基于溫度效應的公路隧道運營通風模式優(yōu)化
發(fā)布時間：2019-01-04 06:38
【摘要】：運營狀態(tài)下的公路隧道通風系統(tǒng)是一個動態(tài)變化的體系。環(huán)境溫度、車速以及交通量的變化,都會引起隧道內(nèi)風壓、風量的動態(tài)變化。在長大深埋公路隧道中,經(jīng)常會碰到高地溫,導致隧道熱位差的變化,對通風系統(tǒng)造成影響,研究隧道以及豎(斜)井內(nèi)風流溫度場分布特征以及復雜隧道通風系統(tǒng)熱位差的計算方法,進而有效利用熱位差和交通風壓,優(yōu)化運營通風模式,達到節(jié)能降耗的目的尤為重要。本文通過國內(nèi)外資料的收集、理論分析、數(shù)值模擬及風網(wǎng)計算等多重手段對高地溫圍巖與風流非穩(wěn)態(tài)傳熱機理、多豎井隧道熱位差計算方法以及風溫、車速與交通量變化時隧道內(nèi)風壓、風量分布特征進行合理分析,并開展了以下研究工作:1.分析了隧道內(nèi)風流溫度變化的影響因素,探明了圍巖與風流非穩(wěn)態(tài)傳熱機理,建立了隧道縱向圍巖與風流非穩(wěn)態(tài)傳熱模型,推導了隧道縱向風流溫度計算公式。采用模型計算某隧道縱向風溫分布,并與現(xiàn)場測試結果對比,驗證了隧道縱向圍巖與風流非穩(wěn)態(tài)傳熱模型的可靠性。2.研究了隧道送風井內(nèi)空氣自壓縮熱、圍巖傳熱和水分蒸發(fā)引起的風流溫度變化計算公式,建立了采用差分法計算送風井和排風井內(nèi)風流溫度的數(shù)學模型。3.分析了隧道內(nèi)外風流溫差引起的熱位差作用機理,基于通風計算原理和連通器基本原理,提出熱位差是重力場作用下空氣柱重度差值引起的風壓,提出采用空氣柱重差法計算隧道內(nèi)熱位差,推導了熱位差的計算公式,結合有限體積法軟件Fluent對有縱坡隧道在空氣柱重力作用下的風壓風量分布特征進行分析,驗證了基于空氣柱重差法的熱位差計算模型的可靠性。4.在fluent中建立相關網(wǎng)格模型,分析了環(huán)境溫度變化對豎井集中排(送)風和分段式排送組合通風的影響,得出了不同環(huán)境溫度、不同通風方式下隧道內(nèi)、排風井和送風井內(nèi)風流的速度、溫度和密度分布特征,結合空氣柱重差法分析了不同通風方式熱位差的變化規(guī)律。5.提出采用計算空氣柱容重結合風網(wǎng)解算的方法研究熱位差和交通風壓變化時隧道內(nèi)風壓風量分布特征,分析了隧道通風網(wǎng)絡中風流的風量平衡定律、風壓平衡定律和阻力定律,建立了隧道風網(wǎng)阻力模型和動力模型,包括通風阻力計算模型、風機風壓計算模型、交通風壓計算模型、自然風壓計算模型、火風壓計算模型和豎井送排式通風計算模型,以節(jié)點法作為基本算法,采用線性迭代計算方法,采用Visual C++語言編寫了基于溫度效應的隧道通風網(wǎng)絡解算程序。6.依托秦嶺終南山公路隧道工程,采用通風網(wǎng)絡解算程序分析了不同環(huán)境溫度、不同車速、不同交通量條件下隧道、排風井和送風井內(nèi)風壓風量分布特征。將計算結果與隧道需風量進行對比,提出了不同運營條件下的優(yōu)化通風模式,可對隧道運營通風決策提供指導。
[Abstract]:The highway tunnel ventilation system is a dynamic system. The change of ambient temperature, speed and traffic volume will cause the dynamic change of wind pressure and air volume in tunnel. In long and deep buried highway tunnels, high ground temperature is often encountered, which results in the variation of tunnel heat potential difference, which has an impact on ventilation system. The distribution characteristics of air flow temperature field in tunnel and vertical (oblique) well and the calculation method of heat potential difference in complex tunnel ventilation system are studied, and the heat potential difference and traffic wind pressure are used effectively to optimize the operation ventilation mode. It is very important to achieve the goal of saving energy and reducing consumption. In this paper, the unsteady heat transfer mechanism of surrounding rock and air flow at high ground temperature, the calculation method of thermal potential difference of multi-shaft tunnel and the wind temperature are studied by means of collecting data, theoretical analysis, numerical simulation and wind net calculation. The distribution characteristics of wind pressure and wind volume in the tunnel are analyzed reasonably when the speed and traffic volume change. The following research work is carried out: 1. The influencing factors of air flow temperature change in tunnel are analyzed, the unsteady heat transfer mechanism of surrounding rock and air flow is proved, the model of tunnel longitudinal surrounding rock and air flow unsteady state heat transfer is established, and the calculation formula of tunnel longitudinal air flow temperature is deduced. The model is used to calculate the longitudinal wind temperature distribution of a tunnel, and compared with the field test results, the reliability of the tunnel longitudinal surrounding rock and wind flow unsteady heat transfer model is verified. 