Influence of Pressure on the Performance of Heat Exchangers in Ammonia-Water Based Power Cycles
Recently the power generation systems using ammonia-water binary mixture as a working fluid have been attracted much attention for efficient conversion of low-temperature waste heat sources to useful energy forms. In this work, ammonia-water based Rankine (AWR) and regenerative Rankine (AWRR) power generation cycles are comparatively analyzed by investigating the effects of turbine inlet pressure on the performances of heat exchangers in AWR and AWRR systems. Temperature distributions of fluid streams in the heat exchanging devices are closely examined at different levels of turbine inlet pressure under the conditions that the minimum temperature difference of hot and cold streams reaches the prescribed pinch point. Results show that the position of pinch point and temperature distributions are sensitively affected by varying turbine inlet pressure, which might be the most important design consideration in the power systems using a binary working fluid.
K. H. Kim and C. H. Han, "Influence of Pressure on the Performance of Heat Exchangers in Ammonia-Water Based Power Cycles", Applied Mechanics and Materials, Vols. 229-231, pp. 1085-1089, 2012