农业工程学报
農業工程學報
농업공정학보
2014年
16期
221-229
,共9页
孟广双%高德东%王珊%辛元庆%郑浩峻
孟廣雙%高德東%王珊%辛元慶%鄭浩峻
맹엄쌍%고덕동%왕산%신원경%정호준
灰尘%颗粒%范德华力%高海拔荒漠地区%电池板%受力参数%重力
灰塵%顆粒%範德華力%高海拔荒漠地區%電池闆%受力參數%重力
회진%과립%범덕화력%고해발황막지구%전지판%수력삼수%중력
dust%particle%van der Waals forces%high altitude desert area%solar panel%force parameters%gravity
高海拔荒漠地区电池板表面积灰严重制约着光伏发电效率和光伏组件寿命。该文在分析表面能的基础上,假设接触不变形条件下,依据宏观分子间作用理论分析提出了电池板表面灰尘颗粒粘附受力模型。结合青海共和地区电池板表面灰尘主要成分和粒径组成,给出了灰尘受力参数;计算了灰尘颗粒所受的范德华力、静电力及重力,给出由参数改变引起的灰尘受力的变化规律。结果表明:当灰尘颗粒半径较小时,颗粒与电池板间的主要粘附力为范德华力,当灰尘颗粒半径较大时,重力分量则成为主导粘附力,粘附合力取值范围为10-10~10-8 N;Lifshitz常数和分子间平均间距主要影响的是范德华力;灰尘颗粒总的静电力随灰尘颗粒半径的增大而增大,静电力的取值小于范德华力和重力分量。对灰尘粘附受力大小及其规律的研究,为高海拔荒漠地区光伏除尘提供理论依据。
高海拔荒漠地區電池闆錶麵積灰嚴重製約著光伏髮電效率和光伏組件壽命。該文在分析錶麵能的基礎上,假設接觸不變形條件下,依據宏觀分子間作用理論分析提齣瞭電池闆錶麵灰塵顆粒粘附受力模型。結閤青海共和地區電池闆錶麵灰塵主要成分和粒徑組成,給齣瞭灰塵受力參數;計算瞭灰塵顆粒所受的範德華力、靜電力及重力,給齣由參數改變引起的灰塵受力的變化規律。結果錶明:噹灰塵顆粒半徑較小時,顆粒與電池闆間的主要粘附力為範德華力,噹灰塵顆粒半徑較大時,重力分量則成為主導粘附力,粘附閤力取值範圍為10-10~10-8 N;Lifshitz常數和分子間平均間距主要影響的是範德華力;灰塵顆粒總的靜電力隨灰塵顆粒半徑的增大而增大,靜電力的取值小于範德華力和重力分量。對灰塵粘附受力大小及其規律的研究,為高海拔荒漠地區光伏除塵提供理論依據。
고해발황막지구전지판표면적회엄중제약착광복발전효솔화광복조건수명。해문재분석표면능적기출상,가설접촉불변형조건하,의거굉관분자간작용이론분석제출료전지판표면회진과립점부수력모형。결합청해공화지구전지판표면회진주요성분화립경조성,급출료회진수력삼수;계산료회진과립소수적범덕화력、정전력급중력,급출유삼수개변인기적회진수력적변화규률。결과표명:당회진과립반경교소시,과립여전지판간적주요점부력위범덕화력,당회진과립반경교대시,중력분량칙성위주도점부력,점부합력취치범위위10-10~10-8 N;Lifshitz상수화분자간평균간거주요영향적시범덕화력;회진과립총적정전력수회진과립반경적증대이증대,정전력적취치소우범덕화력화중력분량。대회진점부수력대소급기규률적연구,위고해발황막지구광복제진제공이론의거。
Along with the booming development of the photovoltaic industry, the later maintenance of photovoltaic power station and the improvement of photovoltaic power generation efficiency have gradually become the focus of attention. Under the condition of blown sand in high altitude desert areas, dust accumulation on the surface of solar panel has become one of the most significant factors which influences the consistency and efficiency of photovoltaic power station. The effects of dust deposition on photovoltaic conversion efficiency and dust removal methods were studied. The mechanism of dust particle adhesion was analyzed at first in this paper. Due to the surface free energy of the dust particle and solar panel, they interacted. The van der Waals force between spherical dust particles and the panel was derived from Lifshitz’s macro molecular interaction theory and the order of magnitudes van der Waals force was calculated. The electrostatic image force was simulated based on two known dust charge empirical expressions. The relationship between the radius of dust particle and the double layer electrostatic force was investigated by taking different values of the contact potential difference, which ranged from 0 to 0.5 V. Compared with the dust particle, the solar panel surface can be taken as an infinite disk. The relationship between the parameters and electric field force was obtained. Meanwhile, the gravity of dust particle was analyzed when the photovoltaic panels were mounted with an angle with respective to the horizontal plane. Through the analyses of all interactive forces, the conclusions that Van der Waals force of dust particle increased with increasing of the surface free energy were drawn. The dust particle radius ranged from 0.2×10-6 to 40×10-6 m, and the distance between molecules ranged from 10-9 to 10-7 m. Combined with Lifshitz constant (0.96-14.4 eV), the magnitude of dust van der Waals force was calculated as 10-10-10-9 N. The magnitudes of electrostatic image force and double layer electrostatic force were calculated as 10-13-10-12 N based on the charges (10-18-10-16 C) of dust surface and the contact potential difference (0-0.5 V). The radius of dust and the distance between molecules had smaller effects on the electrostatic image force and double layer electrostatic force than electrostatic image force. The dust particle radius R had no effects on the electric field strength. The electric field force increased with the increasing of R. The distance between molecules didn't affect the electric field force. The magnitude of electric field force was calculated as 0-10-13 N. The gravity of dust particle was affected by the radius and density of dust particle, and its magnitude was approximated as 10-10-10-9 N. The interactions between the dust particles were more complex, which was affected by the numbers of particles, the porous ratio, particle clearance and radius. Through analyzing all interactions between dust particle and solar panel surface, it is concluded that van der Waals force >gravity > electrostatic force when the dust radius was smaller (R<20×10-6 m), and gravity > van der Waals force >electrostatic force when the dust radius was larger (R>20×10-6 m). The adhesion force between the dust particle and solar panel surface increased with the increasing of dust radius, and its magnitude ranged from 10-10 to 10-8 N. In the dry and windy desert area, the combination of gravity and van der Waals force plays an important role without considering the chemical interactions.