\u70ed\u91cf\u5982\u4f55\u4f20\u9012\uff1f<\/h1><\/div><\/div><\/div><\/i><\/i><\/span>\u5185\u5bb9\u8f83\u957f\uff0c\u8bf7\u9009\u62e9\u9605\u8bfb<\/span><\/a><\/h4><\/div>- \u70ed\u4f20\u9012\uff08Heat Transfer\uff09<\/a>
- \u70ed\u529b\u5b66\u7b2c\u4e00\u5b9a\u5f8b<\/a><\/li>
- \u70ed\u4f20\u9012\u65b9\u5f0f\uff08Heat Transfer Mechanisms\uff09<\/a><\/li>
- \n\u70ed\u4f20\u5bfc\uff08Conduction\uff09\n<\/a><\/li>
- \n\u70ed\u5bf9\u6d41\uff08Convection\uff09\n<\/a><\/li>
- \n\u70ed\u8f90\u5c04\uff08Radiation\uff09\n<\/a><\/li><\/ul><\/li>
- \u603b\u7ed3<\/a><\/li><\/ul><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div>
\u70ed\u4f20\u9012\uff08Heat Transfer\uff09<\/h2><\/div>\u4f17\u6240\u5468\u77e5\uff0c\u5982\u679c\u6211\u4eec\u5c06\u51b7\u6c34\u74f6\u653e\u5728\u708e\u70ed\u7684\u5730\u65b9\uff0c\u5b83\u4f1a\u53d8\u6696\uff1b\u5982\u679c\u6211\u4eec\u5c06\u51b7\u6c34\u74f6\u653e\u5165\u51b0\u7bb1\uff0c\u6c34\u4f1a\u53d8\u5f97\u66f4\u51b7\u3002\u6211\u4eec\u8fd8\u77e5\u9053\u70ed\u91cf\u4f1a\u4ece\u9ad8\u6e29\u533a\u57df\u4f20\u9012\u5230\u4f4e\u6e29\u533a\u57df\u3002\u8fd9\u79cd\u73b0\u8c61\u5728\u79d1\u5b66\u4e0a\u88ab\u79f0\u4e3a\u201c\u70ed\u4f20\u9012 (Heat Transfer)\u201d\u3002<\/p>\n<\/div>
\u70ed\u529b\u5b66\u7b2c\u4e00\u5b9a\u5f8b<\/h3><\/div>\u70ed\u529b\u5b66\u7b2c\u4e00\u5b9a\u5f8b (The first law of thermodynamics) \u4e5f\u79f0\u4e3a\u201c\u80fd\u91cf\u5b88\u6052\u5b9a\u5f8b (Conservation of energy)\u201d\uff0c\u5b83\u6307\u51fa\u201c\u80fd\u91cf\u65e2\u4e0d\u80fd\u88ab\u521b\u9020\uff0c\u4e5f\u4e0d\u80fd\u88ab\u6bc1\u706d\uff0c\u53ea\u80fd\u4ece\u4e00\u79cd\u5f62\u5f0f\u8f6c\u5316\u4e3a\u53e6\u4e00\u79cd\u5f62\u5f0f\u3002\u201d<\/p>\n
\u6839\u636e\u8fd9\u4e00\u8bf4\u6cd5\uff0c\u53ef\u4ee5\u5199\u51fa\u4ee5\u4e0b\u65b9\u7a0b\u5f0f\uff1a<\/p>\n
(Ein<\/sub>) \u2013 (Eout<\/sub>) = (\u0394Esystem<\/sub>)<\/p>\n\n- Ein<\/sub> <\/span>= \u8f93\u5165\u7cfb\u7edf\u7684\u80fd\u91cf<\/li>\n
- Eout <\/span><\/sub>= \u7cfb\u7edf\u91ca\u653e\u7684\u80fd\u91cf<\/li>\n
- \u0394Esystem <\/sub>= \u7cfb\u7edf\u80fd\u91cf\u53d8\u5316<\/li>\n<\/ul>\n<\/div>
![\"\u70ed\u529b\u5b66\u7b2c\u4e00\u5b9a\u5f8b\"](\"https:\/\/3t-insulation.com\/wp-content\/uploads\/2020\/07\/energy-transfer.png\" "\\"\u80fd\u91cf\u4f20\u9012\\"")
<\/span> <\/div>\u56fe1 \u8bf4\u660e\u80fd\u91cf\u5b88\u6052\u5b9a\u5f8b\u7684\u56fe\u793a\uff0c\u5305\u62ec\u80fd\u91cf\u8f93\u5165\u3001\u8f93\u51fa\u548c\u53d8\u5316\n<\/p><\/div><\/div><\/div>
\u95ed\u5408\u7cfb\u7edf\u7684\u80fd\u91cf\u5e73\u8861\uff08Energy Balance for Close Systems\uff09<\/h4><\/div>\u95ed\u5408\u7cfb\u7edf\uff08Close Systems\uff09\u6307\u8d28\u91cf\u4e0d\u53d8\u7684\u7cfb\u7edf\u3002\u4f8b\u5982\uff0c\u4e00\u7f50\u6e29\u5ea6\u4e3a12\u00b0C\u7684\u6c7d\u6c34\u653e\u572825\u00b0C\u7684\u5ba4\u6e29\u73af\u5883\u4e2d\uff0c\u4e00\u6bb5\u65f6\u95f4\u540e\uff0c\u6c7d\u6c34\u6e29\u5ea6\u5347\u81f320\u00b0C<\/span><\/p>\n\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u53ef\u4ee5\u770b\u51fa\uff0c\u6c7d\u6c34\u7f50\u4e2d\u7684\u6db2\u4f53\u8d28\u91cf\u4fdd\u6301\u4e0d\u53d8\uff0c\u4f46\u7531\u4e8e\u63a5\u6536\u5230\u5916\u90e8\u8f83\u9ad8\u6e29\u5ea6\uff0825\u00b0C\uff09\u7684\u70ed\u91cf\uff0c\u4f7f\u5f97\u6c7d\u6c34\u6e29\u5ea6\u5347\u9ad8\u523020\u00b0C\uff08\u53d8\u70ed\uff09\u3002<\/p>\n
\u6211\u4eec\u53ef\u4ee5\u5199\u51fa\u4ee5\u4e0b\u65b9\u7a0b\u5f0f\uff1a<\/p>\n
(Ein<\/sub>) \u2013 (Eout<\/sub>) = (\u0394Esystem<\/sub>)<\/p>\n\u0394U = mcv<\/sub>\u0394T<\/p>\n\u6216<\/p>\n
Q = mcv<\/sub>\u0394T<\/p>\n\n- \u0394U = <\/span>\u7cfb\u7edf\u80fd\u91cf\u53d8\u5316\uff0c\u5373 \u0394Esystem<\/sub><\/li>\n
- Q = <\/span>\u70ed\u80fd (kJ)<\/li>\n
- m = <\/span>\u7cfb\u7edf\u8d28\u91cf (kg)<\/li>\n
- cv <\/sub>= <\/span>\u6bd4\u70ed\u5bb9 (kJ\/kg.K) <\/span><\/sub><\/li>\n
- \u0394T = <\/span>\u6e29\u5ea6\u53d8\u5316 (K)<\/li>\n<\/ul>\n<\/div>
![\"\u7f50\u4e2d\u6c34\u7684\u80fd\u91cf\"](\"https:\/\/3t-insulation.com\/wp-content\/uploads\/2020\/07\/amount-of-energy-to-boil-water.png\" "\\"\u5c06\u6c34\u716e\u6cb8\u6240\u9700\u80fd\u91cf\\"")
<\/span> <\/div>\u56fe2 \u7f50\u5b50\u793a\u4f8b\u548c\u8ba1\u7b97\u56fe\u793a\n<\/p><\/div><\/div><\/div>
\u7a33\u6001\u6d41\u52a8\u7cfb\u7edf\u7684\u80fd\u91cf\u5e73\u8861\uff08Steady-Flow System\uff09<\/h4><\/div>\u7a33\u6001\u6d41\u52a8\u7cfb\u7edf\u662f\u6307\u6d41\u5165\u8d28\u91cf\u7b49\u4e8e\u6d41\u51fa\u8d28\u91cf\u7684\u6052\u5b9a\u6d41\u52a8\u7cfb\u7edf\u3002\u4f8b\u5982\u81ea\u6765\u6c34\u7ba1\u4e2d\u7684\u6c34\u6d41\uff0c\u8fdb\u6c34\u53e3\u7684\u6c34\u91cf\u7b49\u4e8e\u51fa\u6c34\u53e3\u7684\u6c34\u91cf\uff0c\u8fd9\u79cd\u7cfb\u7edf\u79f0\u4e3a\u7a33\u6001\u6d41\u52a8\u7cfb\u7edf\u3002<\/p>\n
\u6211\u4eec\u53ef\u4ee5\u5199\u51fa\u4ee5\u4e0b\u65b9\u7a0b\u5f0f\uff1a<\/p>\n
Q\u0307 = \u1e41cv<\/sub>\u0394T<\/p>\n\n- \u0394U = <\/span>\u7cfb\u7edf\u80fd\u91cf\u53d8\u5316\uff0c\u5373 \u0394Esystem<\/sub><\/li>\n
- Q\u0307 = <\/span>\u70ed\u91cf\u4f20\u9012\u7387 (kJ\/s)<\/li>\n
