CAJ | 학술논문

研制了一种内部中空、外部为齿轮状的木纤维滤芯，建立基于阻力的柴油车尾气微粒捕集器（diesel particulate filter，DPF）滤芯的压力损失和结构参数模型，通过数值计算分析得到新型齿轮状木纤维滤芯的较优尺寸方案；并通过台架试验对不同结构参数滤芯的阻力变化进行对比分析，验证了该新型齿轮状木纤维滤芯的可靠性和科学性。分析结果表明，当DPF过滤室尺寸为直径140 mm、高150 mm时，新型齿轮状木纤维滤芯存在较优结构参数，即齿厚为23.27 mm，齿高为30 mm，齿边夹角为5°，滤芯厚度为7 mm，齿数为8。该文所研制的齿轮型木纤维滤芯对油品质量要求低，过滤阻力小，过滤效率高，价格便宜，且废弃后易于回收再利用。结合温控装置使用，可有效过滤柴油车尾气中的PM，对柴油车尾气净化及环境保护具有十分重要的意义。
연제료일충내부중공、외부위치륜상적목섬유려심，건립기우조력적시유차미기미립포집기（diesel particulate filter，DPF）려심적압력손실화결구삼수모형，통과수치계산분석득도신형치륜상목섬유려심적교우척촌방안；병통과태가시험대불동결구삼수려심적조력변화진행대비분석，험증료해신형치륜상목섬유려심적가고성화과학성。분석결과표명，당DPF과려실척촌위직경140 mm、고150 mm시，신형치륜상목섬유려심존재교우결구삼수，즉치후위23.27 mm，치고위30 mm，치변협각위5°，려심후도위7 mm，치수위8。해문소연제적치륜형목섬유려심대유품질량요구저，과려조력소，과려효솔고，개격편의，차폐기후역우회수재이용。결합온공장치사용，가유효과려시유차미기중적PM，대시유차미기정화급배경보호구유십분중요적의의。
Micron wood fiber is a kind of porous biological materials that can be applied to filter PM emitted by diesel engine. In this paper in order to increase the filtration area and decrease filtration resistance, a wood fiber filter, of which the internal structure was hollow and external structure like gear was developed, the advantages of which were low price, less requirement for diesel quality and large adsorption capacity for PM. In these respects, the gear-shaped wood fiber filter was promising in developing countries where the sulphur content was high in diesel oil. This gear-shaped wood fiber filter can be installed in a detachable DPF case where the temperature inside can be controlled below 220℃ and after reaching the end of its estimated useful lifetime it can be replaced easily. First of all, the pressure loss and structural parameters model of the diesel particulate filter (DPF) based on resistance were built. Referring to the existing research and empirical formula, the filtration resistance of the gear-shaped filters can be expressed by theoretical formula about tooth height, nominal pressure angle and the filter thickness. By analyzing through software Matlab, the tooth height, filter thicknessand nominal pressure angle can be obtained. Furthermore, the tooth thickness and the teeth number can be obtained by some mathematic formula about gear. Then the optimal size of the gear-shaped wood fiber filter was figured out by numerical calculation and analysis. Lastly, the resistance changes of the gear-shaped wood fiber filter with different structural parameters were analyzed by the engine bench. In the test, we developed 8 gear-shaped filters with different structure parameters according to the simulation results and set the speed and the load of the engine kept at 2 200 r/min and 50%. The test results showed that when the diameter and height of the DPF case was 140 and 150 mm respectively, the parameters of the filter, whose tooth thickness was 23.27 mm, tooth height 30 mm, nominal pressure angle 5°, filter thickness 7 mm, teeth number 8 were optimal. This filter had the lowest filtration resistance and increase rate of back pressure, the longest lifetime and the best structure stability. Meanwhile, some other filters whose structural parameters were in the optimal range of parameters also had better filtration performance than those of the rest. According to the test results, it can be known that when the parameters remained in the optimal range, the filtration performances were better and their differences were very small. Furthermore, their filtration efficiency was over 90% and the lifetime was about 90 hours. However, when the parameters were out optimal range, the filtration performances of the gear-shaped wood fiber filter get worse apparently, which definitely proves the reliability and the optimum of the structure parameters of the gear-shaped filter researched in this paper. Above all, the gear-shaped wood fiber filter researched here are low price, less requirement for diesel quality, low filtration resistance, high filtration efficiency, large adsorption capacity and easy to recycle after used. It can filter PM emitted by diesel engine efficiently by combining with temperature control device, which has a reference for environmental protection and purifying diesel exhaust.