摘要
本文对制冷工况下,单级跨临界二氧化碳（CO_2）带膨胀机循环、跨临界CO_2双级压缩无回热器循环、跨临界CO_2双级压缩加回热器循环、跨临界CO_2双级压缩一级节流无回热器循环和跨临界CO_2双级压缩一级节流加回热器循环五种循环的性能进行了分析比较。结果表明：当膨胀机的效率为60%时,在所规定的蒸发温度范围内（-10～20℃）,单级跨临界CO_2带膨胀机循环的性能要高于其它四种双级压缩循环。当蒸发温度为5℃时,只要膨胀机的效率大于32%,单级压缩膨胀机循环的性能就高于其它四种双级压缩循环。对于四种双级压缩循环,前两种循环适用于中高温制冷,且回热循环性能较好;后两种带中间冷却器的循环适宜于中低温制冷,增加回热器后性能反而下降。
The performances of single-stage transcritical CO_2 cycle with expander,transcritical CO_2two-stage cycle without intermediate heat exchanger,transcritical CO_2two-stage cycle with intermediate heat exchanger,transcritical CO_2two-stage primary throttling cycle without intermediate heat exchanger and transcritical CO_2two-stage primary throttling cycle with intermediate heat exchanger are analyzed in refrigeration condition. The results show that the single-stage expander cycle outperforms the other options when the expander efficiency is 60% at the given evaporation temperature（- 10 ℃ ～ 20 ℃）. When the evaporation temperature is 5 ℃ and the expander efficiency is greater than 32%,the performance of expander cycle is the best. In the other four two-stage cycles,transcritical CO_2two-stage cycle without intermediate heat exchanger and transcritical CO_2two-stage cycle with intermediate heat exchanger are reasonable options in medium and high evaporation temperature,and the performance of using internal heat exchanger in cycle is much better; transcritical CO_2two-stage primary throttling cycle without intermediate heat exchanger and transcritical CO_2two-stage primary throttling cycle with intermediate heat exchanger are more applicable to medium and low evaporation temperature. And the using of internal heat exchanger decreases the cycle performance.
出处
《制冷学报》
CAS
CSCD
北大核心
2016年第3期53-59,共7页
Journal of Refrigeration
关键词
膨胀机
CO2
跨临界循环
双级
单级
expender
carbon dioxide
transcritical cycle
two-stage
single-stage
