THE INFLUENCE OF THE TEMPERATURE OF EVAPORATION AND CONDENSATION ON COLD-PRODUCTIVITY

For reciprocating compressors showed figure 4.10 the influence of the temperature of evaporation and condensation on the refrigerating capacity, as in Fig. 4.13 the effect of these temperatures on electricity demand. Figure 5.9 shows the influence of the temperature of evaporation and condensation on the refrigerating capacity, the boiling point of influence. The power needed for screw compressor appears in Fig. 5.10 show the typical peak on the curve of the set temperature of condensation. These trends screw compressor similar piston compressors, but there are some differences that are worth noting. For both types of compressors of refrigerating capacity is influenced by the volumetric efficiency, the specific volume of the suction pair, and differential pressure. Force influences volumetric efficiency and work of compression.

Because of the screw compressor completes its expulsion of gas almost no amount remaining, there is no gap volume reexpand, as in the case of piston compressors. One would expect that the volumetric efficiency and cooling power drop-off less as differential pressure increases. Table 5.2 shows a comparison of the cooling capacity and power of screw and reciprocating compressors, with boiling point changes. Actually higher condensing temperature 35C (95 F) there is a higher arrival in power of a piston compressor, because the boiling point decreases. But on the low-temperature condensing 20C (68F), F), the percentage reduction in power about the same for the two compressors.

A modest fall in the refrigerating capacity of the screw compressor at temperatures above the temperature of condensation, accompanied by very little reduction in power consumption, as the boiling temperature drops. Unlike piston compressor, rotary screw compressor works more favorably temperature in the drop-down situation. Power piston compressor falls, even if the engine will be able to provide additional power...