluid placement during a treatment. It uses a fiber-optic distributed-temperature-monitoring system to provide continuous temperature profiles throughout the entire length of the well, giving relevant information to perform qualitative and, in some cases, quantitative analysis of fluid placement downhole. This paper describes the design and construction of a laboratory scale flow-loop apparatus to demonstrate the application of DTS technology for downhole fluid placement monitoring. The apparatus constructed contains three inlet and exiting points to simulate well perforations, a method to raise or lower fluid temperature and thus introduce temperature spikes or tracers, and optical fiber and sensing equipment and instrumentation to measure and compare measured and calculated rate data. The system is capable of simulating several well flow conditions, such as fluid injection, fluid production and crossflow. The designed apparatus has proven to be versatile, compact, and useful for understanding and training professionals regarding how DTS technology can be used for monitoring downhole fluid flow and placement.