2. The formula of air flow temperature change caused by air self-compression heat, surrounding rock heat transfer and water evaporation in tunnel air supply well is studied, and a mathematical model for calculating air flow temperature in air supply well and exhaust air well by using difference method is established. The mechanism of thermal potential difference caused by air flow temperature difference inside and outside the tunnel is analyzed. Based on the principle of ventilation calculation and the basic principle of connectors, it is proposed that the thermal potential difference is the wind pressure caused by the heavy difference of air column under the action of gravity field. The air column weight difference method is used to calculate the thermal potential difference in the tunnel. The calculation formula of the thermal potential difference is derived, and the wind pressure and air volume distribution characteristics of the longitudinal slope tunnel under the action of air column gravity are analyzed in combination with the finite volume method software Fluent. The reliability of the thermal potential difference calculation model based on the air column weight difference method is verified. 4. 4. The related grid model is established in fluent, and the influence of ambient temperature change on the combined ventilation of centralized ventilation and segmental ventilation in shaft is analyzed. The results show that there are different ambient temperatures and different ventilation modes in the tunnel. The distribution characteristics of air flow velocity, temperature and density in exhaust and air supply wells are analyzed, and the variation law of heat potential difference in different ventilation modes is analyzed in combination with the air column weight difference method. 5. A method of calculating air column bulk density combined with wind network solution is proposed to study the distribution characteristics of wind pressure in tunnel when heat potential difference and traffic wind pressure change. The wind flow balance law, wind pressure balance law and resistance law in tunnel ventilation network are analyzed. The resistance model and dynamic model of tunnel wind network are established, including ventilation resistance calculation model, fan wind pressure calculation model, traffic wind pressure calculation model, natural wind pressure calculation model, fire wind pressure calculation model and shaft ventilation calculation model. The node method is taken as the basic algorithm, the linear iterative calculation method is adopted, and the program of tunnel ventilation network calculation based on temperature effect is written by Visual C language. 6. Based on the Qinling Zhongnanshan Highway Tunnel Project, the distribution characteristics of air pressure in tunnel, exhaust well and air supply well under different ambient temperature, different speed and different traffic volume are analyzed by using ventilation network calculation program. By comparing the calculated results with the air volume required by the tunnel, the optimal ventilation mode under different operating conditions is proposed, which can provide guidance for the ventilation decision of the tunnel operation.
