Throughout the last 40 years, efficient mixing of exhaust streams in mixed turbofan cycles has received much attention in the research community. Reductions in specific fuel consumption, jet noise, and heat signature and in the case of ejectors, increases in static thrust are all possible benefits when a properly designed mixing device is used. Previous research has shown that corrugating the trailing edge of the adjacent splitter plate can promote rapid mixing. Current research seeks to understand scallops when integrated into the lobed surfaces and their roll in the mixing process through the use of simultaneous Particle Image Velocimetry (PIV) and Planar Laser Induced Fluorescence (PLIF) whole field measuring techniques.
The goal of these experiments is to obtain the air velocity and temperature in a simplified engine compartment at full thermal ‘soak’ condition. This occurs after the vehicle endures high thermal loads due to performing a sequence of operating conditions such as highway driving and trailer grade loads in hot ambient environment (> 38 º C). The vehicle is then parked in a windbreak, and power is shut down. Due to the absence of any under-hood airflow from the fans or the ambient surroundings, the under-hood begins a thermal process that is dominated by buoyancy driven flow. During this soak process the temperature can rise higher in a tightly packed under-hood.
The simplified geometry consists of a glass engine compartment, trapezoidal shaped aluminum engine block and two exhaust pipes. This geometry allows for simpler computational modeling and experimental testing while retaining the general shape and main components of an engine compartment. It is interesting to note that the geometry used in the present study is a combination of several classic buoyancy driven flow experiments. They include the heated inclined surface, heated horizontal cylinder and heated horizontal surfaces.
Velocity measurements are conducted using PIV with a specially developed particle seeding system. Temperature measurements are conducted with thermocouples.
The main objective of these measurements is to understand the interaction between the biopsy tissues and the fixative liquids for different cassette designs. These studies will result in understanding of the fluid dynamics of the tissue processor and the biopsy cassettes. The result of this research is being used to improve the design of a new generation of processors for more efficient processing of biopsy tissues.