Leakage analysis and concentration distribution of flammable refrigerant R290 in the automobile air conditioner system

A thermal network model for hydrocarbon heat pump systems: A coupling analysis of configuration, working condition, and refrigeration distribution

“…The allowable charge quantity for R290 HPs installed in an enclosed space can only reach the upper charge limits if additional measures such as gas detection and ventilation are implemented [25]. However, such safety precautions impose additional challenges that mainly focus on risk assessments regarding 1) the dynamic behavior of refrigerant leakage and dispersion in room enclosures [26] and 2) refrigerant concentration analyses for other types of compartments (including indoor units [27], cabinets [28], car engines, and passenger spaces [29]). To manage the refrigerant distribution in HP systems, control strategies such as liquid line solenoid valve installation have been investigated, to reduce the risk of leakages that may cause the R290 concentration to exceed the lower flammable limit [30].…”

Research status and future development of thermalmanagement system for new energy vehicles underthe background of carbon neutrality

“…被认定为轻微可燃制冷剂 [78]- [80] ，R1234yf 溶于水可能形成三氟乙酸等 [81] ；甚至，在最新的 研究中，有学者提出 HFO 类制冷剂在大气中会分解产生 CF3CHO(三氟乙醛)，最终分解 产生 CHF3(HFC-23)，HFC-23 是一种强温室效应气体，可能最终导致 HFO 类制冷剂的 GWP 值进行重新评估 [82] 。另外，受限于美国公司的专利保护，R1234yf 高昂的价格 [83] 也是 目前限制其在国内广泛普及的主要问题。 [86] 。在此背景下，虽然很多学者研究并优化了 R290 在车辆制冷系 统内的泄露情况 [87] ，或主张采用多元混合物制冷剂的方式降低 R290 的当量充注量 [88] ，但可 燃性一直是 R290 制冷剂最大的安全隐患。 Since the signing and implementation of the Kigali Amendment to the Montreal Protocol, reducing equivalent carbon emissions and effectively slowing down global warming has become the most appealing topic in various industries worldwide. The total carbon emissions of the transportation industry, which is one of the most important sources of carbon emissions, account for approximately 30% of the total value of the economy and society.…”

CFD simulation of HC-290 leakage from a split type room air conditioner

“…Zhang et al. 19 studied experimentally the concentration of R290 gas leaked into the engine compartment and to the passenger compartment from the HVAC unit of a passenger car. R290 concentration in the environment was above the lower flammable limit (LFL).…”

“…The evaluation of indoor safety during the leaking process show that the combustible zone only appears near the leak hole, and its duration is very short. Zhang et al 19 studied experimentally the concentration of R290 gas leaked into the engine compartment and to the passenger compartment from the HVAC unit of a passenger car. R290 concentration in the environment was above the lower flammable limit (LFL).…”