In single-phase force convection circumstance to fall, to different equivalent diameter, sectional appearance is flow path respectively the heat exchanger of small measure flow path of rectangle or triangle, it is medium with water and glycol solution, undertake the experiment studies, undertake comparative with the character of going from place to place of heat exchanger of groovy measure flow path, the result makes clear: Coefficient of obstruction of the flow inside small measure flow path under groovy measure flow path, character of obstruction of heat exchanger of rectangular flow path is apparent heat exchanger of excel triangle flow path, factory of coefficient of obstruction of going from place to place increases along with the accretion of equivalent diameter, obstruction coefficient and number of medium cadaver R have nothing to do, the critical Reynolds number that the fluid inside small measure flow path flows is borne in 700, 1200 between. The rate that miniature of electronic system government changes direction to develop is rapidder and rapidder, radiator of tiny flow path comes loose with its hot intensity is high, over all dimension is compact wait for a characteristic to come loose in electronic component hot field and have wide applied perspective. In recent years, a lot of investigator had many job in this domain, tuckennan put forward to use flow path of small rectangular structure in chip underlay the reverse side, use with water force convection refrigeration, medicinal powder heat can amount to M2 of 10 7W ／ to measure level. The research of Wu and Little makes clear as a result: The Moody curve with the classical prep above of factory of coefficient of obstruction of going from place to place of nitrogen, and laminar flow transfers to onflow Re=350, and when the change of heat exchange character occurs in Re=1000. The Pfahler[experiment to fluid, gas makes clear: In the laminar flow flow that already began, (The academic cost that value of F · Re) compares large size flow path is low. The person such as Peng discovers: In single-phase force convection circumstance to fall, have very big effect to factor of obstruction of going from place to place without dimension parameter Z, it is when Z below laminar flow circumstance 0. 5 when attrition factor or obstruction of going from place to place can amount to the least value, turbulence flow obstruction is more adumbrative than classic theory the value is little, the critical number that flow transfers to sufficient progress turbulence also is worth than convention small. A large number of facts make clear: Although the experimental research of the flow inside domestic and international imperceptible flow path and heat exchange got be countinged about naval vessel wait for much experimental data with pressure loss, but the difference with the experimental result constant presence that different investigator gains, even some still exists a lot of qualitative follow with mensurable contradiction. Reason the character that the article explores the liquid in small measure flow path to flow with experimental means, the influence that the element convection such as diameter of sectional appearance, equivalent and sex of content of heat exchange medium uses affirmatory flow path, with period to use a project design and actual production lay a foundation.
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