Analysis of a novel combined power and ejector-refrigeration cycle

A novel combined power and ejector-refrigeration cycle using zeotropic mixture is proposed. In the combined cycle, the turbine exhaust from the organic Rankine cycle entrains the vapor from the ejector-refrigeration cycle. And the zeotropic mixture is divided into the power cycle and the ejector-refrigeration cycle through a vapor-liquid separator. And these two flows have different composition. The cycle performance with different fluid composition is evaluated and it is compared with a conventional combined cycle. It is found that the cycle exergy achieves a maximum value of 10.29% with mixture isobutane/pentane (40%/60%), and the thermal efficiency gets a maximum value of 10.77% with mixture isobutane/pentane (70%/30%). The temperature glide in the evaporator achieves a maximum value of 15.09 K with mixture isobutane/pentane (80%/20%). The parametric analysis shows that the cycle performs better in lower condenser temperature. Though the refrigeration cycle achieves lower evaporating temperature in higher generating temperature, the power output is reduced.