- \u1e41 = <\/span>\u8d28\u91cf\u6d41\u91cf (kg\/s)<\/li>\n
- cv <\/sub>= <\/span>\u6bd4\u70ed\u5bb9 (kJ\/kg.K) <\/span><\/sub><\/li>\n
- \u0394T = <\/span>\u6e29\u5ea6\u53d8\u5316 (K)<\/li>\n<\/ul>\n<\/div>
![\"\u7a33\u6001\u6d41\u52a8\"](\"https:\/\/3t-insulation.com\/wp-content\/uploads\/2020\/07\/steady-Flow-System.png\" "\\"\u7a33\u6001\u6d41\u52a8\u7cfb\u7edf\\"")
<\/span> <\/div>\u56fe3 \u7ba1\u9053\u5185\u6d41\u52a8\u793a\u4f8b\u56fe<\/p><\/div><\/div><\/div><\/div><\/div><\/div><\/div>
\u70ed\u4f20\u9012\u65b9\u5f0f\uff08Heat Transfer Mechanisms\uff09<\/h3><\/div>\u70ed\u91cf\u4ece\u4e00\u4e2a\u533a\u57df\u4f20\u9012\u5230\u53e6\u4e00\u4e2a\u533a\u57df\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u4e09\u79cd\u65b9\u5f0f\uff1a<\/p>\n
\n- \u70ed\u4f20\u5bfc\uff08Conduction\uff09<\/li>\n
- \u70ed\u5bf9\u6d41\uff08Convection\uff09<\/li>\n
- \u70ed\u8f90\u5c04\uff08Radiation\uff09<\/li>\n<\/ol>\n<\/div>
\n- \u70ed\u4f20\u5bfc\uff08Conduction\uff09<\/li>\n<\/ul><\/h3><\/div>
\u8fd9\u662f\u4e00\u79cd\u9700\u8981\u4ecb\u8d28\uff08medium\uff09\u7684\u70ed\u4f20\u9012\u65b9\u5f0f\uff0c\u5305\u62ec\u56fa\u4f53\uff08Solid\uff09\u3001\u6db2\u4f53\uff08Liquid\uff09\u548c\u6c14\u4f53\uff08Gas\uff09\u3002\u8fd9\u4e9b\u4ecb\u8d28\u4fdd\u6301\u9759\u6b62\uff0c\u5f62\u72b6\u56fa\u5b9a\u3002<\/p>\n
\u4f8b\u5982\uff1a<\/p>\n
\n- \u7528\u91d1\u5c5e\u7b77\u5b50\u5939\u706b\u9505\u98df\u6750\u65f6\u624b\u4f1a\u611f\u5230\u53d1\u70ed\uff0c\u8fd9\u662f\u56e0\u4e3a\u91d1\u5c5e\u7b77\u5b50\u63a5\u6536\u70ed\u91cf\u5e76\u4f20\u5bfc\u5230\u6211\u4eec\u7684\u624b\u4e0a\u3002<\/li>\n
- \u5efa\u7b51\u7269\u73bb\u7483\u4e4b\u95f4\u7684\u9759\u6b62\u7a7a\u6c14\uff08Static Air\uff09\u4e5f\u5c5e\u4e8e\u70ed\u4f20\u5bfc\u3002<\/li>\n<\/ul>\n<\/div>
![\"\u901a\u8fc7\u7b77\u5b50\u7684\u70ed\u4f20\u5bfc\"](\"https:\/\/3t-insulation.com\/wp-content\/uploads\/2020\/07\/heat-conduction-in-chopstick.png\" "\\"\u7b77\u5b50\u4e2d\u7684\u70ed\u4f20\u5bfc\\"")
<\/span> <\/div>\u56fe4 \u89e3\u91ca\u70ed\u4f20\u5bfc\u7684\u793a\u4f8b\u56fe\uff0c\u5305\u62ec\u7b77\u5b50\u548c\u706b<\/p><\/div><\/div><\/div>
\u70ed\u5bfc\u7387\uff08Thermal Conductivity or K-Value\uff09<\/h4><\/div>\u6211\u4eec\u90fd\u77e5\u9053\u5403\u706b\u9505\u65f6\u5e94\u8be5\u7528\u6728\u7b77\u800c\u4e0d\u662f\u91d1\u5c5e\u7b77\uff0c\u56e0\u4e3a\u6728\u7b77\u4e0d\u4f1a\u53d8\u70ed\u800c\u91d1\u5c5e\u7b77\u4f1a\u53d8\u70ed\u3002\u90a3\u4e48\uff0c\u8fd9\u662f\u4e3a\u4ec0\u4e48\u5462\uff1f<\/p>\n
\u8fd9\u4e24\u79cd\u7b77\u5b50\u7684\u533a\u522b\u5728\u4e8e\u70ed\u5bfc\u7387\uff08K-Value\uff09\uff0c\u5b83\u8868\u793a\u70ed\u91cf\u80fd\u4f20\u9012\u5230\u53e6\u4e00\u7aef\u7684\u7a0b\u5ea6\uff0c\u8fd9\u53d6\u51b3\u4e8e\u6750\u6599\u7684\u7c7b\u578b\u3002<\/p>\n
\n- \u5982\u679c\u70ed\u5bfc\u7387\u9ad8\uff0c\u610f\u5473\u7740\u80fd\u4f20\u5bfc\u66f4\u591a\u70ed\u91cf\u3002<\/li>\n
- \u5982\u679c\u70ed\u5bfc\u7387\u4f4e\uff0c\u610f\u5473\u7740\u4f20\u5bfc\u7684\u70ed\u91cf\u8f83\u5c11\u3002<\/li>\n<\/ul>\n<\/div>
![\"k\u503c\"](\"https:\/\/3t-insulation.com\/wp-content\/uploads\/2020\/07\/K-conductivity.png\" "\\"\u70ed\u5bfc\u7387\\"")
<\/span> <\/div>\u56fe5 \u9ad8\u4f4e\u70ed\u5bfc\u7387\u6750\u6599\u7684\u5dee\u5f02\u56fe\u793a<\/p><\/div><\/div><\/div>
\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u53ef\u4ee5\u770b\u51fa\uff0c\u201c\u91d1\u5c5e\u201d\u7b77\u5b50\u7684\u5bfc\u70ed\u7cfb\u6570\u9ad8\uff0c\u201c\u6728\u5236\u201d\u7b77\u5b50\u7684\u5bfc\u70ed\u7cfb\u6570\u4f4e\u3002<\/p>\n
\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u516c\u5f0f\u8ba1\u7b97\u70ed\u4f20\u5bfc\u7387\uff1a<\/p>\n
Q\u0307cond<\/sub> = kcond<\/sub> x A x (T1<\/sub> -T2<\/sub>) \/\u0394x<\/p>\n\n- Q\u0307cond <\/sub>= \u70ed\u4f20\u5bfc\u7387 (kJ\/s)<\/li>\n
- kcond <\/sub>= \u70ed\u5bfc\u7387<\/li>\n
- A = \u70ed\u4f20\u9012\u9762\u79ef (m2<\/sup>)<\/li>\n
- T1 <\/sub>= \u6e29\u5ea61 (K)<\/li>\n
- T2 <\/sub>= \u6e29\u5ea62 (K)<\/li>\n
- \u0394x = \u4ecb\u8d28\u539a\u5ea6 (m)<\/li>\n<\/ul>\n<\/div>
![\"\u901a\u8fc7\u5899\u58c1\u7684\u70ed\u4f20\u5bfc\"](\"https:\/\/3t-insulation.com\/wp-content\/uploads\/2020\/07\/cal-heat-conduct.png\" "\\"\u70ed\u4f20\u5bfc\u8ba1\u7b97\\"")
<\/span> <\/div>\u56fe6 \u5e26\u56fe\u793a\u7684\u8ba1\u7b97\u793a\u4f8b<\/p><\/div><\/div><\/div>
\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u6211\u4eec\u53ef\u4ee5\u770b\u5230\uff0c\u5bfc\u70ed\u7cfb\u6570\u8d8a\u4f4e\uff0c\u53e6\u4e00\u4fa7\u7684\u6e29\u5ea6\u5c31\u8d8a\u4f4e\u3002\u56e0\u6b64\uff0c\u6211\u4eec\u6709\u53e6\u4e00\u4e2a\u53d8\u91cf\u79f0\u4e3a\u201c\u70ed\u963b\u7cfb\u6570 (R-Value)\u201d\u3002<\/p>\n<\/div>
\u70ed\u963b\u7cfb\u6570\uff08Thermal Resistance or R-Value\uff09<\/h4><\/div>\u8fd9\u662f\u4e0e\u70ed\u5bfc\u7387\uff08K-Value\uff09\u76f8\u5bf9\u7684\u53c2\u6570<\/span><\/p>\n\n- \u5982\u679c\u70ed\u963b\u7cfb\u6570\u9ad8\uff0c\u8868\u793a\u8be5\u4ecb\u8d28\u5141\u8bb8\u7684\u70ed\u91cf\u4f20\u9012\u8f83\u5c11<\/li>\n
