摘要: |
通过对比不同CO2进气压力下4款冷冻活检针中的降温特性,分析进气压力、J-T槽内径、回流通道大小对于活检针降温的影响,并测试其在明胶中形成的冰球大小。结果表明:1.8-0.42 mm、1.8-0.30 mm、1.8-0.12 mm、1.1 mm活检针分别在4.5、4.0、5.5、5.5 MPa的进气压力下降温最快。压力较小时,降温速率与进气压力呈正相关,进气压力大于最佳压力值时,随着压力增大,冰堵加剧;测试的活检针中,较小的J-T槽内径有利于提高活检针的降温速率以及获得更低的刀头温度,较大的回流通道可以减少管内冰堵,提高降温速率;1.8-0.42 mm、1.8-0.30 mm、1.8-0.12 mm、1.1 mm活检针分别在4.5、4.5、6.0、6.0 MPa气源压力下冰球直径最大,当J-T槽的内径减小时,其最佳的气源压力有所增大。 |
关键词: 冷冻活检 J-T效应 降温速率 活检针 |
DOI: |
Received:March 01, 2023Revised:May 03, 2023 |
基金项目:上海市科委项目(20S31903100)资助。 |
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Experimental Study on Throttling and Cooling Characteristics of CO2 in Cryoprobes |
Jin Binhui1,2, Liu Baolin1, Yang Chi3, Xu Binkai3
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(1.Institute of Biothermal and Technology, University of Shanghai for Science and Technology;2.School of Energy and Power Engineering, University of Shanghai for Science and Technology;3.Shanghai Guiding Medical System Co., Ltd.) |
Abstract: |
By comparing the cooling characteristics of four types of cryoprobes under different inlet pressures, the effects of the inlet pressure, J-T slot inner diameter, and backflow channel size on the cooling of cryoprobes are analyzed, and the size of ice hockey balls formed in gelatin are tested. The results show that the temperatures of 1.8–0.42 mm, 1.8–0.30 mm, 1.8–0.12 mm, and 1.1 mm cryoprobes are the fastest under the inlet pressure of 4.5 MPa, 4.0 MPa, 5.5 MPa, and 5.5 MPa, respectively. When the pressure is low, the cooling rate is positively correlated with the inlet pressure. When the inlet pressure is greater than the optimal pressure, the ice blockage increases with increasing pressure. Among the cryoprobes, a smaller inner diameter of the J-T slot improves the cooling rate of the cryoprobes and lowers the temperature of the tip, and a larger backflow channel can reduce ice blockage in the pipe and improve the cooling rate; 1.8–0.42, 1.8–0.30, 1.8–0.12 mm, and 1.1 mm cryoprobes have the largest ice hockey ball diameters under air supply pressures of 4.5, 4.5, 6.0, and 6.0 MPa, respectively. When the inner diameter of the J-T slot decreases, its optimal air supply pressure increases. |
Key words: transbronchial lung cryobiopsy Joule-Thomson effect cooling rate cryoprobe |