【學位授予單位】：長安大學
【學位級別】：博士
【學位授予年份】：2015
【分類號】：U453.5
，
本文編號：2399921
[Abstract]:The highway tunnel ventilation system is a dynamic system. The change of ambient temperature, speed and traffic volume will cause the dynamic change of wind pressure and air volume in tunnel. In long and deep buried highway tunnels, high ground temperature is often encountered, which results in the variation of tunnel heat potential difference, which has an impact on ventilation system. The distribution characteristics of air flow temperature field in tunnel and vertical (oblique) well and the calculation method of heat potential difference in complex tunnel ventilation system are studied, and the heat potential difference and traffic wind pressure are used effectively to optimize the operation ventilation mode. It is very important to achieve the goal of saving energy and reducing consumption. In this paper, the unsteady heat transfer mechanism of surrounding rock and air flow at high ground temperature, the calculation method of thermal potential difference of multi-shaft tunnel and the wind temperature are studied by means of collecting data, theoretical analysis, numerical simulation and wind net calculation. The distribution characteristics of wind pressure and wind volume in the tunnel are analyzed reasonably when the speed and traffic volume change. The following research work is carried out: 1. The influencing factors of air flow temperature change in tunnel are analyzed, the unsteady heat transfer mechanism of surrounding rock and air flow is proved, the model of tunnel longitudinal surrounding rock and air flow unsteady state heat transfer is established, and the calculation formula of tunnel longitudinal air flow temperature is deduced. The model is used to calculate the longitudinal wind temperature distribution of a tunnel, and compared with the field test results, the reliability of the tunnel longitudinal surrounding rock and wind flow unsteady heat transfer model is verified. 2. The formula of air flow temperature change caused by air self-compression heat, surrounding rock heat transfer and water evaporation in tunnel air supply well is studied, and a mathematical model for calculating air flow temperature in air supply well and exhaust air well by using difference method is established. The mechanism of thermal potential difference caused by air flow temperature difference inside and outside the tunnel is analyzed. Based on the principle of ventilation calculation and the basic principle of connectors, it is proposed that the thermal potential difference is the wind pressure caused by the heavy difference of air column under the action of gravity field. The air column weight difference method is used to calculate the thermal potential difference in the tunnel. The calculation formula of the thermal potential difference is derived, and the wind pressure and air volume distribution characteristics of the longitudinal slope tunnel under the action of air column gravity are analyzed in combination with the finite volume method software Fluent. The reliability of the thermal potential difference calculation model based on the air column weight difference method is verified. 4. 4. The related grid model is established in fluent, and the influence of ambient temperature change on the combined ventilation of centralized ventilation and segmental ventilation in shaft is analyzed. The results show that there are different ambient temperatures and different ventilation modes in the tunnel. The distribution characteristics of air flow velocity, temperature and density in exhaust and air supply wells are analyzed, and the variation law of heat potential difference in different ventilation modes is analyzed in combination with the air column weight difference method. 5. A method of calculating air column bulk density combined with wind network solution is proposed to study the distribution characteristics of wind pressure in tunnel when heat potential difference and traffic wind pressure change. The wind flow balance law, wind pressure balance law and resistance law in tunnel ventilation network are analyzed. The resistance model and dynamic model of tunnel wind network are established, including ventilation resistance calculation model, fan wind pressure calculation model, traffic wind pressure calculation model, natural wind pressure calculation model, fire wind pressure calculation model and shaft ventilation calculation model. The node method is taken as the basic algorithm, the linear iterative calculation method is adopted, and the program of tunnel ventilation network calculation based on temperature effect is written by Visual C language. 6. Based on the Qinling Zhongnanshan Highway Tunnel Project, the distribution characteristics of air pressure in tunnel, exhaust well and air supply well under different ambient temperature, different speed and different traffic volume are analyzed by using ventilation network calculation program. By comparing the calculated results with the air volume required by the tunnel, the optimal ventilation mode under different operating conditions is proposed, which can provide guidance for the ventilation decision of the tunnel operation.
【學位授予單位】：長安大學
【學位級別】：博士
【學位授予年份】：2015
【分類號】：U453.5
，
本文編號：2399921
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