Heating performance simulation of double-wall pipe for aircraft liquid cooling system

摘要

The 65# coolant is generally employed in aircraft liquid cooling system (LCS). However, the obvious rising viscosity of 65# coolant when temperature drops below −40'C always results in some troubles to liquid pump, such as difficulty start up and poor reliability[l]. The exhaust hot air which is discharged from precooler can be applied to heat LCS pipe with advantage of decreasing aircraft performance penalty because of integrated energy management. In this paper, the heat-transfer characteristics of LCS pipe surface is researched seriously and the dynamic simulation of heating performance of hot air for LCS pipe is calculated as well. Two results can be obtained as follows: While mass flow rate of hot air is stable, the heating time is directly proportional to pipe length; While the pipe length is stable, heating time will decrease when the mass flow rate of hot air increases.