车用发动机
車用髮動機
차용발동궤
2013年
4期
66-70
,共5页
束卫兵%李庆斌%杨迪%曹刚%闫海东
束衛兵%李慶斌%楊迪%曹剛%閆海東
속위병%리경빈%양적%조강%염해동
涡轮增压器%压气机%负压%密封%漏油
渦輪增壓器%壓氣機%負壓%密封%漏油
와륜증압기%압기궤%부압%밀봉%루유
turbocharger%compressor%negative pressure%sealing%lube oil leakage
采用Numeca数值分析软件建立了某汽油机增压器压气机端流场网格模型,并计算出增压器在低速近堵塞工况下进口压力为负压时压气机性能曲线,对压气机流场分析发现,轮背压力沿径向方向逐渐降低,在轴中心位置附近达到最小值,而在周向方向则变化较小。此外,在不同的转速下,随着进气口负压程度的加大,在轮背建立起来的压力逐渐降低,当进气负压增加到某一值时,若轮背临近密封环处的压力在大气压力附近波动,压气机发生漏油的风险提高。为了验证压气机负压能力预测的准确性,在现有压气机性能测试试验台架上开展了压气机密封性能测试,结果发现,在50000 r/min时,增压器压气机在-6 kPa开始发生漏油,50000 r/min转速下则在-12 kPa发生漏油,模拟分析结果与试验结果存在一些差异,而后就可能存在的原因进行了分析,以完善分析方法,提高增压器产品性能预测能力。
採用Numeca數值分析軟件建立瞭某汽油機增壓器壓氣機耑流場網格模型,併計算齣增壓器在低速近堵塞工況下進口壓力為負壓時壓氣機性能麯線,對壓氣機流場分析髮現,輪揹壓力沿徑嚮方嚮逐漸降低,在軸中心位置附近達到最小值,而在週嚮方嚮則變化較小。此外,在不同的轉速下,隨著進氣口負壓程度的加大,在輪揹建立起來的壓力逐漸降低,噹進氣負壓增加到某一值時,若輪揹臨近密封環處的壓力在大氣壓力附近波動,壓氣機髮生漏油的風險提高。為瞭驗證壓氣機負壓能力預測的準確性,在現有壓氣機性能測試試驗檯架上開展瞭壓氣機密封性能測試,結果髮現,在50000 r/min時,增壓器壓氣機在-6 kPa開始髮生漏油,50000 r/min轉速下則在-12 kPa髮生漏油,模擬分析結果與試驗結果存在一些差異,而後就可能存在的原因進行瞭分析,以完善分析方法,提高增壓器產品性能預測能力。
채용Numeca수치분석연건건립료모기유궤증압기압기궤단류장망격모형,병계산출증압기재저속근도새공황하진구압력위부압시압기궤성능곡선,대압기궤류장분석발현,륜배압력연경향방향축점강저,재축중심위치부근체도최소치,이재주향방향칙변화교소。차외,재불동적전속하,수착진기구부압정도적가대,재륜배건립기래적압력축점강저,당진기부압증가도모일치시,약륜배림근밀봉배처적압력재대기압력부근파동,압기궤발생루유적풍험제고。위료험증압기궤부압능력예측적준학성,재현유압기궤성능측시시험태가상개전료압기궤밀봉성능측시,결과발현,재50000 r/min시,증압기압기궤재-6 kPa개시발생루유,50000 r/min전속하칙재-12 kPa발생루유,모의분석결과여시험결과존재일사차이,이후취가능존재적원인진행료분석,이완선분석방법,제고증압기산품성능예측능력。
The compressor flow field grid model of a gasoline turbocharger was established with Numeca software and the compressor performance curve of negative inlet pressure was calculated under the low speed near choking condition .The com-pressor flow field showed that the pressure inside the back cavity decreased gradually along the radial direction ,reached the min-imum in the vicinity of impeller shaft ,but had little change in the circumferential direction .Under different rotation speeds ,the built pressure in back cavity became lower with the increase of negative inlet pressure .When the negative pressure decreased to a certain value ,the air pressure near the sealing ring fluctuated around the atmospheric pressure and the risk of compressor oil leakage increased .In order to verify the prediction accuracy of compressor negative pressure ability ,the sealing performance testing was carried out on the existing compressor performance test bench .The results show that the lube oil of turbocharger compressor begins to leak under -6 kPa at 50 000 r/min .At 80 000 r/min ,the lube oil begins to leak under -12 kPa .For the difference between test results and simulation results ,the possible reasons were analyzed to improve the analysis method and enhance the performance prediction ability for new design turbocharger products .