Room: HR N.213
PhD., Mechanical Engineering at University of Twente, Thermal Engineering group, PhD thesis: “Efficiently generated turbulence for an increased flame speed”.
MSc., Mechanical Engineering at University of Twente. Thermal Engineering group, Master thesis: "Synthesis gas production by Pulsed Compression Technology".
Currently involved in:
Up-THERM: Innovative high efficiency phase change fluid based heat engine
In the Up-THERM project a novel heat engine is developed based on a dense working fluid. It is considered as an more simple and cheaper alternative for existing machines in the power range of 1 kW to 1 MW. The working principle of the engine is illustrated and explained in the figure below. An important part of this engine is the regenerator, where during a cycle heat of the working fluid is transferred to a solid matrix and vice versa. By achieving a high level of regeneration the overall efficiency of the Up-THERM engine is increased. A numerical model is created to provide the efficiency as function several geometrical parameters of the regenerator. Experiments are performed to validate this numerical tool which will serve as a design tool for the actual engine that will be constructed.
Figure 1: Schematic view of the thermodynamic cycle of the Up-THERM engine. The engine consists of a cylinder with a differential piston. One part of the piston, i.e., the center part, works as a driving piston which delivers work in the form of hydraulic output. The annular part of the piston serves as a displacer, moving the fluid from the cold displacer part to the hot part and vice versa, via the external heating/cooling circuit. A cycle consists of multiple steps, which are: (upper left) At the start of the cycle the space in the hot part is minimal. Due to the heating, fluid in the hot part expands and pressure rises. (upper right) This forces the piston to move to the right, which displaces more liquid into the hot part. Also work is performed by the driving piston part. (lower left) Once the piston is in the limiting left position the valve openings in the piston allows for the working fluid inside the engine (so inside hot part and cold displacer part) to move into the cold power part. During this pressure equalization step additional work is performed. As soon as the pressure is equal in both compartments, the slightest disturbance will force the piston to the left, such that hot fluid is displaced to the cold side. This fluid will cool down and the pressure decreases and the piston is forced even more to the left. (lower right) The piston moves to the right until it reached the limiting left position, where the valve openings in the piston allow for the pressure to equalize between the two compartments. During this step fluid from the cold power part enters the cold displacer part. Also during this step usefull work can be extracted. Finally, a slight disturbance to the piston will now cause cold fluid to flow through the heating circuit and cause a pressure rise, which in turn forces the piston to the right, such that the cycle repeats itself.