Hydrogen is an unusual substance in that its molecule exists in two forms, known as ortho and para, with markedly different properties. Energy level of the ortho molecule is higher than para, therefore, the latter is employed for industrial purposes. Consequently, for a high  conversion of  ortho to para hydrogen a catalyst reactor must be employed.  Therefore, one of  the main obj...

In this study, the problem of a parallel connected power and absorption cooling cogeneration system was analyzed and then an improved configuration based on this system was proposed. This system can make cascade utilization of the turbine exhaust heat. By varying turbine outlet pressure, different turbine exhaust vapor temperatures can be obtained, resulting in different amounts of heat that ca...

The frrst part of this paper presents carbon dioxide air conditioning units which were installed in two city buses. The two buses were tested "on-the-road" during summer 1997 in Bad Hersfeld, Germany. By the end of 1997, the air condition systems of the two buses had been running together for more than 860 hours proving that C02 systems fulfill important on-the-road requirements. In the second ...

Refrigeration is one way to maintain the temperature of a material or room at lower level than ambient conditions around it by absorbing heat from room. The refrigeration system that widely used today for industrial purposes use vapor compression cycle, where in this cycle components has an important role compressor. Over time, performance compressor will decrease, so affect absorption process ...

A simple vapor-compression refrigeration system becomes ineffective and inefficient as it consumes a huge energy supply when operating between large temperature differences. Moreover, the recent Kigali amendment has raised concern about phasing out some hydrofluorocarbon refrigerants due to their impact on environment. In this paper, numerical investigation is carried compare performance of cas...