Roy Douglas’s research while affiliated with Queen's University Belfast and other places

... Under the frequent changes of rich and lean mixture condition, Oxygen Storage Capacity (OSC) happened inside the TWC, and as a result shows in figure 10, NOx didn't emit at the first two times rich condition after the sudden fuel cut condition but emitted after the third time rich condition. OSC makes the catalyst be able to store and release oxygen on the metal and support interface and maintain the conversion efficiency, it can temporarily enable the catalyst to convert CO, THC and NOx in a wider conversion window than normal situation [16]. With the first two times fuel cut condition, there's enough oxygen can be stored into the catalyst, and when the rich condition happened after the fuel cut, the stored oxygen can help three-way catalyst working in an efficient conversion situation and reduced NOx emissions as a result. ...

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Real-world Cold Start Emissions Evaluation for Direct-injection Gasoline Vehicle with PEMS and SEMS

... Their system outperforms traditional methods by efficiently utilizing waste heat across various conditions, demonstrating greater versatility and efficiency in thermal management. Afrasiabian et al. [14] proposed a heat pump system that utilizes waste heat from recirculated air and found that power demand increases by up to 51% without recirculated air. ...

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Integrated Battery Thermal Management and CO2 Control in Electric Buses Using Recirculated Air and Waste Heat Recovery

... Within the engineering and academic spheres, various methods such as bench testing, Computational Fluid Dynamics (CFD) analysis, are commonly utilized to examine the flow field and thermal exchange capabilities within the engine compartment, thereby addressing the issue of enhancing heat transfer. 6,7 Chen et al. 8 utilized the three-dimensional fluid dynamics simulation technique to compute and model the flow and thermal fields of a vehicle under varying conditions influenced by multiple factors. The findings indicated that the intake grille opening ratio and the sealing baffle significantly affect the heat dissipation system. ...

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Thermal management performance analysis and improvement for a commercial vehicle engine compartment through a 1D/3D co-simulation method

... On top of that, for the RHP architecture the ratio between the blower and fan flow rates is expected to be an important parameter as it should affect the potential of the evaporator to recover the heat from the warm air before being vented. Recently, Afrasiabian et al. [39] studied the effects of implementing sliding set-point temperature on the comfort level inside the cabin and the energy consumption, in different ambient temperatures. They showed that when , the power demand would reduce by about 61% for amb = -5 °C setamb = 12 ...

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A numerical evaluation of a novel recovery fresh air heat pump concept for a generic electric bus

... Their experimental results indicated a larger influence on HC oxidation than on CO and an increase in the time required to start the conversion. More recently, Grane et al. [63] aged CCs in a CATAGEN Omega test reactor and used the changes in the light-off curves to determine the deactivation of the CCs (usually, aging moves light-off curves to higher temperatures [64]). ...

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Recent Advances in the Development of Automotive Catalytic Converters: A Systematic Review

... All contributions to the energy budget that apply to the cabin's volume were considered using an accurate model implemented in Simulink ® by accessing Simscape ™ 's libraries, designed explicitly for gaseous thermodynamic problems. A similar model for the cabin volume of a bus was used as a solid base (as described in reference [41]) to construct the model. The construction of the model required the creation of two extreme environments by imposing their pressures and temperatures: the cabin environment (using the 'Constant Volume Chamber (G)' block) and the outdoor ambient (using the 'Temperature Source (G)' block). ...

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Real-Time Implementable Integrated Energy and Cabin Temperature Management for Battery Life Extension in Electric Vehicles

... By contrast, there are lumped models that treat the whole cabin as a single homogeneous zone, primarily intended to assess the impact of the different thermal loads [15] or passenger comfort [16]. Finally, between the two previous types of models, there are those that segment the cabin into several zones, which exchange air volumes, defining lumped models for each one as a simplification of CFD models [17][18][19]; therefore, such exchange mechanisms between adjacent zones must also be mathematically defined. These latter models are a well-suited option for bus or coach cabins, which can be easily partitioned into clearly distinguished air zones, with an optimal balance between accuracy and simplicity with a reasonable computational cost when they are used in the design of control strategies and for real-time simulation. ...

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Design, Implementation and Validation of a Hardware-in-the-Loop Test Bench for Heating Systems in Conventional Coaches

... To date, several numerical and experimental studies have investigated the Heating, Ventilation, and Air Conditioning (HVAC) of passenger vehicles [20,21,22]; however, there is much less research conducted specifically on buses [23,24,25]. Numerical studies have focused on the cabin's thermal conditions, as well as the performance of the HVAC systems, mainly through detailed CFD [21,26] or lumped-parameter models [27,28,29,30,31,22]. Mezrhab and Bouzidi [22] developed a numerical nodal model based on the finite difference method to evaluate the cabin's thermal conditions of a passenger car in summer time. ...

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A numerical evaluation of a novel recovery fresh air heat pump concept for a generic electric bus

... This is expected to increase the power demand remarkably if the conventional control strategies and common control criteria for the cabin condition do not change. Recently Afrasiabian et [5] al. proposed a recovery HP to avoid air recirculation inside the bus and to recover the waste heat before being vented outside. They analysed the energy-saving potential of the recovery HP, compared to a baseline system. ...

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Efficient Heating Strategies Based On Variable Set-Point Temperature of a Bus Cabin with No Air Recirculation

... The previous sections have highlighted the performance reduction occurring when the HP system operates in an intermittent mode to reduce its thermal output and meet the actual building load. The thermal inertia of the water loop (i.e., pipes and TES) is the main technical variable affecting the partial-load inefficiencies [12,13,20,21,34]. It ensures: ...

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A Design methodology for thermal storages in heat pump systems to reduce partial-load losses