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The excellent thermal hydraulic performances of coolers are the foundations of vehicular safety and stability. Structure, material, fin type and arrangement all have important effects on the thermal hydraulic performances. Numerical simulation method was adopted in this paper to investigate the effect of fin arrangement. The fluid flow and heat transfer performances were contrasted and analyzed under two different fin arrangements. It was found that fin arrangement effected thermal hydraulic performances severely and during the design process of a cooler, the performance requirements could be met through adjusting fin arrangements.

A radiator is one of the most important components in vehicular cooling system whose excellent fluid flow and heat transfer characteristics guarantees the engine operations. The calculation workload for performance simulation of a whole radiator is too huge due to its size. Experimental study is the conventional method to study radiator performance. This paper put forward a numerical simulation method and radiator heat transfer units were taken as study objects. Orthogonal experiment method was adopted to arrange multi-factor and multi-level calculation schemes. 23 samples with different fin parameters were simulated to investigate their thermal-hydraulic performances. Compared with experimental testing, this method greatly reduced sample manufacturing cost and testing cost, and offered data support for the effect factor study of radiator heat transfer units.

A charged air cooler (CAC) with good thermal-hydraulic performances is the guarantee for vehicular turbo charged air system. Mullti-porus media model is adopted in this study to investigate the thermal-hydraulic performance of a CAC and the effect of its structure on the performance. The detailed fin structure can be simplified and thus computational workload can be reduced greatly by this way, and the overall thermal-hydraulic performance investigation of a CAC is possible. The study results show that the inlet and outlet locations of hot-channel have a significant effect on thermal-hydraulic performance and through changing the locations, heat transfer can be enhanced and flow resistance can be reduced.

The excellent thermal-hydraulic performances of oil cooler are the strong guaranty for automotives’ normal operation. In this study, the thermal-hydraulic performances of compact oil cooler units with different fin size parameters are numerical simulated. According to simulation results, combined with neural networks method, the optimal fin size parameters are determined. Based on this, the effects of different fin arrange layouts on performances are also studied, and optimal layouts for different requirements for flow resistance and heat transfer performances are put forward. This optimal design method can play a guidance role for the designer and manufacturer of heat exchangers.

Visual field of the driver will impact directly on the active safety of the automobile. In this paper, the Chinese eye ellipse in 95th percentile was established based on the modified Chinese physical dimensions data and the equation which is used to position the ellipse with the AHP as the reference point was deduced, providing reference for the design and check work of the automobile visual field. Parameterized model which is used to calculate the blind area in the display zone of the dashboard is built, basing on the Chinese eye ellipse in 95th percentile and its position equation. When the design parameter is changed, the blind area will update synchronously according to the geometric relationship between each dimension, and this characteristic of the model is helpful to avoid redundant design, reduce designers' burden and save time.

Charged air coolers (CAC) are the major components in automotive turbo-charging system. Fin parameters play an important role which affect thermal-hydraulic performances significantly. According to typical fin structures, this paper carried out the matching design of hotside and coldside flow channels in CACs. Based on numerical simulation results, the fluid flow and heat transfer performances of 9 matched CACS were comprehensively evaluated and thus the optimal structure was determined. The results are consistent with engineering practices. This design method can reduce CAC research costs and shorten development period and offer guidance for the designing and manufacturing of CACs.

An Al/Al2O3 gradient coating applied on a heat-resistant stainless steel was prepared through a slurry process by using aluminum and γ-Al2O3 powders as the transition filler material, alpha alumina as the surface coating material, aluminum dihydrogen phosphate as the binder, and sodium molybdate as the corrosion inhibitor. The effects of heat treatment temperature, adhesive/filler ratio and γ-Al2O3 content on the bonding strength, microhardness and thermal shock resistance were investigated. The crystal phase and microstructure were characterized by XRD and SEM. The results indicated that the composition of the coating changed continuously from surface to coating-substrate interface. The coating could offer high bonding strength and good thermal shock resistance when heat treated at 700°C.

The different chrome-free chemical conversion coatings were prepared on AZ91D magnesium alloy and SEM was used to observe the surface. The corrosion behaviors of die-casting AZ91D magnesium alloy with different coating in chloride environment were investigated by hydrogen gas evolution in immersion test, salt spray test and electrochemical measurement. The results showed that the corrosion resistance of magnesium alloy treated with two-step chemical conversion and sealing was the highest and was comparable with that of chromating, and followed by two-step chemical conversion treatment without sealing. The one-step chemical conversion treatment had the lowest corrosion resistance. Polarization and EIS characteristics in 5% NaCl solution depended on the type of surface treatment and correlated well with the order of corrosion resistance. Contrasted with one-step chemical conversion coating, the coating of two-step chemical conversion with sealing on magnesium alloy had more excellent corrosion resistance because the |Z| increased, the corrosion area was decreased and the time of the first pitting occurrence was prolonged. It is expected that this experiment can provide a foundation for designing more super chemical conversion coating to replacing the chromate conversion.