TY  - EJOU
AU  - Yang, Shiyu 
AU  - Lin, Yuanfang 
AU  - Qiao, Yancong 
AU  - Zhang, Longfei 
AU  - Yu, Haiyu 
AU  - Xu, Xianghua 
AU  - Liang, Xingang 

TI  - Dynamic Thermal Characteristics of Engine Oil Loop Integrated with Fuel Thermal Management
T2  - Frontiers in Heat and Mass Transfer

PY  - 
VL  - 
IS  - 
SN  - 2151-8629

AB  - The rapid increase in onboard heat loads has made aircraft thermal management a critical issue. As an important part of the fuel thermal management system (FTMS), the dynamic thermal characteristics of the engine oil system (EOS) directly determine temperature regulation and fuel heat sink utilization, necessitating further investigation. In this paper, a novel dynamic heat transfer model for the oil pump was firstly developed through temperature step experiments. Subsequently, a transient flow and heat transfer model of the oil loop was established using the thermal fluid network (TFN) method, and the influence of thermal inertia on thermal response was analyzed. Finally, the impact of the dynamic thermal effects of the EOS on thermal management performance was quantitatively evaluated under an integrated FTMS architecture. Experimental results show significant temperature stratification within the pump body due to large heat conduction resistance. Compared with the single-layer model, the developed double-layer model achieves a 90.25% reduction in temperature prediction errors. In addition, increases in rotational speed and fluid temperature enhance the fluid-solid coupled heat transfer within the pump, while the increase in volumetric efficiency weakens this process. The relative error of the developed empirical correlation for heat transfer within the pump is less than 12%. During operating condition switching, the response delay in thermal parameters can reach 273.7 s, indicating that the fuel supply from the plane needs to be regulated in real time according to the varying oil heat load to prevent both system overtemperature or the waste of fuel heat sink, since the traditional quasi-steady regulation strategy leads to a temperature deviation of up to 4.37 K. Nevertheless, the total heat capacity within the EOS alternately stores and releases heat under a periodic combat mission, with the opposing effects on fuel heat sink consumption canceling each other out. In this case, the integrated FTMS achieves almost the same thermal endurance as that without considering the dynamic thermal effects of the oil loop. Therefore, the thermal inertia of the EOS must be considered in precise temperature control but can be neglected in thermal endurance evaluation. The findings of this paper provide strong support for dynamic thermal modeling of the EOS, system temperature control, and performance evaluation integrated with fuel thermal management.
KW  - Engine oil system; dynamic thermal characteristics; fuel thermal management; gear pump; heat capacity; fuel heat sink; temperature control; thermal endurance

DO  - 10.32604/fhmt.2026.084170