{"title":"多孔明胶和纯明胶在冲击状态下的冲击压力、冲击持续时间、压力衰减时间和弹性能量的比较研究","authors":"","doi":"10.1016/j.ijimpeng.2024.105148","DOIUrl":null,"url":null,"abstract":"<div><div>Bird strike is an unavoidable threat in the aviation industry. Real birds are typically replaced with 10 wt. % pure gelatin or porous gelatin to simplify bird strike experiments and meet repeatability requirements. Porous gelatin is obtained by adding chemical agents to gelatin solution, which then solidifies, it can be regarded as pure gelatin filled with tiny pores. The differences in shock state characteristics between these two substitutes remain unclear.</div><div>In this paper, flyer plate impact experiments are conducted separately for the two types of gelatin, obtaining <span><math><mrow><msub><mi>u</mi><mi>s</mi></msub><mo>−</mo><msub><mi>u</mi><mi>p</mi></msub></mrow></math></span>Hugoniot. Considering the continuous release waves, the analytical solutions are provided for the pressure decay time and elastic energy anywhere within the gelatin, during the shock state. Numerical models of gelatin strike rigid target are conducted to extract the shock pressure and elastic energy during the shock state. The differences in mechanical properties of gelatin are analysed to understand that result in variations in pressure, shock duration, decay time, and elastic energy.</div><div>It is evident that the shock pressure of pure gelatin is higher than that of porous gelatin. The shock duration of porous gelatin is longer, and its smaller bulk modulus causes the release wave more gradual, resulting in longer shock decay time. The analytical solution of pressure decay time tends to be overestimated, the faster expansion of porous gelatin during pressure release exacerbates this discrepancy, resulting in a greater difference between the analytical solution and numerical model of elastic energy.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1000,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Comparative investigation of shock pressure, shock duration, pressure decay time, and elastic energy of both porous gelatin and pure gelatin in shock state\",\"authors\":\"\",\"doi\":\"10.1016/j.ijimpeng.2024.105148\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Bird strike is an unavoidable threat in the aviation industry. Real birds are typically replaced with 10 wt. % pure gelatin or porous gelatin to simplify bird strike experiments and meet repeatability requirements. Porous gelatin is obtained by adding chemical agents to gelatin solution, which then solidifies, it can be regarded as pure gelatin filled with tiny pores. The differences in shock state characteristics between these two substitutes remain unclear.</div><div>In this paper, flyer plate impact experiments are conducted separately for the two types of gelatin, obtaining <span><math><mrow><msub><mi>u</mi><mi>s</mi></msub><mo>−</mo><msub><mi>u</mi><mi>p</mi></msub></mrow></math></span>Hugoniot. Considering the continuous release waves, the analytical solutions are provided for the pressure decay time and elastic energy anywhere within the gelatin, during the shock state. Numerical models of gelatin strike rigid target are conducted to extract the shock pressure and elastic energy during the shock state. The differences in mechanical properties of gelatin are analysed to understand that result in variations in pressure, shock duration, decay time, and elastic energy.</div><div>It is evident that the shock pressure of pure gelatin is higher than that of porous gelatin. The shock duration of porous gelatin is longer, and its smaller bulk modulus causes the release wave more gradual, resulting in longer shock decay time. The analytical solution of pressure decay time tends to be overestimated, the faster expansion of porous gelatin during pressure release exacerbates this discrepancy, resulting in a greater difference between the analytical solution and numerical model of elastic energy.</div></div>\",\"PeriodicalId\":50318,\"journal\":{\"name\":\"International Journal of Impact Engineering\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":5.1000,\"publicationDate\":\"2024-10-19\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"International Journal of Impact Engineering\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0734743X24002732\",\"RegionNum\":2,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ENGINEERING, MECHANICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Impact Engineering","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0734743X24002732","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, MECHANICAL","Score":null,"Total":0}
Comparative investigation of shock pressure, shock duration, pressure decay time, and elastic energy of both porous gelatin and pure gelatin in shock state
Bird strike is an unavoidable threat in the aviation industry. Real birds are typically replaced with 10 wt. % pure gelatin or porous gelatin to simplify bird strike experiments and meet repeatability requirements. Porous gelatin is obtained by adding chemical agents to gelatin solution, which then solidifies, it can be regarded as pure gelatin filled with tiny pores. The differences in shock state characteristics between these two substitutes remain unclear.
In this paper, flyer plate impact experiments are conducted separately for the two types of gelatin, obtaining Hugoniot. Considering the continuous release waves, the analytical solutions are provided for the pressure decay time and elastic energy anywhere within the gelatin, during the shock state. Numerical models of gelatin strike rigid target are conducted to extract the shock pressure and elastic energy during the shock state. The differences in mechanical properties of gelatin are analysed to understand that result in variations in pressure, shock duration, decay time, and elastic energy.
It is evident that the shock pressure of pure gelatin is higher than that of porous gelatin. The shock duration of porous gelatin is longer, and its smaller bulk modulus causes the release wave more gradual, resulting in longer shock decay time. The analytical solution of pressure decay time tends to be overestimated, the faster expansion of porous gelatin during pressure release exacerbates this discrepancy, resulting in a greater difference between the analytical solution and numerical model of elastic energy.
期刊介绍:
The International Journal of Impact Engineering, established in 1983 publishes original research findings related to the response of structures, components and materials subjected to impact, blast and high-rate loading. Areas relevant to the journal encompass the following general topics and those associated with them:
-Behaviour and failure of structures and materials under impact and blast loading
-Systems for protection and absorption of impact and blast loading
-Terminal ballistics
-Dynamic behaviour and failure of materials including plasticity and fracture
-Stress waves
-Structural crashworthiness
-High-rate mechanical and forming processes
-Impact, blast and high-rate loading/measurement techniques and their applications