【摘要】：電池?zé)峁芾硐到y(tǒng)對于新能源汽車動力性能有著至關(guān)重要的影響,有效的冷卻能夠改善動力電池工作環(huán)境和工作性能,從而保證電動汽車的行車安全性和可靠性。國內(nèi)外研究者在動力電池冷卻技術(shù)及電池?zé)峁芾矸矫骈_展了大量研究,主要針對空冷、水冷、相變材料冷卻和熱管冷卻這幾種冷卻技術(shù)進(jìn)行研究和改善,目前工程實(shí)際普遍使用的是空冷和水冷系統(tǒng),但由于相變冷卻對于提升電池組溫度一致性具有很大優(yōu)勢,電池組相變材料冷卻和熱管冷卻有望發(fā)展為新一代電池組熱管理技術(shù)。本文依托國家自然基金項(xiàng)目(項(xiàng)目號:51375202),采用理論研究、仿真分析和試驗(yàn)驗(yàn)證相結(jié)合的研究方法,建立了車用鋰離子電池的電化學(xué)-熱耦合模型,對熱管冷卻系統(tǒng)的基礎(chǔ)傳熱問題進(jìn)行了研究,并通過仿真和試驗(yàn)研究了熱管冷卻系統(tǒng)冷卻特性和溫度場均勻性問題,通過研究基礎(chǔ)共性技術(shù),為熱管冷卻系統(tǒng)應(yīng)用于新能源汽車動力電池?zé)峁芾硐到y(tǒng)奠定基礎(chǔ)。本文主要研究內(nèi)容如下:(1)建立了鋰離子電池的電化學(xué)-熱耦合模型,搭建了數(shù)學(xué)模型控制方程,研究了電池的基本特性,包括電池容量、電池充放電曲線、不同倍率下的放電曲線及單體電池的溫度特性。(2)主要針對熱管冷卻系統(tǒng)涉及到的基礎(chǔ)傳熱問題進(jìn)行了研究,包括熱管相變傳熱、流體橫掠管束的外部強(qiáng)迫對流傳熱系數(shù)和多層固體熱傳導(dǎo)中的接觸熱阻。介紹了熱管冷卻系統(tǒng)的結(jié)構(gòu)與機(jī)理,將復(fù)雜的熱管內(nèi)伴隨相變傳熱的兩相流動問題進(jìn)行了簡化,得到了熱管相變傳熱的等效傳導(dǎo)模型;通過試驗(yàn)關(guān)聯(lián)式求解了流體橫掠管束的外部強(qiáng)迫對流傳熱系數(shù);利用功率譜法確定了粗糙接觸表面的分形參數(shù),并通過Monte Carlo隨機(jī)數(shù)模擬方法描述了粗糙接觸表面形貌,最終基于建立的粗糙表面形貌確定了接觸熱導(dǎo)。(3)基于COMSOL仿真軟件,建立了以12塊動力電池為基礎(chǔ)的熱管冷卻系統(tǒng)仿真模型,研究了單體電池的溫升特性,并著重研究了電池模組的溫度場均勻性以及溫度均勻性的影響因素,此外,對比研究了熱管冷卻系統(tǒng)相對于自然對流的溫升特性、高溫冷卻特性和低溫加熱特性。(4)搭建了動力電池組熱管冷卻試驗(yàn)系統(tǒng),通過對自然對流冷卻和熱管-強(qiáng)制空氣冷卻的對比試驗(yàn)研究,分析動力電池組在不同冷卻方式、不同放電倍率下的冷卻效果和溫度場均勻性,針對仿真與試驗(yàn)結(jié)果對熱管冷卻系統(tǒng)進(jìn)行了對比分析,為熱管冷卻系統(tǒng)應(yīng)用于新能源汽車動力電池?zé)峁芾硐到y(tǒng)奠定了一定的基礎(chǔ)。
[Abstract]:Battery thermal management system plays an important role in the power performance of new energy vehicles. Effective cooling can improve the working environment and performance of power batteries, so as to ensure the safety and reliability of electric vehicles. Researchers at home and abroad have carried out a lot of research on power battery cooling technology and battery thermal management, mainly on air cooling, water cooling, phase change material cooling and heat pipe cooling. At present, air cooling and water cooling systems are widely used in engineering practice, but phase change cooling has great advantages in improving the temperature consistency of battery pack. Battery pack phase change material cooling and heat pipe cooling are expected to develop into a new generation of battery thermal management technology. In this paper, based on the National Nature Fund project (project number: 51375202), the electrochemical-thermal coupling model of lithium-ion battery for vehicle is established by using the research method of theoretical research, simulation analysis and experimental verification. The basic heat transfer problem of the heat pipe cooling system is studied, and the cooling characteristics and temperature field uniformity of the heat pipe cooling system are studied through simulation and experiment, and the basic common technology is studied. It lays a foundation for the application of heat pipe cooling system in the thermal management system of power battery of new energy vehicle. The main contents of this paper are as follows: (1) the electrochemical-thermal coupling model of lithium-ion battery is established, the mathematical model control equation is set up, and the basic characteristics of the battery are studied, including battery capacity, battery charge-discharge curve, discharge curve under different rate and temperature characteristics of single cell. (2) the basic heat transfer problems involved in heat pipe cooling system are studied, including phase change heat transfer of heat pipe. The external forced convective heat transfer coefficient of the fluid traversing the tube bundles and the contact thermal resistance in the multi-layer solid heat conduction. The structure and mechanism of the cooling system of the heat pipe are introduced, the complex two-phase flow problem accompanied by the phase change heat transfer in the heat pipe is simplified, and the equivalent conduction model of the phase change heat transfer of the heat pipe is obtained, and the external forced convective heat transfer coefficient of the fluid traversing the tube bundles is solved by the experimental correlation. The fractal parameters of rough contact surface are determined by power spectrum method, and the rough contact surface morphology is described by Monte Carlo random number simulation method. Finally, the contact thermal conductivity is determined based on the established rough surface morphology. (3) based on COMSOL simulation software, the simulation model of heat pipe cooling system based on 12 power batteries is established, and the temperature rise characteristics of single cell are studied. The temperature field uniformity and the influencing factors of the temperature uniformity of the battery module are studied emphatically. in addition, the temperature rise characteristics, high temperature cooling characteristics and low temperature heating characteristics of the heat pipe cooling system relative to the natural convection are compared and studied. (4) the heat pipe cooling test system of the power battery pack is built, and the natural convective cooling and the heat pipe forced air cooling are compared and studied. The cooling effect and temperature field uniformity of power battery pack under different cooling modes and different discharge rates are analyzed. According to the simulation and test results, the cooling system of heat pipe is compared and analyzed, which lays a certain foundation for the application of heat pipe cooling system in the thermal management system of power battery of new energy vehicle.
【學(xué)位授予單位】：吉林大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2016
【分類號】：U469.72

【引證文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前2條

1 張凱鵬;電池成組液流熱控及其強(qiáng)化增效實(shí)驗(yàn)分析[D];吉林大學(xué);2017年

2 劉瑋;液冷式電池?zé)峁芾硐到y(tǒng)換熱特性與控制方法研究[D];吉林大學(xué);2017年

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本文編號：2505408