- \u5982\u679c\u70ed\u963b\u7cfb\u6570\u4f4e\uff0c\u8868\u793a\u8be5\u4ecb\u8d28\u5141\u8bb8\u7684\u70ed\u91cf\u4f20\u9012\u8f83\u591a<\/li>\n<\/ul>\n<\/div>
\n- \u70ed\u5bf9\u6d41\uff08Convection\uff09<\/li>\n<\/ul><\/h3><\/div>
\u5bf9\u6d41\u8fc7\u7a0b\u662f\u4f9d\u8d56\u4e8e\u6d41\u52a8\u4ecb\u8d28\u7684\u8fc7\u7a0b\uff0c\u4f8b\u5982\u6db2\u4f53 (Liquid) \u548c\u6c14\u4f53 (Gas)\u3002\u9ad8\u6e29\u90e8\u5206\u4f1a\u4e0a\u5347\uff0c\u4f4e\u6e29\u90e8\u5206\u4f1a\u4e0b\u964d\uff0c\u6b63\u5982\u6211\u4eec\u5e38\u542c\u5230\u7684\u90a3\u6837\uff1a\u201c\u70ed\u7a7a\u6c14\u4e0a\u5347\uff0c\u51b7\u7a7a\u6c14\u4e0b\u964d\u3002\u201d<\/p>\n
\u4f8b\u5982\uff1a<\/p>\n
\n- \u5728\u676f\u4e2d\u716e\u8336\u65f6\uff0c\u6211\u4eec\u53ef\u4ee5\u770b\u5230\u8336\u53f6\u5728\u5782\u76f4\u65b9\u5411\u4e0a\u65cb\u8f6c<\/li>\n
- \u7a7a\u8c03\u538b\u7f29\u673a\u6392\u51fa\u7684\u8f83\u70ed\u7684\u7a7a\u6c14<\/li>\n<\/ul>\n<\/div>
![\"\u6c34\u58f6\u4e2d\u7684\u70ed\u5bf9\u6d41\"](\"https:\/\/3t-insulation.com\/wp-content\/uploads\/2020\/07\/heat-convection-in-kettle.png\" "\\"\u8336\u58f6\u4e2d\u7684\u70ed\u5bf9\u6d41\\"")
<\/span> <\/div>\u8336\u676f\u4e2d\u7684\u70ed\u5bf9\u6d41\u56fe<\/p><\/div><\/div><\/div>
\u70ed\u5bf9\u6d41\u53ef\u4ee5\u6839\u636e\u5176\u7279\u6027\u5206\u4e3a\u4ee5\u4e0b\u7c7b\u578b\uff08\u4ee5\u51b7\u7a7a\u6c14\u4e3a\u4f8b\uff09\uff1a<\/p>\n
\n- \u81ea\u7136\u5bf9\u6d41\uff08Free Convection\/Natural Convection\uff09<\/li>\n
- \u5f3a\u5236\u5bf9\u6d41\uff08Force Convection\uff09<\/li>\n<\/ol>\n
\u4f8b\u5982\uff0c\u5728\u4e00\u4e2a\u975e\u5e38\u708e\u70ed\u7684\u65e5\u5b50\uff0c\u6211\u4eec\u521a\u8fd0\u52a8\u5b8c\u3002\u5982\u679c\u6211\u4eec\u53ea\u662f\u9759\u6b62\u4e0d\u52a8\uff0c\u8fd9\u88ab\u79f0\u4e3a\u201c\u81ea\u7136\u5bf9\u6d41 (Free Convection)\u201d\u3002\u4f46\u5982\u679c\u6211\u4eec\u89c9\u5f97\u592a\u70ed\u53d7\u4e0d\u4e86\uff0c\u9700\u8981\u6253\u5f00\u98ce\u6247\u6765\u5e2e\u52a9\uff0c\u8fd9\u88ab\u79f0\u4e3a\u201c\u5f3a\u5236\u5bf9\u6d41 (Force Convection)\u201d\u3002<\/p>\n<\/div>
![\"\u81ea\u7136\u5bf9\u6d41\u548c\u5f3a\u5236\u5bf9\u6d41\"](\"https:\/\/3t-insulation.com\/wp-content\/uploads\/2020\/07\/forcenatural-convection.png\" "\\"\u5f3a\u5236\u548c\u81ea\u7136\u5bf9\u6d41\\"")
<\/span> <\/div>\u56fe7 \u81ea\u7136\u5bf9\u6d41\u548c\u5f3a\u5236\u5bf9\u6d41\u7684\u56fe\u793a<\/p><\/div><\/div><\/div>
\u5bf9\u6d41\u7cfb\u6570\uff08Convection Coefficient\uff09<\/h4><\/div>\u8fd9\u4e2a\u53c2\u6570\u544a\u8bc9\u6211\u4eec\u5f53\u65f6\u7684\u73af\u5883\u6761\u4ef6\u4e0b\u53ef\u4ee5\u5e26\u8d70\u591a\u5c11\u70ed\u91cf<\/p>\n
\n- \u5982\u679c\u5bf9\u6d41\u7cfb\u6570\u9ad8\uff0c\u610f\u5473\u7740\u6d41\u4f53\u53ef\u4ee5\u5e26\u8d70\u66f4\u591a\u70ed\u91cf<\/li>\n
- \u5982\u679c\u5bf9\u6d41\u7cfb\u6570\u4f4e\uff0c\u610f\u5473\u7740\u6d41\u4f53\u5e26\u8d70\u7684\u70ed\u91cf\u8f83\u5c11<\/li>\n<\/ul>\n<\/div>
![\"\u70ed\u5bf9\u6d41\"](\"https:\/\/3t-insulation.com\/wp-content\/uploads\/2020\/07\/Air-Water-Cool.png\" "\\"\u7a7a\u6c14\u548c\u6c34\u51b7\u5374\\"")
<\/span> <\/div>\u56fe8 \u4e0d\u540c\u6d41\u4f53\u70ed\u91cf\u4f20\u9012\u80fd\u529b\u7684\u56fe\u793a<\/p><\/div><\/div><\/div>
\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u725b\u987f\u51b7\u5374\u5b9a\u5f8b\u8ba1\u7b97\u70ed\u5bf9\u6d41\u7387<\/p>\n
Q\u0307conv<\/sub> = hconv <\/sub>As <\/sub>(Ts<\/sub> -T\u221e<\/sub>)<\/p>\n\n- Q\u0307conv <\/sub>= \u70ed\u5bf9\u6d41\u7387 (kJ\/s)<\/li>\n
- h<\/span>conv <\/sub>= \u5bf9\u6d41\u7cfb\u6570<\/li>\n
- As<\/sub> = \u5bf9\u6d41\u8868\u9762\u79ef (m2<\/sup>)<\/li>\n
- Ts <\/sub>= \u8868\u9762\u6e29\u5ea6 (K)<\/li>\n
- T\u221e <\/sub>= \u6d41\u4f53\u6e29\u5ea6 (K)<\/li>\n<\/ul>\n<\/div>
![\"\u901a\u8fc7\u8868\u9762\u7684\u70ed\u5bf9\u6d41\"](\"https:\/\/3t-insulation.com\/wp-content\/uploads\/2020\/07\/cal-heat-convection.png\" "\\"\u70ed\u5bf9\u6d41\u8ba1\u7b97\\"")
<\/span> <\/div>\u56fe9 \u70ed\u5bf9\u6d41\u8ba1\u7b97\u56fe\u793a<\/p><\/div><\/div><\/div>
\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u6211\u4eec\u53ef\u4ee5\u770b\u51fa\uff0c\u70ed\u5bf9\u6d41\u91cf\u53d6\u51b3\u4e8e\u4ee5\u4e0b\u56e0\u7d20\uff1a<\/p>\n
\n- h<\/span>conv <\/sub>\u70ed\u5bf9\u6d41\u7cfb\u6570<\/li>\n
- As <\/sub>\u8868\u9762\u79ef<\/li>\n
- T\u221e <\/sub>\u6d41\u4f53\u6e29\u5ea6<\/li>\n<\/ol>\n<\/div>
\n- \u70ed\u8f90\u5c04\uff08Radiation\uff09<\/li>\n<\/ul><\/h3><\/div>
<\/i><\/i><\/span>\u5185\u5bb9\u8f83\u957f\uff0c\u8bf7\u9009\u62e9\u9605\u8bfb<\/span><\/a><\/h4><\/div>- \u70ed\u4f20\u9012\uff08Heat Transfer\uff09<\/a>
- \u70ed\u529b\u5b66\u7b2c\u4e00\u5b9a\u5f8b<\/a><\/li>
- \u70ed\u4f20\u9012\u65b9\u5f0f\uff08Heat Transfer Mechanisms\uff09<\/a><\/li>
- \n\u70ed\u4f20\u5bfc\uff08Conduction\uff09\n<\/a><\/li>
- \n\u70ed\u5bf9\u6d41\uff08Convection\uff09\n<\/a><\/li>
- \n\u70ed\u8f90\u5c04\uff08Radiation\uff09\n<\/a><\/li><\/ul><\/li>
- \u603b\u7ed3<\/a><\/li><\/ul><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div>
