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International audience; Building is one of the economical sectors where solutions are available to significantly reduce energy consumption and greenhouse gases emissions. Electric heat pumps are one of the solutions favored in Europe. Europe recently adopted a conventional primary energy to electricity ratio which enables to compare electric heat pumps and fossil fuel boilers. This leads to an increased consideration for the evaluation of the seasonal performances of heat pumps. Nowadays, the design and sizing of heat pumps are still based on full load performance in order to fulfill thermal comfort under extreme conditions. However, the HVAC industry is switching to designs based on improved seasonal performance. The objective of this work is to model an air to water reversible heat pump that can re-design its components for seasonal performance improvement. In this context, we will present a system model including detailed sub-models of each component of the system: heat exchangers, compressor, and expansion valve. The model converges with the system thermodynamic equilibrium after simulating each component separately. Results obtained are validated through experimental data per component and for the whole cycle. Modeling requirements for the purpose of simulating seasonal performance improvements are discussed.

In this study, plum slices were dried in a heat pump dryer designed and constructed in Ege University, Izmir, Turkey. Drying experiments were carried out at an air temperature range of 45-55°C. The performance of the dryer along with its main components were evaluated using an exergy analysis method. Exergy destruction and capital cost rates were used for the exergoeconomic analysis, which is based on the quantities exergy, cost, energy, and mass (EXCEM) method. Exergy destruction rates to capital cost values Rex were obtained to vary between 1.668 and 2.063 W/ USD at different drying air temperatures. Ren values were observed to range from 6.258 to 5.749 W/USD. Ren values decreased as the drying air temperature increased, contrary to Rex values. Ṙex and Ṙen values increased linearly with increasing temperature due to the loss, whereas Ṙen decreased due to the relatively higher energy utilization efficiency of the heat pump. In the compressor, Ṙen and Ṙex values decreased with the increase in the temperature contrary to the other components. Ṙex had the lowest value in the drying duct. However, in the compressor, expansion valve, and heat recovery, Ṙex values were found to be higher and should be improved in these units. © 2010 Taylor & Francis Group, LLC., TÜBİTAK project no. 106M482