Exhaust Heat Recovery System Research Articles

Wärtsilä - Haldor Topsøe SOFC Test System

In this paper, the design and construction of a 1 - 5 kW SOFC test system is presented together with initial test results obtained during the first 1080 hours of operation. The main purpose of the test system is to analyse and demonstrate a complete SOFC system including fuel and air supply systems, heat exchangers, fuel processing units, power electronics etc., as well as be a platform for testing and evaluation of individual BoP components. The study describes basic design criteria and properties of the test system. Characteristics of major sub-systems such as fuel and air supply, steam supply, purge gas, exhaust heat-recovery, power electronics and control system are also explained. The system will be used for system testing and modelling purposes for several years to come. It will also support product development and designing of an upcoming alpha-prototype and other prototype units.

Optimal Operation of a Gas Engine Exhaust Heat Recovery System in Consideration of Temperature Effect on Refrigerator Performance.

The optimal operation of an exhaust heat recovery system in a gas engine cogeneration is investigated in consideration of the influence of chilled and cooling water temperatures on the performance characteristics of exhaust heat and gas fired absorption refrigerators. First, a simulation calculation is carried out to evaluate the performance characteristics of absorption refrigerators. Second, an optimization calculation based on the mixed-integer linear programming is carried out to determine the on/off status of operation and energy flow rates of equipment. In a case study, it is clarified how the strategies for controlling the load of the gas fired absorption refrigerator affect the optimal operation and running cost of the system, and how the optimal operation is advantageous as compared with a conventional one.