Experimental investigation on the hysteresis effect in vertical two-phase closed thermosyphons

✍ Scribed by K.S. Ong; Md. Haider-E-Alalhi

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 623 KB
• Volume: 19
• Category: Article
• ISSN: 1359-4311
• DOI: 10.1016/s1359-4311(98)00051-9

✦ Synopsis

Heat pipe heat exchangers (HPHE) are highly ecient heat exchangers employed in heat recovery systems. They are suitably applied for energy recovery in HVAC systems especially in tropical countries where incoming fresh air at high ambient temperatures could be precooled by the cold exhaust air streams. They are also ®nding an increasing application in boiler ¯ue-gas heat recovery systems for preheating incoming combustion air. HPHEs may also be employed for heat recovery from the hot exhaust air in timber drying kilns.

This paper describes work on the hysteresis eect during start up and cooling down of thermosyphon elements in an HPHE, using R-22, R-134a and water as working ¯uids.