In this study, a novel dual-nozzle ejector enhanced vapor-compression cycle (DEVC) for solar assisted airsource heat pump systems is proposed. In DEVC, the use of the dual-nozzle ejector for recovering the expansion losses is a very promising approach to improve the cycle performance. A mathematical model of the DEVC is developed to predict its performance under specified operating conditions. ...

Aim of this project is the development of a new heat pump system with economizing that is able to improve the heating performance using two or more heat sources at different temperature levels. These heat sources are incorporated into the system with minimal loss of exergy by adding the heat at different pressure levels. Practical applications for such systems are for example buildings with a h...

A hybrid heat pump cycle of the heat amplifier type integrating a booster compressor between the generator and the condenser for distributed heating is simulated and analyzed. The interrelation between the two sub-cycles and the hybridization principle are explored. The theoretical analysis is demonstrated by a H2O/LiBr based hybrid cycle simulation. Investigation of the interaction mechanisms ...

This paper presents recent developments and state of the art for transcritical CO2 cycle technology in various refrigeration, air-conditioning and heat pump applications. The focus will be on fundamental process and system design issues, including discussions of properties and characteristics of CO2, cycle fundamentals, methods of high-side pressure control, thermodynamic losses, cycle modifica...

Combination chemotherapy is often used to treat cancer. Many studies have shown schedule-dependent effects between anticancer drugs. Our previous studies showed that K-562 cells pretreated with non-cytotoxic concentrations of 4-hydroperoxycyclophosphamide (4-HPC), which is a preactivated analog of cyclophosphamide (CY), enhanced the cytotoxicity of etoposide (VP-16). The appearance of cellular ...

The performance of the two types of vapor-injection (VI) cycles in a heat pump system is compared. The vaporinjection cycle using an internal heat exchanger (IHX) has a choice to select the branching point of the injection stream. The two VI cycles are different in terms of branching points of the injection stream. Different branching points of the injection stream influence the heating capacit...

Carbon dioxide is a safe, economic and environmentally sustainable refrigerantwhich can be used in heat pump and refrigeration systems. Research into the performance and benefits of a transcritical heat pump cycle using carbon dioxide began in the early 1990s. Theoretical and experimental research, as well as commercial system development, has improved transcritical system performance to a leve...