\u70ed\u4f20\u9012\uff08Heat Transfer\uff09<\/h2><\/div>\u4f17\u6240\u5468\u77e5\uff0c\u5982\u679c\u6211\u4eec\u5c06\u51b7\u6c34\u74f6\u653e\u5728\u708e\u70ed\u7684\u5730\u65b9\uff0c\u5b83\u4f1a\u53d8\u6696\uff1b\u5982\u679c\u6211\u4eec\u5c06\u51b7\u6c34\u74f6\u653e\u5165\u51b0\u7bb1\uff0c\u6c34\u4f1a\u53d8\u5f97\u66f4\u51b7\u3002\u6211\u4eec\u8fd8\u77e5\u9053\u70ed\u91cf\u4f1a\u4ece\u9ad8\u6e29\u533a\u57df\u4f20\u9012\u5230\u4f4e\u6e29\u533a\u57df\u3002\u8fd9\u79cd\u73b0\u8c61\u5728\u79d1\u5b66\u4e0a\u88ab\u79f0\u4e3a\u201c\u70ed\u4f20\u9012 (Heat Transfer)\u201d\u3002<\/p>\n<\/div>
\u70ed\u529b\u5b66\u7b2c\u4e00\u5b9a\u5f8b<\/h3><\/div>\u70ed\u529b\u5b66\u7b2c\u4e00\u5b9a\u5f8b (The first law of thermodynamics) \u4e5f\u79f0\u4e3a\u201c\u80fd\u91cf\u5b88\u6052\u5b9a\u5f8b (Conservation of energy)\u201d\uff0c\u5b83\u6307\u51fa\u201c\u80fd\u91cf\u65e2\u4e0d\u80fd\u88ab\u521b\u9020\uff0c\u4e5f\u4e0d\u80fd\u88ab\u6bc1\u706d\uff0c\u53ea\u80fd\u4ece\u4e00\u79cd\u5f62\u5f0f\u8f6c\u5316\u4e3a\u53e6\u4e00\u79cd\u5f62\u5f0f\u3002\u201d<\/p>\n
\u6839\u636e\u8fd9\u4e00\u8bf4\u6cd5\uff0c\u53ef\u4ee5\u5199\u51fa\u4ee5\u4e0b\u65b9\u7a0b\u5f0f\uff1a<\/p>\n
(Ein<\/sub>) \u2013 (Eout<\/sub>) = (\u0394Esystem<\/sub>)<\/p>\n\n- Ein<\/sub> <\/span>= \u8f93\u5165\u7cfb\u7edf\u7684\u80fd\u91cf<\/li>\n
- Eout <\/span><\/sub>= \u7cfb\u7edf\u91ca\u653e\u7684\u80fd\u91cf<\/li>\n
- \u0394Esystem <\/sub>= \u7cfb\u7edf\u80fd\u91cf\u53d8\u5316<\/li>\n<\/ul>\n<\/div><\/span> <\/div>
\u56fe1 \u8bf4\u660e\u80fd\u91cf\u5b88\u6052\u5b9a\u5f8b\u7684\u56fe\u793a\uff0c\u5305\u62ec\u80fd\u91cf\u8f93\u5165\u3001\u8f93\u51fa\u548c\u53d8\u5316\n<\/p><\/div><\/div><\/div>
\u95ed\u5408\u7cfb\u7edf\u7684\u80fd\u91cf\u5e73\u8861\uff08Energy Balance for Close Systems\uff09<\/h4><\/div>\u95ed\u5408\u7cfb\u7edf\uff08Close Systems\uff09\u6307\u8d28\u91cf\u4e0d\u53d8\u7684\u7cfb\u7edf\u3002\u4f8b\u5982\uff0c\u4e00\u7f50\u6e29\u5ea6\u4e3a12\u00b0C\u7684\u6c7d\u6c34\u653e\u572825\u00b0C\u7684\u5ba4\u6e29\u73af\u5883\u4e2d\uff0c\u4e00\u6bb5\u65f6\u95f4\u540e\uff0c\u6c7d\u6c34\u6e29\u5ea6\u5347\u81f320\u00b0C<\/span><\/p>\n\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u53ef\u4ee5\u770b\u51fa\uff0c\u6c7d\u6c34\u7f50\u4e2d\u7684\u6db2\u4f53\u8d28\u91cf\u4fdd\u6301\u4e0d\u53d8\uff0c\u4f46\u7531\u4e8e\u63a5\u6536\u5230\u5916\u90e8\u8f83\u9ad8\u6e29\u5ea6\uff0825\u00b0C\uff09\u7684\u70ed\u91cf\uff0c\u4f7f\u5f97\u6c7d\u6c34\u6e29\u5ea6\u5347\u9ad8\u523020\u00b0C\uff08\u53d8\u70ed\uff09\u3002<\/p>\n
\u6211\u4eec\u53ef\u4ee5\u5199\u51fa\u4ee5\u4e0b\u65b9\u7a0b\u5f0f\uff1a<\/p>\n
(Ein<\/sub>) \u2013 (Eout<\/sub>) = (\u0394Esystem<\/sub>)<\/p>\n\u0394U = mcv<\/sub>\u0394T<\/p>\n\u6216<\/p>\n
Q = mcv<\/sub>\u0394T<\/p>\n\n- \u0394U = <\/span>\u7cfb\u7edf\u80fd\u91cf\u53d8\u5316\uff0c\u5373 \u0394Esystem<\/sub><\/li>\n
- Q = <\/span>\u70ed\u80fd (kJ)<\/li>\n
- m = <\/span>\u7cfb\u7edf\u8d28\u91cf (kg)<\/li>\n
- cv <\/sub>= <\/span>\u6bd4\u70ed\u5bb9 (kJ\/kg.K) <\/span><\/sub><\/li>\n
- \u0394T = <\/span>\u6e29\u5ea6\u53d8\u5316 (K)<\/li>\n<\/ul>\n<\/div><\/span> <\/div>
\u56fe2 \u7f50\u5b50\u793a\u4f8b\u548c\u8ba1\u7b97\u56fe\u793a\n<\/p><\/div><\/div><\/div>
\u7a33\u6001\u6d41\u52a8\u7cfb\u7edf\u7684\u80fd\u91cf\u5e73\u8861\uff08Steady-Flow System\uff09<\/h4><\/div>\u7a33\u6001\u6d41\u52a8\u7cfb\u7edf\u662f\u6307\u6d41\u5165\u8d28\u91cf\u7b49\u4e8e\u6d41\u51fa\u8d28\u91cf\u7684\u6052\u5b9a\u6d41\u52a8\u7cfb\u7edf\u3002\u4f8b\u5982\u81ea\u6765\u6c34\u7ba1\u4e2d\u7684\u6c34\u6d41\uff0c\u8fdb\u6c34\u53e3\u7684\u6c34\u91cf\u7b49\u4e8e\u51fa\u6c34\u53e3\u7684\u6c34\u91cf\uff0c\u8fd9\u79cd\u7cfb\u7edf\u79f0\u4e3a\u7a33\u6001\u6d41\u52a8\u7cfb\u7edf\u3002<\/p>\n
\u6211\u4eec\u53ef\u4ee5\u5199\u51fa\u4ee5\u4e0b\u65b9\u7a0b\u5f0f\uff1a<\/p>\n
Q\u0307 = \u1e41cv<\/sub>\u0394T<\/p>\n\n- \u0394U = <\/span>\u7cfb\u7edf\u80fd\u91cf\u53d8\u5316\uff0c\u5373 \u0394Esystem<\/sub><\/li>\n
- Q\u0307 = <\/span>\u70ed\u91cf\u4f20\u9012\u7387 (kJ\/s)<\/li>\n
- \u1e41 = <\/span>\u8d28\u91cf\u6d41\u91cf (kg\/s)<\/li>\n
- cv <\/sub>= <\/span>\u6bd4\u70ed\u5bb9 (kJ\/kg.K) <\/span><\/sub><\/li>\n
- \u0394T = <\/span>\u6e29\u5ea6\u53d8\u5316 (K)<\/li>\n<\/ul>\n<\/div><\/span> <\/div>
\u56fe3 \u7ba1\u9053\u5185\u6d41\u52a8\u793a\u4f8b\u56fe<\/p><\/div><\/div><\/div><\/div><\/div><\/div><\/div>
\u70ed\u4f20\u9012\u65b9\u5f0f\uff08Heat Transfer Mechanisms\uff09<\/h3><\/div>\u70ed\u91cf\u4ece\u4e00\u4e2a\u533a\u57df\u4f20\u9012\u5230\u53e6\u4e00\u4e2a\u533a\u57df\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u4e09\u79cd\u65b9\u5f0f\uff1a<\/p>\n
\n- \u70ed\u4f20\u5bfc\uff08Conduction\uff09<\/li>\n
- \u70ed\u5bf9\u6d41\uff08Convection\uff09<\/li>\n
- \u70ed\u8f90\u5c04\uff08Radiation\uff09<\/li>\n<\/ol>\n<\/div>
\n- \u70ed\u4f20\u5bfc\uff08Conduction\uff09<\/li>\n<\/ul><\/h3><\/div>
\u8fd9\u662f\u4e00\u79cd\u9700\u8981\u4ecb\u8d28\uff08medium\uff09\u7684\u70ed\u4f20\u9012\u65b9\u5f0f\uff0c\u5305\u62ec\u56fa\u4f53\uff08Solid\uff09\u3001\u6db2\u4f53\uff08Liquid\uff09\u548c\u6c14\u4f53\uff08Gas\uff09\u3002\u8fd9\u4e9b\u4ecb\u8d28\u4fdd\u6301\u9759\u6b62\uff0c\u5f62\u72b6\u56fa\u5b9a\u3002<\/p>\n
