Comparative energy and exergy investigations are reported for a transcritical N2O refrigeration cycle with a throttling valve or with an expander when the gas cooler exit temperature varies from 30 to 55 ◦C and the evaporating temperature varies from −40 to 10 ◦C. The system performance is also compared with that of similar cycles using CO2. Results show that the N2O expander cycle exhibits a l...

In this paper the design of annular fin heat exchanger based on economic optimization has been carried out. The optimization process targeted minimizing the lifecycle cost of annular fin heat exchanger that has the same frontal area, effectiveness and heat load of available practical standard geometry exchangers. The lifecycle cost includes both capital and operating costs. Beside the pumping c...

The exergy efficiency depend upon mainly upon the inlet condition of the system because inlet condition best suit for a particular type of the system except to increase the whole system efficiency stresses are done on particular parts of system and research are done on that systems. It was observed that that every part of system has its own and equal importance because ones effect on another wh...

Exergy destruction in adiabatic pipeline flow of surfactant-stabilized oil-in-water emulsions is investigated in five different diameter pipes. The dispersed-phase (oil droplets) concentration of the emulsions is varied from 0% to 55.14% vol. The emulsions are Newtonian in that the viscosity is independent of the shear rate. For a given emulsion and pipe diameter, the exergy destruction rate pe...

Research in the last 15 years has led to die-less incremental forming processes that are close to realization in an industrial setup. Whereas many studies have been carried out with the intention of investigating technical abilities and economic consequences, the ecological impact of incremental sheet forming (ISF) has not been studied so far. Using the concept of exergy analysis, two ISF techn...

This paper introduces the dual-mode refrigeration system for ice storage air conditioning. A computational model relating to the exergy loss amount and loss rate is developed in each component of the refrigeration cycle loop. A case study is presented to demonstrate the applicability of the model developed. Exergy analysis results of the refrigeration system in ice storage operating mode are co...

On the basis of the exergy analysis, a performance optimization is carried out for a generalized irreversible refrigerator model, which takes into account the heat resistance, heat leakage and internal irreversibility losses. A new ecological criterion, named coefficient of performance of exergy (COPE), defined as the dimensionless ratio of the exergy output rate to the exergy loss rate, is pro...

This study presents comparative energy and exergy analyses of a single cylinder, four stroke Ruston diesel engine. The test was conducted by varying the load between zero and maximum while keeping the engine speed constant. Then, using the steady-state data along with energy and exergy balance equations, various performance parameters of the engine were measured. From the study it was found tha...

The current method used for calculating societal aggregated exergy efficiencies is reviewed. Cooling is introduced as an end-use category; conversion efficiencies for heating processes are obtained for each energy carrier; and electricity shares per end-use are retrieved for each sector, improving the accuracy of the estimated values of aggregated exergy efficiencies. We show that: (1) cooling ...