發(fā)布時(shí)間：2021-08-14 05:40

　　本文采用實(shí)驗(yàn)方法測(cè)量了水平熱對(duì)流系統(tǒng)中冷熱板上方的局部熱耗散率,實(shí)驗(yàn)中使用特制的由四個(gè)完全相同的熱敏電阻組成的溫度梯度探頭,測(cè)量裝滿水的對(duì)流腔體內(nèi)的無(wú)量綱熱耗散率εN（r）,測(cè)量獲得水平熱對(duì)流系統(tǒng)冷熱板上方在不同Ra數(shù)以及不同垂直空間位置的局部熱耗散率。本實(shí)驗(yàn)使用由四個(gè)直徑為0.36 mm的熱敏電阻組成的溫度梯度探頭,四個(gè)熱敏電阻按直角坐標(biāo)排布。實(shí)驗(yàn)選用的水平對(duì)流發(fā)生裝置是一個(gè)尺寸比為長(zhǎng)（L）:寬（W）:高（H）=10:1:1的長(zhǎng)方體對(duì)流腔體,其長(zhǎng)度、寬度和高度分別是500 mm、50 mm和50 mm。為保證系統(tǒng)與環(huán)境間沒(méi)有熱傳遞,對(duì)流裝置外部由保溫材料包裹,外部絕熱放置于恒溫箱內(nèi),并保持恒溫箱內(nèi)的環(huán)境溫度恒定。實(shí)驗(yàn)系統(tǒng)參數(shù)可通過(guò)調(diào)整冷熱板的溫度來(lái)改變,本實(shí)驗(yàn)中普朗特?cái)?shù)Pr基本維持恒定,約為4.8,瑞利數(shù)Ra的范圍為2×1010～2×1011。根據(jù)GL理論,熱耗散率包含兩個(gè)部分,一項(xiàng)是平均熱耗散率εm（r）,主要受平均溫度梯度的影響;另一項(xiàng)是脈動(dòng)熱耗散率εf（r）,主要來(lái)自于從熱邊界層內(nèi)產(chǎn)生的熱羽流的擬序結(jié)構(gòu)。本文實(shí)驗(yàn)發(fā)現(xiàn),在所研究的Ra數(shù)范圍內(nèi),無(wú)量綱局部熱耗散率εN（r）主要集中... 

【文章來(lái)源】：哈爾濱工業(yè)大學(xué)黑龍江省 211工程院校 985工程院校

【文章頁(yè)數(shù)】：63 頁(yè)

【學(xué)位級(jí)別】：碩士

【文章目錄】：
摘要
Abstract
Acknowledgement
Nomenclature
Chapter1 Introduction
    1.1 Research background
    1.2 Research status quo
    1.3 Research content of this dissertation
Chapter2 Experimental setup
    2.1 Temperature gradient probe
        2.1.1 Assembly of temperature gradient probe
        2.1.2 Calibration of temperature gradient probe
    2.2 Data acquisition module
        2.2.1 Data acquisition board Keysight34901A
        2.2.2 Data collector Keysight34970A
    2.3 Horizontal convection generation device and incubator
        2.3.1 Horizontal convection generation device
        2.3.2 Theoretical analysis based on the device
        2.3.3 Incubator of the system
    2.4 Summary
Chapter3 Measurement stability of temperature gradient porbe
    3.1 Probability density functions of temperature fluctuation
    3.2 Temperature profiles
    3.3 Standard deviation of temperature signals
    3.4 Summary
Chapter4 Thermal dissipation field above the heating plate
    4.1 Vertical spatial distribution of temperature
    4.2 Vertical spatial distributions of local thermal dissipation rate
    4.3 Dependence of thermal dissipation rate and Ra
    4.4 Summary
Chapter5 Thermal dissipation field above the cooling plate
    5.1 Vertical spatial distribution of temperature
    5.2 Vertical spatial distributions of local thermal dissipation rate
    5.3 Summary
Chapter6 Analysis of statistical properties
    6.1 Time series
    6.2 Probability density functions
    6.3 Summary
Conclusions
References


【參考文獻(xiàn)】：
碩士論文
[1]水平熱對(duì)流熱傳輸及溫度剖面的實(shí)驗(yàn)測(cè)量[D]. 鄢博.哈爾濱工業(yè)大學(xué) 2017



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