\u4f8b\u5982\uff1a<\/p>\n
\n- \u7528\u91d1\u5c5e\u7b77\u5b50\u5939\u706b\u9505\u98df\u6750\u65f6\u624b\u4f1a\u611f\u5230\u53d1\u70ed\uff0c\u8fd9\u662f\u56e0\u4e3a\u91d1\u5c5e\u7b77\u5b50\u63a5\u6536\u70ed\u91cf\u5e76\u4f20\u5bfc\u5230\u6211\u4eec\u7684\u624b\u4e0a\u3002<\/li>\n
- \u5efa\u7b51\u7269\u73bb\u7483\u4e4b\u95f4\u7684\u9759\u6b62\u7a7a\u6c14\uff08Static Air\uff09\u4e5f\u5c5e\u4e8e\u70ed\u4f20\u5bfc\u3002<\/li>\n<\/ul>\n<\/div><\/span> <\/div>
\u56fe4 \u89e3\u91ca\u70ed\u4f20\u5bfc\u7684\u793a\u4f8b\u56fe\uff0c\u5305\u62ec\u7b77\u5b50\u548c\u706b<\/p><\/div><\/div><\/div>
\u70ed\u5bfc\u7387\uff08Thermal Conductivity or K-Value\uff09<\/h4><\/div>\u6211\u4eec\u90fd\u77e5\u9053\u5403\u706b\u9505\u65f6\u5e94\u8be5\u7528\u6728\u7b77\u800c\u4e0d\u662f\u91d1\u5c5e\u7b77\uff0c\u56e0\u4e3a\u6728\u7b77\u4e0d\u4f1a\u53d8\u70ed\u800c\u91d1\u5c5e\u7b77\u4f1a\u53d8\u70ed\u3002\u90a3\u4e48\uff0c\u8fd9\u662f\u4e3a\u4ec0\u4e48\u5462\uff1f<\/p>\n
\u8fd9\u4e24\u79cd\u7b77\u5b50\u7684\u533a\u522b\u5728\u4e8e\u70ed\u5bfc\u7387\uff08K-Value\uff09\uff0c\u5b83\u8868\u793a\u70ed\u91cf\u80fd\u4f20\u9012\u5230\u53e6\u4e00\u7aef\u7684\u7a0b\u5ea6\uff0c\u8fd9\u53d6\u51b3\u4e8e\u6750\u6599\u7684\u7c7b\u578b\u3002<\/p>\n
\n- \u5982\u679c\u70ed\u5bfc\u7387\u9ad8\uff0c\u610f\u5473\u7740\u80fd\u4f20\u5bfc\u66f4\u591a\u70ed\u91cf\u3002<\/li>\n
- \u5982\u679c\u70ed\u5bfc\u7387\u4f4e\uff0c\u610f\u5473\u7740\u4f20\u5bfc\u7684\u70ed\u91cf\u8f83\u5c11\u3002<\/li>\n<\/ul>\n<\/div><\/span> <\/div>
\u56fe5 \u9ad8\u4f4e\u70ed\u5bfc\u7387\u6750\u6599\u7684\u5dee\u5f02\u56fe\u793a<\/p><\/div><\/div><\/div>
\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u53ef\u4ee5\u770b\u51fa\uff0c\u201c\u91d1\u5c5e\u201d\u7b77\u5b50\u7684\u5bfc\u70ed\u7cfb\u6570\u9ad8\uff0c\u201c\u6728\u5236\u201d\u7b77\u5b50\u7684\u5bfc\u70ed\u7cfb\u6570\u4f4e\u3002<\/p>\n
\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u516c\u5f0f\u8ba1\u7b97\u70ed\u4f20\u5bfc\u7387\uff1a<\/p>\n
Q\u0307cond<\/sub> = kcond<\/sub> x A x (T1<\/sub> -T2<\/sub>) \/\u0394x<\/p>\n\n- Q\u0307cond <\/sub>= \u70ed\u4f20\u5bfc\u7387 (kJ\/s)<\/li>\n
- kcond <\/sub>= \u70ed\u5bfc\u7387<\/li>\n
- A = \u70ed\u4f20\u9012\u9762\u79ef (m2<\/sup>)<\/li>\n
- T1 <\/sub>= \u6e29\u5ea61 (K)<\/li>\n
- T2 <\/sub>= \u6e29\u5ea62 (K)<\/li>\n
- \u0394x = \u4ecb\u8d28\u539a\u5ea6 (m)<\/li>\n<\/ul>\n<\/div><\/span> <\/div>
\u56fe6 \u5e26\u56fe\u793a\u7684\u8ba1\u7b97\u793a\u4f8b<\/p><\/div><\/div><\/div>
\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u6211\u4eec\u53ef\u4ee5\u770b\u5230\uff0c\u5bfc\u70ed\u7cfb\u6570\u8d8a\u4f4e\uff0c\u53e6\u4e00\u4fa7\u7684\u6e29\u5ea6\u5c31\u8d8a\u4f4e\u3002\u56e0\u6b64\uff0c\u6211\u4eec\u6709\u53e6\u4e00\u4e2a\u53d8\u91cf\u79f0\u4e3a\u201c\u70ed\u963b\u7cfb\u6570 (R-Value)\u201d\u3002<\/p>\n<\/div>
\u70ed\u963b\u7cfb\u6570\uff08Thermal Resistance or R-Value\uff09<\/h4><\/div>\u8fd9\u662f\u4e0e\u70ed\u5bfc\u7387\uff08K-Value\uff09\u76f8\u5bf9\u7684\u53c2\u6570<\/span><\/p>\n\n- \u5982\u679c\u70ed\u963b\u7cfb\u6570\u9ad8\uff0c\u8868\u793a\u8be5\u4ecb\u8d28\u5141\u8bb8\u7684\u70ed\u91cf\u4f20\u9012\u8f83\u5c11<\/li>\n
- \u5982\u679c\u70ed\u963b\u7cfb\u6570\u4f4e\uff0c\u8868\u793a\u8be5\u4ecb\u8d28\u5141\u8bb8\u7684\u70ed\u91cf\u4f20\u9012\u8f83\u591a<\/li>\n<\/ul>\n<\/div>
\n- \u70ed\u5bf9\u6d41\uff08Convection\uff09<\/li>\n<\/ul><\/h3><\/div>
\u5bf9\u6d41\u8fc7\u7a0b\u662f\u4f9d\u8d56\u4e8e\u6d41\u52a8\u4ecb\u8d28\u7684\u8fc7\u7a0b\uff0c\u4f8b\u5982\u6db2\u4f53 (Liquid) \u548c\u6c14\u4f53 (Gas)\u3002\u9ad8\u6e29\u90e8\u5206\u4f1a\u4e0a\u5347\uff0c\u4f4e\u6e29\u90e8\u5206\u4f1a\u4e0b\u964d\uff0c\u6b63\u5982\u6211\u4eec\u5e38\u542c\u5230\u7684\u90a3\u6837\uff1a\u201c\u70ed\u7a7a\u6c14\u4e0a\u5347\uff0c\u51b7\u7a7a\u6c14\u4e0b\u964d\u3002\u201d<\/p>\n
\u4f8b\u5982\uff1a<\/p>\n
\n- \u5728\u676f\u4e2d\u716e\u8336\u65f6\uff0c\u6211\u4eec\u53ef\u4ee5\u770b\u5230\u8336\u53f6\u5728\u5782\u76f4\u65b9\u5411\u4e0a\u65cb\u8f6c<\/li>\n
- \u7a7a\u8c03\u538b\u7f29\u673a\u6392\u51fa\u7684\u8f83\u70ed\u7684\u7a7a\u6c14<\/li>\n<\/ul>\n<\/div><\/span> <\/div>
\u8336\u676f\u4e2d\u7684\u70ed\u5bf9\u6d41\u56fe<\/p><\/div><\/div><\/div>
\u70ed\u5bf9\u6d41\u53ef\u4ee5\u6839\u636e\u5176\u7279\u6027\u5206\u4e3a\u4ee5\u4e0b\u7c7b\u578b\uff08\u4ee5\u51b7\u7a7a\u6c14\u4e3a\u4f8b\uff09\uff1a<\/p>\n
\n- \u81ea\u7136\u5bf9\u6d41\uff08Free Convection\/Natural Convection\uff09<\/li>\n
- \u5f3a\u5236\u5bf9\u6d41\uff08Force Convection\uff09<\/li>\n<\/ol>\n
\u4f8b\u5982\uff0c\u5728\u4e00\u4e2a\u975e\u5e38\u708e\u70ed\u7684\u65e5\u5b50\uff0c\u6211\u4eec\u521a\u8fd0\u52a8\u5b8c\u3002\u5982\u679c\u6211\u4eec\u53ea\u662f\u9759\u6b62\u4e0d\u52a8\uff0c\u8fd9\u88ab\u79f0\u4e3a\u201c\u81ea\u7136\u5bf9\u6d41 (Free Convection)\u201d\u3002\u4f46\u5982\u679c\u6211\u4eec\u89c9\u5f97\u592a\u70ed\u53d7\u4e0d\u4e86\uff0c\u9700\u8981\u6253\u5f00\u98ce\u6247\u6765\u5e2e\u52a9\uff0c\u8fd9\u88ab\u79f0\u4e3a\u201c\u5f3a\u5236\u5bf9\u6d41 (Force Convection)\u201d\u3002<\/p>\n<\/div>
