鉴于声品质客观评价中，噪声粗糙度算法尚未标准化，本文中提出了改进的 Aures 粗糙度算法(MARA)。选取最大转矩转速(3800r/min)为研究工况，进行了某汽油天然气双燃料发动机的声学性能台架试验。结果表明，燃用汽油时两个测点的声学响应均大于燃用天然气时的声学响应，整机辐射声功率级分别为106.2和103.7dB(A)。但人耳主观感觉却是燃用天然气时的噪声粗糙度比燃用汽油时大。采用MARA客观评价该发动机的噪声粗糙度的结果显示，燃用天然气时测点1和测点2的噪声总粗糙度分别比燃用汽油时大12.2%和4.3%，间接验证了MARA客观评价更接近于人耳主观感觉。%In view of that the noise roughness algorithm has not been standardized in sound quality objective evaluation, a modified Aures roughness algorithm ( MARA ) is proposed in this paper. An acoustic performance bench test on a gasolineatural gas dual fuel engine is conducted at its maximum torque rotating speed of 3 800 r/min. The results indicate that the acoustic responses at two measuring points when fueling gasoline are higher than that when fueling natural gas, and the radiated sound power level of whole engine with different fuels are 106. 2db and 103. 7db respectively. But the subjective perception of human ears is just the opposite, i. e. the noise rough-ness of engine when fueling natural gas is higher than that when fueling gasoline. The results of objective evaluation for engine noise roughness with MARA algorithm show that the overall noise roughness of measuring point 1 and 2 when fueling natural gas are 12. 2% and 4. 3% higher than that when fueling gasoline respectively, indirectly vali-dating that MARA objective evaluation is closer to the subjective hearing sensation of human ears.
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