热扩散率

传热分析中,热扩散率(符号:,但注意都很常用)是热导率容积热容之比。

其中:

  • 热导率单位:W/(m K))
  • 容积热容(单位:J/(m3K))
  • 密度(单位:kg/(m3))
  • 比热容(单位:J/(kg K))

热扩散率的单位是m2/s。

对于普通的岩石来说, ~ 10-6 m2/s。在300K,空气的热扩散率是0.000024 m2/s。

对于空气的热扩散率与绝对温度之间的关系,参见[1]

部分材料與物質的熱擴散率编辑

部分材料與物質的熱擴散率[1]
材質 熱擴散率 (mm2/s) 來源
Pyrolytic graphite, parallel to layers 1220
碳/碳纖維 at 25 °C 216.5 [2]
氦氣 (300 K, 1 atm) 190 [3]
純銀 (99.9%) 165.63
氫氣 (300 K, 1 atm) 160 [3]
127 [4]
at 25 °C 111 [2]
97 [4]
88 [4]
鋁-10矽-錳-鎂 (Silafont 36) at 20 °C 74.2 [5]
6061-T6 鋁合金 64 [4]
(99.95%) at 25 °C 54.3 [6]
鋁-5鎂-2矽-錳 (Magsimal-59) at 20 °C 44.0 [7]
40 [4]
水蒸氣 (1 atm, 400 K) 23.38
23 [4]
氬氣 (300 K, 1 atm) 22 [3]
氮氣 (300 K, 1 atm) 22 [3]
空氣 (300 K) 19 [4]
, AISI 1010 (0.1% carbon) 18.8 [8]
氧化鋁 (polycrystalline) 12.0
, 1% carbon 11.72
Si3N4 with CNTs 26 °C 9.142 [9]
Si3N4 without CNTs 26 °C 8.605 [9]
304不鏽鋼 at 27 °C 4.2 [4]
熱解石墨, normal to layers 3.6
310不鏽鋼 at 25 °C 3.352 [10]
Inconel 600 at 25 °C 3.428 [11]
石英 1.4 [4]
砂岩 1.15
冰 at 0 °C 1.02
二氧化矽 (polycrystalline) 0.83 [4]
磚塊, common 0.52
玻璃窗戶 0.34
磚塊, adobe 0.27
PC塑膠 (polycarbonate) at 25 °C 0.144 [12]
水 at 25 °C 0.143 [12]
PTFE塑膠 (Polytetrafluorethylene) at 25 °C 0.124 [13]
PP塑膠 (polypropylene) at 25 °C 0.096 [12]
尼龍 0.09
橡膠 0.089 - 0.13 [14]
木材 (黃松) 0.082
石蠟 at 25 °C 0.081 [12]
PVC塑膠 (polyvinyl chloride) 0.08 [4]
引擎用油 (saturated liquid, 100 °C) 0.0738
酒精 0.07 [4]


参见编辑

  1. ^ Brown; Marco. Introduction to Heat Transfer 3rd. McGraw-Hill. 1958.  and Eckert; Drake. Heat and Mass Transfer. McGraw-Hill. 1959. ISBN 978-0-89116-553-8.  cited in Holman, J.P. Heat Transfer 9th. McGraw-Hill. 2002. ISBN 978-0-07-029639-8. 
  2. ^ 2.0 2.1 V. Casalegno; P. Vavassori; M. Valle; M. Ferraris; M. Salvo; G. Pintsuk. Measurement of thermal properties of a ceramic/metal joint by laser flash method. Journal of Nuclear Materials. 2010, 407 (2): 83. Bibcode:2010JNuM..407...83C. doi:10.1016/j.jnucmat.2010.09.032. 
  3. ^ 3.0 3.1 3.2 3.3 Lide, David R. (编). CDC Handbook of Chemistry and Physics 71st. Boston: Chemical Rubber Publishing Company. 1992.  cited in Baierlein, Ralph. Thermal Physics . Cambridge, UK: Cambridge University Press. 1999: 372 [1 December 2011]. ISBN 978-0-521-59082-2. 
  4. ^ 4.00 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 4.11 Jim Wilson. Materials Data. August 2007 [2021-11-07]. (原始内容存档于2021-11-08). 
  5. ^ P. Hofer; E. Kaschnitz. Thermal diffusivity of the aluminium alloy Al-10Si-Mn-Mg (Silafont 36) in the solid and liquid states. High Temperatures – High Pressures. 2011, 40 (3–4): 311 [2021-11-07]. (原始内容存档于2016-03-04). 
  6. ^ A. Lindemann; J. Blumm. Measurement of the Thermophysical Properties of Pure Molybdenum. 17th Plansee Seminar 3. 2009. 
  7. ^ E. Kaschnitz; M. Küblböck. Thermal diffusivity of the aluminium alloy Al-5Mg-2Si-Mn (Magsimal-59) in the solid and liquid states. High Temperatures – High Pressures. 2008, 37 (3): 221 [2021-11-07]. (原始内容存档于2016-03-04). 
  8. ^ Lienhard, John H. Lienhard, John H. A Heat Transfer Textbook 5th. Dover Pub. 2019: 715. 
  9. ^ 9.0 9.1 O. Koszor; A. Lindemann; F. Davin; C. Balázsi. Observation of thermophysical and tribological properties of CNT reinforced Si3 N4. Key Engineering Materials. 2009, 409: 354. S2CID 136957396. doi:10.4028/www.scientific.net/KEM.409.354. 
  10. ^ J. Blumm; A. Lindemann; B. Niedrig; R. Campbell. Measurement of Selected Thermophysical Properties of the NPL Certified Reference Material Stainless Steel 310. International Journal of Thermophysics. 2007, 28 (2): 674. Bibcode:2007IJT....28..674B. S2CID 120628607. doi:10.1007/s10765-007-0177-z. 
  11. ^ J. Blumm; A. Lindemann; B. Niedrig. Measurement of the thermophysical properties of an NPL thermal conductivity standard Inconel 600. High Temperatures – High Pressures. 2003–2007, 35/36 (6): 621 [2021-11-07]. doi:10.1068/htjr145. (原始内容存档于2015-09-24). 
  12. ^ 12.0 12.1 12.2 12.3 J. Blumm; A. Lindemann. Characterization of the thermophysical properties of molten polymers and liquids using the flash technique. High Temperatures – High Pressures. 2003–2007, 35/36 (6): 627. doi:10.1068/htjr144. 
  13. ^ J. Blumm; A. Lindemann; M. Meyer; C. Strasser. Characterization of PTFE Using Advanced Thermal Analysis Technique. International Journal of Thermophysics. 2011, 40 (3–4): 311. Bibcode:2010IJT....31.1919B. S2CID 122020437. doi:10.1007/s10765-008-0512-z. 
  14. ^ 引用错误:没有为名为AJP的参考文献提供内容