<\/span> <\/div>\u56fe7 \u81ea\u7136\u5bf9\u6d41\u548c\u5f3a\u5236\u5bf9\u6d41\u7684\u56fe\u793a<\/p><\/div><\/div><\/div>
\u5bf9\u6d41\u7cfb\u6570\uff08Convection Coefficient\uff09<\/h4><\/div>\u8fd9\u4e2a\u53c2\u6570\u544a\u8bc9\u6211\u4eec\u5f53\u65f6\u7684\u73af\u5883\u6761\u4ef6\u4e0b\u53ef\u4ee5\u5e26\u8d70\u591a\u5c11\u70ed\u91cf<\/p>\n
\n- \u5982\u679c\u5bf9\u6d41\u7cfb\u6570\u9ad8\uff0c\u610f\u5473\u7740\u6d41\u4f53\u53ef\u4ee5\u5e26\u8d70\u66f4\u591a\u70ed\u91cf<\/li>\n
- \u5982\u679c\u5bf9\u6d41\u7cfb\u6570\u4f4e\uff0c\u610f\u5473\u7740\u6d41\u4f53\u5e26\u8d70\u7684\u70ed\u91cf\u8f83\u5c11<\/li>\n<\/ul>\n<\/div><\/span> <\/div>
\u56fe8 \u4e0d\u540c\u6d41\u4f53\u70ed\u91cf\u4f20\u9012\u80fd\u529b\u7684\u56fe\u793a<\/p><\/div><\/div><\/div>
\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u725b\u987f\u51b7\u5374\u5b9a\u5f8b\u8ba1\u7b97\u70ed\u5bf9\u6d41\u7387<\/p>\n
Q\u0307conv<\/sub> = hconv <\/sub>As <\/sub>(Ts<\/sub> -T\u221e<\/sub>)<\/p>\n\n- Q\u0307conv <\/sub>= \u70ed\u5bf9\u6d41\u7387 (kJ\/s)<\/li>\n
- h<\/span>conv <\/sub>= \u5bf9\u6d41\u7cfb\u6570<\/li>\n
- As<\/sub> = \u5bf9\u6d41\u8868\u9762\u79ef (m2<\/sup>)<\/li>\n
- Ts <\/sub>= \u8868\u9762\u6e29\u5ea6 (K)<\/li>\n
- T\u221e <\/sub>= \u6d41\u4f53\u6e29\u5ea6 (K)<\/li>\n<\/ul>\n<\/div><\/span> <\/div>
\u56fe9 \u70ed\u5bf9\u6d41\u8ba1\u7b97\u56fe\u793a<\/p><\/div><\/div><\/div>
\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u6211\u4eec\u53ef\u4ee5\u770b\u51fa\uff0c\u70ed\u5bf9\u6d41\u91cf\u53d6\u51b3\u4e8e\u4ee5\u4e0b\u56e0\u7d20\uff1a<\/p>\n
\n- h<\/span>conv <\/sub>\u70ed\u5bf9\u6d41\u7cfb\u6570<\/li>\n
- As <\/sub>\u8868\u9762\u79ef<\/li>\n
- T\u221e <\/sub>\u6d41\u4f53\u6e29\u5ea6<\/li>\n<\/ol>\n<\/div>
\n- \u70ed\u8f90\u5c04\uff08Radiation\uff09<\/li>\n<\/ul><\/h3><\/div>
- \u70ed\u4f20\u9012\uff08Heat Transfer\uff09<\/a>
- \u70ed\u529b\u5b66\u7b2c\u4e00\u5b9a\u5f8b<\/a><\/li>
- \u70ed\u4f20\u9012\u65b9\u5f0f\uff08Heat Transfer Mechanisms\uff09<\/a><\/li>
- \n\u70ed\u4f20\u5bfc\uff08Conduction\uff09\n<\/a><\/li>
- \n\u70ed\u5bf9\u6d41\uff08Convection\uff09\n<\/a><\/li>
- \n\u70ed\u8f90\u5c04\uff08Radiation\uff09\n<\/a><\/li><\/ul><\/li>
- \u603b\u7ed3<\/a><\/li><\/ul><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div>
\u70ed\u4f20\u9012\uff08Heat Transfer\uff09<\/h2><\/div>
\u4f17\u6240\u5468\u77e5\uff0c\u5982\u679c\u6211\u4eec\u5c06\u51b7\u6c34\u74f6\u653e\u5728\u708e\u70ed\u7684\u5730\u65b9\uff0c\u5b83\u4f1a\u53d8\u6696\uff1b\u5982\u679c\u6211\u4eec\u5c06\u51b7\u6c34\u74f6\u653e\u5165\u51b0\u7bb1\uff0c\u6c34\u4f1a\u53d8\u5f97\u66f4\u51b7\u3002\u6211\u4eec\u8fd8\u77e5\u9053\u70ed\u91cf\u4f1a\u4ece\u9ad8\u6e29\u533a\u57df\u4f20\u9012\u5230\u4f4e\u6e29\u533a\u57df\u3002\u8fd9\u79cd\u73b0\u8c61\u5728\u79d1\u5b66\u4e0a\u88ab\u79f0\u4e3a\u201c\u70ed\u4f20\u9012 (Heat Transfer)\u201d\u3002<\/p>\n<\/div>
\u70ed\u529b\u5b66\u7b2c\u4e00\u5b9a\u5f8b<\/h3><\/div>
\u70ed\u529b\u5b66\u7b2c\u4e00\u5b9a\u5f8b (The first law of thermodynamics) \u4e5f\u79f0\u4e3a\u201c\u80fd\u91cf\u5b88\u6052\u5b9a\u5f8b (Conservation of energy)\u201d\uff0c\u5b83\u6307\u51fa\u201c\u80fd\u91cf\u65e2\u4e0d\u80fd\u88ab\u521b\u9020\uff0c\u4e5f\u4e0d\u80fd\u88ab\u6bc1\u706d\uff0c\u53ea\u80fd\u4ece\u4e00\u79cd\u5f62\u5f0f\u8f6c\u5316\u4e3a\u53e6\u4e00\u79cd\u5f62\u5f0f\u3002\u201d<\/p>\n
\u6839\u636e\u8fd9\u4e00\u8bf4\u6cd5\uff0c\u53ef\u4ee5\u5199\u51fa\u4ee5\u4e0b\u65b9\u7a0b\u5f0f\uff1a<\/p>\n
(Ein<\/sub>) \u2013 (Eout<\/sub>) = (\u0394Esystem<\/sub>)<\/p>\n
- \n
- Ein<\/sub> <\/span>= \u8f93\u5165\u7cfb\u7edf\u7684\u80fd\u91cf<\/li>\n
- Eout <\/span><\/sub>= \u7cfb\u7edf\u91ca\u653e\u7684\u80fd\u91cf<\/li>\n
- \u0394Esystem <\/sub>= \u7cfb\u7edf\u80fd\u91cf\u53d8\u5316<\/li>\n<\/ul>\n<\/div>
<\/span><\/div>\u56fe1 \u8bf4\u660e\u80fd\u91cf\u5b88\u6052\u5b9a\u5f8b\u7684\u56fe\u793a\uff0c\u5305\u62ec\u80fd\u91cf\u8f93\u5165\u3001\u8f93\u51fa\u548c\u53d8\u5316\n<\/p><\/div><\/div><\/div>
\u95ed\u5408\u7cfb\u7edf\u7684\u80fd\u91cf\u5e73\u8861\uff08Energy Balance for Close Systems\uff09<\/h4><\/div>
\u95ed\u5408\u7cfb\u7edf\uff08Close Systems\uff09\u6307\u8d28\u91cf\u4e0d\u53d8\u7684\u7cfb\u7edf\u3002\u4f8b\u5982\uff0c\u4e00\u7f50\u6e29\u5ea6\u4e3a12\u00b0C\u7684\u6c7d\u6c34\u653e\u572825\u00b0C\u7684\u5ba4\u6e29\u73af\u5883\u4e2d\uff0c\u4e00\u6bb5\u65f6\u95f4\u540e\uff0c\u6c7d\u6c34\u6e29\u5ea6\u5347\u81f320\u00b0C<\/span><\/p>\n
\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u53ef\u4ee5\u770b\u51fa\uff0c\u6c7d\u6c34\u7f50\u4e2d\u7684\u6db2\u4f53\u8d28\u91cf\u4fdd\u6301\u4e0d\u53d8\uff0c\u4f46\u7531\u4e8e\u63a5\u6536\u5230\u5916\u90e8\u8f83\u9ad8\u6e29\u5ea6\uff0825\u00b0C\uff09\u7684\u70ed\u91cf\uff0c\u4f7f\u5f97\u6c7d\u6c34\u6e29\u5ea6\u5347\u9ad8\u523020\u00b0C\uff08\u53d8\u70ed\uff09\u3002<\/p>\n
\u6211\u4eec\u53ef\u4ee5\u5199\u51fa\u4ee5\u4e0b\u65b9\u7a0b\u5f0f\uff1a<\/p>\n
(Ein<\/sub>) \u2013 (Eout<\/sub>) = (\u0394Esystem<\/sub>)<\/p>\n
\u0394U = mcv<\/sub>\u0394T<\/p>\n
