Contained System (Summary Of Thermodynamics)

WARNING: This page is about a different car, the 2002 Volvo C70, 2001 Volvo C70, 2000 Volvo C70, 1999 Volvo C70, and 1998 Volvo C70. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Identifying Contained System (Summary Of Thermodynamics)

Courtesy of VOLVO CARS OF NORTH AMERICA.

If two beakers, a compressor and a choke valve are connected together as illustrated, it is a contained system.

The compressor and the choke valve divide the system in to a low pressure section and a high pressure section.

Without the choke valve the compressor would only function as a pump.

Function

The choke valve governs the quantity of liquid that is released up to the right beaker. The quantity of liquid must be so much that the final remains of the liquid evaporate precisely before the beaker spout. Too little or too much liquid means that the amount of heat that can be taken up reduces.

The compressor lowers the pressure and the temperature in the right beaker. The liquid in the beaker then boils and evaporates at low temperature. This results in the temperature difference between the flame and the liquid becoming greater and the heat transfer from the flame to the liquid becomes quicker and more efficient.

The compressor extracts the gas from the right beaker, increases the pressure of the gas and temperature and presses out the gas in the left beaker. As a result the temperature difference between the gas and the ambient temperature becomes great. The gas then condenses at a high temperature and the heat transfer from the gas to the air becomes rapid and efficient.