振动与冲击
振動與遲擊
진동여충격
JOURNAL OF VIBRATION AND SHOCK
2014年
6期
18-22,34
,共6页
港口%水下爆炸%数值模拟%冲击波%气泡膨胀
港口%水下爆炸%數值模擬%遲擊波%氣泡膨脹
항구%수하폭작%수치모의%충격파%기포팽창
port%underwater explosion%numerical simulation%shock wave%bubble expansion
采用数值仿真方法研究港口水下爆炸荷载的冲击特性,并与经验公式及实验结果比较验证数值模拟方法的正确性;分析水下爆炸冲击波传播过程与气泡膨胀规律。研究表明,港口水下爆炸气泡膨胀荷载不可忽略,由比冲量知,大部分区域气泡膨胀荷载大于冲击波荷载;自由水面对冲击波荷载与气泡膨胀荷载均影响较大,越接近水面二者比冲量越小,气泡膨胀荷载衰减越快,在水面附近其冲量甚至会小于冲击波荷载。水底对气泡膨胀荷载影响不大,而对冲击波荷载影响较大。受水底反射波影响,冲击波作用时间缩短,导致比冲量迅速减小。水底有淤泥层时,冲击波在泥层与水体交界面反射不显著,水底反射冲击波主要来自泥层底部与岩石层分界面。
採用數值倣真方法研究港口水下爆炸荷載的遲擊特性,併與經驗公式及實驗結果比較驗證數值模擬方法的正確性;分析水下爆炸遲擊波傳播過程與氣泡膨脹規律。研究錶明,港口水下爆炸氣泡膨脹荷載不可忽略,由比遲量知,大部分區域氣泡膨脹荷載大于遲擊波荷載;自由水麵對遲擊波荷載與氣泡膨脹荷載均影響較大,越接近水麵二者比遲量越小,氣泡膨脹荷載衰減越快,在水麵附近其遲量甚至會小于遲擊波荷載。水底對氣泡膨脹荷載影響不大,而對遲擊波荷載影響較大。受水底反射波影響,遲擊波作用時間縮短,導緻比遲量迅速減小。水底有淤泥層時,遲擊波在泥層與水體交界麵反射不顯著,水底反射遲擊波主要來自泥層底部與巖石層分界麵。
채용수치방진방법연구항구수하폭작하재적충격특성,병여경험공식급실험결과비교험증수치모의방법적정학성;분석수하폭작충격파전파과정여기포팽창규률。연구표명,항구수하폭작기포팽창하재불가홀략,유비충량지,대부분구역기포팽창하재대우충격파하재;자유수면대충격파하재여기포팽창하재균영향교대,월접근수면이자비충량월소,기포팽창하재쇠감월쾌,재수면부근기충량심지회소우충격파하재。수저대기포팽창하재영향불대,이대충격파하재영향교대。수수저반사파영향,충격파작용시간축단,도치비충량신속감소。수저유어니층시,충격파재니층여수체교계면반사불현저,수저반사충격파주요래자니층저부여암석층분계면。
By numerical simulation,the characteristics of underwater explosion loading in port were investigated. The numerical method was proved by comparing the results with those of the empirical formula and the experiments,then the propagation of shock wave of underwater explosion and the laws of bubble expansion were analyzed.The results show that the loading of bubble expansion in an underwater explosion in port couldn't be ignored.If the loading is scaled by impulse,the loading of bubble expansion is larger than the loading of shock wave in most area.The loading of bubble expansion and shock wave are influenced observably by the water surface,the closer to the water surface,the smaller the impulse of both.But the attenuation of the loading of bubble expansion is faster than that of shock wave,the impulse of bubble expansion even is less than the impulse of shock wave.Water bottom has less influence on the loading of bubble expansion,but has greater influence on the loading of shock wave.The acting time of shock wave would be shortened due to the influence of reflection of water bottom,thereby the impulse of shock wave would reduce rapidly.On the condition of sludge bed in existence,the reflection of shock wave on the interface between sludge bed and water is not remarkable, most of the reflection wave is from the interface between sludge bed and rock.