\u6216<\/p>\n
Q = mcv<\/sub>\u0394T<\/p>\n
- \n
- \u0394U = <\/span>\u7cfb\u7edf\u80fd\u91cf\u53d8\u5316\uff0c\u5373 \u0394Esystem<\/sub><\/li>\n
- Q = <\/span>\u70ed\u80fd (kJ)<\/li>\n
- m = <\/span>\u7cfb\u7edf\u8d28\u91cf (kg)<\/li>\n
- cv <\/sub>= <\/span>\u6bd4\u70ed\u5bb9 (kJ\/kg.K) <\/span><\/sub><\/li>\n
- \u0394T = <\/span>\u6e29\u5ea6\u53d8\u5316 (K)<\/li>\n<\/ul>\n<\/div>
<\/span><\/div>\u56fe2 \u7f50\u5b50\u793a\u4f8b\u548c\u8ba1\u7b97\u56fe\u793a\n<\/p><\/div><\/div><\/div>
\u7a33\u6001\u6d41\u52a8\u7cfb\u7edf\u7684\u80fd\u91cf\u5e73\u8861\uff08Steady-Flow System\uff09<\/h4><\/div>
\u7a33\u6001\u6d41\u52a8\u7cfb\u7edf\u662f\u6307\u6d41\u5165\u8d28\u91cf\u7b49\u4e8e\u6d41\u51fa\u8d28\u91cf\u7684\u6052\u5b9a\u6d41\u52a8\u7cfb\u7edf\u3002\u4f8b\u5982\u81ea\u6765\u6c34\u7ba1\u4e2d\u7684\u6c34\u6d41\uff0c\u8fdb\u6c34\u53e3\u7684\u6c34\u91cf\u7b49\u4e8e\u51fa\u6c34\u53e3\u7684\u6c34\u91cf\uff0c\u8fd9\u79cd\u7cfb\u7edf\u79f0\u4e3a\u7a33\u6001\u6d41\u52a8\u7cfb\u7edf\u3002<\/p>\n
\u6211\u4eec\u53ef\u4ee5\u5199\u51fa\u4ee5\u4e0b\u65b9\u7a0b\u5f0f\uff1a<\/p>\n
Q\u0307 = \u1e41cv<\/sub>\u0394T<\/p>\n
- \n
- \u0394U = <\/span>\u7cfb\u7edf\u80fd\u91cf\u53d8\u5316\uff0c\u5373 \u0394Esystem<\/sub><\/li>\n
- Q\u0307 = <\/span>\u70ed\u91cf\u4f20\u9012\u7387 (kJ\/s)<\/li>\n
- \u1e41 = <\/span>\u8d28\u91cf\u6d41\u91cf (kg\/s)<\/li>\n
- cv <\/sub>= <\/span>\u6bd4\u70ed\u5bb9 (kJ\/kg.K) <\/span><\/sub><\/li>\n
- \u0394T = <\/span>\u6e29\u5ea6\u53d8\u5316 (K)<\/li>\n<\/ul>\n<\/div>
<\/span><\/div>\u56fe3 \u7ba1\u9053\u5185\u6d41\u52a8\u793a\u4f8b\u56fe<\/p><\/div><\/div><\/div><\/div><\/div><\/div><\/div>
\u70ed\u4f20\u9012\u65b9\u5f0f\uff08Heat Transfer Mechanisms\uff09<\/h3><\/div>
\u70ed\u91cf\u4ece\u4e00\u4e2a\u533a\u57df\u4f20\u9012\u5230\u53e6\u4e00\u4e2a\u533a\u57df\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u4e09\u79cd\u65b9\u5f0f\uff1a<\/p>\n
- \n
- \u70ed\u4f20\u5bfc\uff08Conduction\uff09<\/li>\n
- \u70ed\u5bf9\u6d41\uff08Convection\uff09<\/li>\n
- \u70ed\u8f90\u5c04\uff08Radiation\uff09<\/li>\n<\/ol>\n<\/div>
- \n
- \u70ed\u4f20\u5bfc\uff08Conduction\uff09<\/li>\n<\/ul><\/h3><\/div>
\u8fd9\u662f\u4e00\u79cd\u9700\u8981\u4ecb\u8d28\uff08medium\uff09\u7684\u70ed\u4f20\u9012\u65b9\u5f0f\uff0c\u5305\u62ec\u56fa\u4f53\uff08Solid\uff09\u3001\u6db2\u4f53\uff08Liquid\uff09\u548c\u6c14\u4f53\uff08Gas\uff09\u3002\u8fd9\u4e9b\u4ecb\u8d28\u4fdd\u6301\u9759\u6b62\uff0c\u5f62\u72b6\u56fa\u5b9a\u3002<\/p>\n
\u4f8b\u5982\uff1a<\/p>\n
- \n
- \u7528\u91d1\u5c5e\u7b77\u5b50\u5939\u706b\u9505\u98df\u6750\u65f6\u624b\u4f1a\u611f\u5230\u53d1\u70ed\uff0c\u8fd9\u662f\u56e0\u4e3a\u91d1\u5c5e\u7b77\u5b50\u63a5\u6536\u70ed\u91cf\u5e76\u4f20\u5bfc\u5230\u6211\u4eec\u7684\u624b\u4e0a\u3002<\/li>\n
- \u5efa\u7b51\u7269\u73bb\u7483\u4e4b\u95f4\u7684\u9759\u6b62\u7a7a\u6c14\uff08Static Air\uff09\u4e5f\u5c5e\u4e8e\u70ed\u4f20\u5bfc\u3002<\/li>\n<\/ul>\n<\/div><\/span><\/div>
\u56fe4 \u89e3\u91ca\u70ed\u4f20\u5bfc\u7684\u793a\u4f8b\u56fe\uff0c\u5305\u62ec\u7b77\u5b50\u548c\u706b<\/p><\/div><\/div><\/div>
\u70ed\u5bfc\u7387\uff08Thermal Conductivity or K-Value\uff09<\/h4><\/div>
\u6211\u4eec\u90fd\u77e5\u9053\u5403\u706b\u9505\u65f6\u5e94\u8be5\u7528\u6728\u7b77\u800c\u4e0d\u662f\u91d1\u5c5e\u7b77\uff0c\u56e0\u4e3a\u6728\u7b77\u4e0d\u4f1a\u53d8\u70ed\u800c\u91d1\u5c5e\u7b77\u4f1a\u53d8\u70ed\u3002\u90a3\u4e48\uff0c\u8fd9\u662f\u4e3a\u4ec0\u4e48\u5462\uff1f<\/p>\n
\u8fd9\u4e24\u79cd\u7b77\u5b50\u7684\u533a\u522b\u5728\u4e8e\u70ed\u5bfc\u7387\uff08K-Value\uff09\uff0c\u5b83\u8868\u793a\u70ed\u91cf\u80fd\u4f20\u9012\u5230\u53e6\u4e00\u7aef\u7684\u7a0b\u5ea6\uff0c\u8fd9\u53d6\u51b3\u4e8e\u6750\u6599\u7684\u7c7b\u578b\u3002<\/p>\n
- \n
- \u5982\u679c\u70ed\u5bfc\u7387\u9ad8\uff0c\u610f\u5473\u7740\u80fd\u4f20\u5bfc\u66f4\u591a\u70ed\u91cf\u3002<\/li>\n
- \u5982\u679c\u70ed\u5bfc\u7387\u4f4e\uff0c\u610f\u5473\u7740\u4f20\u5bfc\u7684\u70ed\u91cf\u8f83\u5c11\u3002<\/li>\n<\/ul>\n<\/div><\/span><\/div>
\u56fe5 \u9ad8\u4f4e\u70ed\u5bfc\u7387\u6750\u6599\u7684\u5dee\u5f02\u56fe\u793a<\/p><\/div><\/div><\/div>
\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u53ef\u4ee5\u770b\u51fa\uff0c\u201c\u91d1\u5c5e\u201d\u7b77\u5b50\u7684\u5bfc\u70ed\u7cfb\u6570\u9ad8\uff0c\u201c\u6728\u5236\u201d\u7b77\u5b50\u7684\u5bfc\u70ed\u7cfb\u6570\u4f4e\u3002<\/p>\n
\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u516c\u5f0f\u8ba1\u7b97\u70ed\u4f20\u5bfc\u7387\uff1a<\/p>\n
Q\u0307cond<\/sub> = kcond<\/sub> x A x (T1<\/sub> -T2<\/sub>) \/\u0394x<\/p>\n
- \n
- Q\u0307cond <\/sub>= \u70ed\u4f20\u5bfc\u7387 (kJ\/s)<\/li>\n
- kcond <\/sub>= \u70ed\u5bfc\u7387<\/li>\n
- A = \u70ed\u4f20\u9012\u9762\u79ef (m2<\/sup>)<\/li>\n
- T1 <\/sub>= \u6e29\u5ea61 (K)<\/li>\n
- T2 <\/sub>= \u6e29\u5ea62 (K)<\/li>\n
- \u0394x = \u4ecb\u8d28\u539a\u5ea6 (m)<\/li>\n<\/ul>\n<\/div>
<\/span><\/div>\u56fe6 \u5e26\u56fe\u793a\u7684\u8ba1\u7b97\u793a\u4f8b<\/p><\/div><\/div><\/div>
