一、對流熱傳優(yōu)于傳導熱傳
動態(tài)蓄冰槽是基于對流熱傳優(yōu)于傳導熱傳原理，將盤管間以隔板隔成數(shù)空間室，再配以一小型循環(huán)水泵將水導流而上下循環(huán)于各隔板間室，或利用泵將蓄冰槽內(nèi)水從底部抽出，從頂部撒水，如此可以利用最小的動力泵（每槽約1～2ＨP ）構成一動態(tài)冰水循環(huán)水流，儲冰時管內(nèi)鹵水與管外冰水間形成對流傳熱，從而提高結冰均勻度。在溶冰過程由于循環(huán)水流攪動使鹵水與冰水間的靜止水曾流動起來，可有效提高換熱效率，對于溶冰效果具相當助益，降低殘冰量，少量剩余殘冰也會浮到水面而不會卡在盤管之間，防止盤管過度凍結而，使儲冰槽儲冷容量完全發(fā)揮。以上為動態(tài)儲冰槽基本原理，亦為其優(yōu)異之特點。
一般蓄冰槽在盤管內(nèi)側循環(huán)鹵水，盤管外儲水結冰于管壁，由于靜止蓄冰與鹵水熱交換為傳導熱傳模式，因此儲冰效率不佳。在溶冰初期，鹵水管與結冰間管壁冰迅速溶冰成水后逐漸形成鹵水與冰間的靜止水層，成為熱阻抗而使溶冰效率減緩，甚至在溶冰末期雖有剩余冰量，卻無法使用的現(xiàn)象。
二、雙向溶冰速率加倍
動態(tài)蓄冰槽的另一個特點是在溶冰行程可以利用冰水回水動力替代冰水循環(huán)泵，使冰水可由外而內(nèi)直接溶冰供應空調(diào)，再配合鹵水自內(nèi)而外將結冰管溶冰，形成雙向溶冰故效率加倍。
1 . Convective heat exchange is better than conduction
The dynamic ice storage tank is based on the theory that the convective heat exchange is better thsn conduction . The tank has been divided to several chambers by partition and the small circular pump guide Water flow through every chamber up and down circularly , thus the dynamic circulating chilled water flow may arise from minimum power pump ( aboutl～2 HP per tank ) , and then the flow generating the convective heat exchange between inner brine and outer chilled water to raise the freezing effect in charging process . The circulating water flow will agitate steady water layer between brine and chilled water to break resistance in the discharge process of tank . This result will improve discharge effect and exert storage energy in the tank completely . For the description given above , it’s not only the basic theory but also advantage of dynamic ice storage tank .
In general , brine is circulating in the tube and storage water will be frozen on the outer . Because of the heat exchange between still ice and brine is conduction , so that effect of ice charge is poor . In the beginning of discharge , the ice where near the walt of tube is melting rapidly and then generate still water layer as thermal resistance to reduce discharge effect between brine and ice . TO make matters worse , the remanent ice can ' t be melting in the final of discharge process.
2 . Two - way melting ice caused double effect .
The returning chilled water caused power to substitute for the circulating pump is the other character of dynamic ice storage tank . The chilled wster melts ice in the outside and brine in the inside concurrently , two - way melting ice will csuse double effect .
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京ICP080572