\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u6211\u4eec\u53ef\u4ee5\u770b\u5230\uff0c\u5bfc\u70ed\u7cfb\u6570\u8d8a\u4f4e\uff0c\u53e6\u4e00\u4fa7\u7684\u6e29\u5ea6\u5c31\u8d8a\u4f4e\u3002\u56e0\u6b64\uff0c\u6211\u4eec\u6709\u53e6\u4e00\u4e2a\u53d8\u91cf\u79f0\u4e3a\u201c\u70ed\u963b\u7cfb\u6570 (R-Value)\u201d\u3002<\/p>\n<\/div>
\u70ed\u963b\u7cfb\u6570\uff08Thermal Resistance or R-Value\uff09<\/h4><\/div>
\u8fd9\u662f\u4e0e\u70ed\u5bfc\u7387\uff08K-Value\uff09\u76f8\u5bf9\u7684\u53c2\u6570<\/span><\/p>\n
- \n
- \u5982\u679c\u70ed\u963b\u7cfb\u6570\u9ad8\uff0c\u8868\u793a\u8be5\u4ecb\u8d28\u5141\u8bb8\u7684\u70ed\u91cf\u4f20\u9012\u8f83\u5c11<\/li>\n
- \u5982\u679c\u70ed\u963b\u7cfb\u6570\u4f4e\uff0c\u8868\u793a\u8be5\u4ecb\u8d28\u5141\u8bb8\u7684\u70ed\u91cf\u4f20\u9012\u8f83\u591a<\/li>\n<\/ul>\n<\/div>
- \n
- \u70ed\u5bf9\u6d41\uff08Convection\uff09<\/li>\n<\/ul><\/h3><\/div>
\u5bf9\u6d41\u8fc7\u7a0b\u662f\u4f9d\u8d56\u4e8e\u6d41\u52a8\u4ecb\u8d28\u7684\u8fc7\u7a0b\uff0c\u4f8b\u5982\u6db2\u4f53 (Liquid) \u548c\u6c14\u4f53 (Gas)\u3002\u9ad8\u6e29\u90e8\u5206\u4f1a\u4e0a\u5347\uff0c\u4f4e\u6e29\u90e8\u5206\u4f1a\u4e0b\u964d\uff0c\u6b63\u5982\u6211\u4eec\u5e38\u542c\u5230\u7684\u90a3\u6837\uff1a\u201c\u70ed\u7a7a\u6c14\u4e0a\u5347\uff0c\u51b7\u7a7a\u6c14\u4e0b\u964d\u3002\u201d<\/p>\n
\u4f8b\u5982\uff1a<\/p>\n
- \n
- \u5728\u676f\u4e2d\u716e\u8336\u65f6\uff0c\u6211\u4eec\u53ef\u4ee5\u770b\u5230\u8336\u53f6\u5728\u5782\u76f4\u65b9\u5411\u4e0a\u65cb\u8f6c<\/li>\n
- \u7a7a\u8c03\u538b\u7f29\u673a\u6392\u51fa\u7684\u8f83\u70ed\u7684\u7a7a\u6c14<\/li>\n<\/ul>\n<\/div><\/span><\/div>
\u8336\u676f\u4e2d\u7684\u70ed\u5bf9\u6d41\u56fe<\/p><\/div><\/div><\/div>
\u70ed\u5bf9\u6d41\u53ef\u4ee5\u6839\u636e\u5176\u7279\u6027\u5206\u4e3a\u4ee5\u4e0b\u7c7b\u578b\uff08\u4ee5\u51b7\u7a7a\u6c14\u4e3a\u4f8b\uff09\uff1a<\/p>\n
- \n
- \u81ea\u7136\u5bf9\u6d41\uff08Free Convection\/Natural Convection\uff09<\/li>\n
- \u5f3a\u5236\u5bf9\u6d41\uff08Force Convection\uff09<\/li>\n<\/ol>\n
\u4f8b\u5982\uff0c\u5728\u4e00\u4e2a\u975e\u5e38\u708e\u70ed\u7684\u65e5\u5b50\uff0c\u6211\u4eec\u521a\u8fd0\u52a8\u5b8c\u3002\u5982\u679c\u6211\u4eec\u53ea\u662f\u9759\u6b62\u4e0d\u52a8\uff0c\u8fd9\u88ab\u79f0\u4e3a\u201c\u81ea\u7136\u5bf9\u6d41 (Free Convection)\u201d\u3002\u4f46\u5982\u679c\u6211\u4eec\u89c9\u5f97\u592a\u70ed\u53d7\u4e0d\u4e86\uff0c\u9700\u8981\u6253\u5f00\u98ce\u6247\u6765\u5e2e\u52a9\uff0c\u8fd9\u88ab\u79f0\u4e3a\u201c\u5f3a\u5236\u5bf9\u6d41 (Force Convection)\u201d\u3002<\/p>\n<\/div>
<\/span><\/div>\u56fe7 \u81ea\u7136\u5bf9\u6d41\u548c\u5f3a\u5236\u5bf9\u6d41\u7684\u56fe\u793a<\/p><\/div><\/div><\/div>
\u5bf9\u6d41\u7cfb\u6570\uff08Convection Coefficient\uff09<\/h4><\/div>
\u8fd9\u4e2a\u53c2\u6570\u544a\u8bc9\u6211\u4eec\u5f53\u65f6\u7684\u73af\u5883\u6761\u4ef6\u4e0b\u53ef\u4ee5\u5e26\u8d70\u591a\u5c11\u70ed\u91cf<\/p>\n
- \n
- \u5982\u679c\u5bf9\u6d41\u7cfb\u6570\u9ad8\uff0c\u610f\u5473\u7740\u6d41\u4f53\u53ef\u4ee5\u5e26\u8d70\u66f4\u591a\u70ed\u91cf<\/li>\n
- \u5982\u679c\u5bf9\u6d41\u7cfb\u6570\u4f4e\uff0c\u610f\u5473\u7740\u6d41\u4f53\u5e26\u8d70\u7684\u70ed\u91cf\u8f83\u5c11<\/li>\n<\/ul>\n<\/div><\/span><\/div>
\u56fe8 \u4e0d\u540c\u6d41\u4f53\u70ed\u91cf\u4f20\u9012\u80fd\u529b\u7684\u56fe\u793a<\/p><\/div><\/div><\/div>
\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u725b\u987f\u51b7\u5374\u5b9a\u5f8b\u8ba1\u7b97\u70ed\u5bf9\u6d41\u7387<\/p>\n
Q\u0307conv<\/sub> = hconv <\/sub>As <\/sub>(Ts<\/sub> -T\u221e<\/sub>)<\/p>\n
- \n
- Q\u0307conv <\/sub>= \u70ed\u5bf9\u6d41\u7387 (kJ\/s)<\/li>\n
- h<\/span>conv <\/sub>= \u5bf9\u6d41\u7cfb\u6570<\/li>\n
- As<\/sub> = \u5bf9\u6d41\u8868\u9762\u79ef (m2<\/sup>)<\/li>\n
- Ts <\/sub>= \u8868\u9762\u6e29\u5ea6 (K)<\/li>\n
- T\u221e <\/sub>= \u6d41\u4f53\u6e29\u5ea6 (K)<\/li>\n<\/ul>\n<\/div>
<\/span><\/div>\u56fe9 \u70ed\u5bf9\u6d41\u8ba1\u7b97\u56fe\u793a<\/p><\/div><\/div><\/div>
\u4ece\u8fd9\u4e2a\u4f8b\u5b50\u6211\u4eec\u53ef\u4ee5\u770b\u51fa\uff0c\u70ed\u5bf9\u6d41\u91cf\u53d6\u51b3\u4e8e\u4ee5\u4e0b\u56e0\u7d20\uff1a<\/p>\n
- \n
- h<\/span>conv <\/sub>\u70ed\u5bf9\u6d41\u7cfb\u6570<\/li>\n
- As <\/sub>\u8868\u9762\u79ef<\/li>\n
- T\u221e <\/sub>\u6d41\u4f53\u6e29\u5ea6<\/li>\n<\/ol>\n<\/div>
- \n
- \u70ed\u8f90\u5c04\uff08Radiation\uff09<\/li>\n<\/ul><\/h3><\/div>
- As <\/sub>\u8868\u9762\u79ef<\/li>\n
- h<\/span>conv <\/sub>= \u5bf9\u6d41\u7cfb\u6570<\/li>\n
- Q\u0307conv <\/sub>= \u70ed\u5bf9\u6d41\u7387 (kJ\/s)<\/li>\n
- \u70ed\u5bf9\u6d41\uff08Convection\uff09<\/li>\n<\/ul><\/h3><\/div>
- kcond <\/sub>= \u70ed\u5bfc\u7387<\/li>\n
- Q\u0307cond <\/sub>= \u70ed\u4f20\u5bfc\u7387 (kJ\/s)<\/li>\n
- \u70ed\u4f20\u5bfc\uff08Conduction\uff09<\/li>\n<\/ul><\/h3><\/div>
- Q\u0307 = <\/span>\u70ed\u91cf\u4f20\u9012\u7387 (kJ\/s)<\/li>\n
- Q = <\/span>\u70ed\u80fd (kJ)<\/li>\n
- Eout <\/span><\/sub>= \u7cfb\u7edf\u91ca\u653e\u7684\u80fd\u91cf<\/li>\n
- \u70ed\u4f20\u9012\u65b9\u5f0f\uff08Heat Transfer Mechanisms\uff09<\/a><\/li>
- \u70ed\u529b\u5b66\u7b2c\u4e00\u5b9a\u5f8b<\/a><\/li>