壁面熱通量 的英文怎麼說
中文拼音 [bìmiànrètōngliáng]
壁面熱通量
英文
wall heat flux-
The article takes a 600mw natural cycle drum boiler ( soot blow using steam ) as investigating object, establishes soot accumulation loss and soot blowing energy loss models for its water cooling wall, superheater, economizer and air preheater respectively, set up instructions for soot blower operating. simulating calculation results are compared with site data to verify usefulness of key models. the article introduced the operation optimizing design of soot blowers of yanzhou no2 power plant based on theoretical research
本文以600mw汽包自然循環鍋爐（蒸汽吹灰）為具體分析對象，分別建立其水冷壁、過熱器、省煤器、空預器的積灰損失和各受熱面吹灰能量損失的模型，建立相應的吹灰器運行規則指導，對設計中的關鍵模型問題，通過模擬計算及與現場數據作比較的方法，驗證其可用程度。Based on the review, the fluid flow and heat transfer in the curved circular and rectangular pipes have been researched by employing perturbation method and numerical simulation with a physical model under the rotational orthogonal curvilinear coordinate in a rotating curvilinear pipe with multi - parameters. we firstly analyzed the fully developed fluid flow and heat transfer, mixed convection heat transfer, the development of flow and heat transfer in the inlet in different cross section ( circular, elliptical, annular and rectangular crossection ). the variations of the secondary flow, axial velocity, distribution of temperature, the friction force on the wall, the ratio of friction factor as well as the nusselt number with different dimensionless parameters had been examined in detailed
本文在總結和分析了一個世紀以來有關曲線管道流動和換熱特性的研究成果的基礎上，以旋轉正交曲線坐標系統下的多參數旋轉螺旋管道中的對流傳熱為物理模型，通過攝動方法和有限體積法，首次對各種截面（圓截面、橢圓截面、環形截面、矩形截面）旋轉曲線管道內充分發展流動的流動結構和傳熱特性（包括耦合對流傳熱特性）以及旋轉曲線管道開口段發展流動的流動結構和換熱特性進行了系統的數值模擬和理論分析，詳細討論了各種無量綱參數對管道內軸向速度分佈、二次流結構、溫度分佈、壁面摩擦力、摩擦系數比以及管道nusselt數的影響，獲得了若干創新性成果。This text completely and systematically studies the status and the development of the pyrolysis and the fluidization of biomass, which distill the bio - oil in the domestic and international area, as well as the existing problems. this thesis primarily include following aspects : ( l ), by experimenting and measuring the energy ( heat value ) and the content of c, h, n chemical element of right 20 kinds of common biomass, on the base of the experimental result, and respectively established the biomass energy predict experiment formula with the element of h and c is from change, and passed the ro. os examination, which provides the basis and convenience for flash pyrolysis fluidization device energy to convert the rate to compute with biomass energy utilization calculation ; ( 2 ), proceeded the tg and dtg experimentation equal velocity ( 10 ? / min, 20 ? / min, 40 ? / min, 60 ? / min ) heating and constant temperature heating by studying on eight kinds of biomass samples, according to the experimental data and arrhenius formula, we established the dynamics model of pyrolysis of, then, using the goast - redfern and p function, we also solved the dynamics parameters and analyze out every kind of biomass ' s frequency factor and parameters of activation energy, and established the every kind of dynamics model of pyrolysis of biomass, all of these provide the theories and basis to make sure the reactor ' s flash pyrolysis work temperature scope design and the describing of pyrolysis reactor dynamics ; ( 3 ), in order to study and ascertain the process of heat completely getting to pyrolysis time of varied size biomass particles, we observed and measured the ratio of length and diameter ( l / d ) with the varied biomass through electron microscope, we concluded the l / d ratios usually is from 5. 0 to 6. 0, the average is 5. 3 ; ( 4 ), we studied the process of biomass transiting and the theory of complete pyrolysis time with the theory of complicated heat field, we got the time ( t ) of the varied size biomass particles arriving to complete pyrolysis, and we knew that the complete pyrolysis time and the time which get to the biggest production ratio are identical, all of these studies provide the theory base for design and forecasting the flash pyrolysis reactor solid state resort time ; ( 5 ), according to the above experiment result, synthesize to make use of the engineering the mechanics, engineering the material, machine the design to learn the principle, deduce, establish the theory of rotation cone flash pyrolysis reactor material resort time ( t ) and reasonable rotation velocity ( or frequency ) relation theory ; and ( 6 ), we gave the reactor ' s smallest cone angle certain, reactor cone wall strength design theory, the reactor production ability theory, the power design method and the critical rotation velocity theory
本文較全面、系統地綜述了國內外生物質熱解液化制取生物燃油技術研究發展現狀及存在的問題，主要研究內容有： （ 1 ）實驗、測定了20種常見生物質的能量（發熱量）和c 、 h 、 n元素含量，根據實驗結果分別建立了以h和c為自變量的生物質能量預測經驗公式，並通過r _ （ 0 . 05 ）檢驗；為閃速熱解液化裝置能量轉化率計算和生物質能量利用率計算提供了依據和方便； （ 2 ）選擇了8種生物質試樣作了等加熱速率（ 10 min 、 20 min 、 40 min 、 60 min ）和恆溫加熱的tg和dtg實驗，根據實驗數據和阿倫尼烏斯公式建立了生物質熱解反應動力學微分方程，並採用goast - redfem積分法和p函數對其動力學參數進行了求解，解析出各種生物質的頻率因子和活化能參數，進而建立了各種生物質的熱解動力學模型，為科學確定反應器的閃速熱解工作溫度范圍及熱解反應動力學描述，提供了理論和依據； （ 3 ）為研究和確定不同尺度的生物質顆粒中心達到全熱解的時間，在體視顯微鏡下對不同粒度的生物質顆粒的長徑比進行了實驗觀察和測定，得出生物質的長徑比（ l d ）一般在5 . 0 6 . 0之間，平均為5 . 3的結果； （ 4 ）採用復雜溫度場傳熱學理論對生物質傳熱過程及充分熱解時間理論進行了研究，解析推導出了不同尺寸生物質顆粒中心溫度達到充分熱解溫度的時間（ t ） ，得出了理論推導的充分熱解時間與最大產油率的熱解時間相一致的結果，為閃速熱解反應器固相滯留時間設計和預測提供了理論依據； （ 5 ）根據上述實驗結果，綜合運用工程力學、工程材料、機械設計學原理，推導、建立了轉錐式閃速熱解反應器物料滯留時間（ ）與轉速（或頻率）合理匹配理論； （ 6 ）提出了轉錐式閃速熱解反應器的最小錐角設計、錐壁強度設計、生產能力設計理論和功率計算方法及臨界轉速理論等。When in experiment, the air was heated by the film heater installed on the above and below surface of channel, adopting various air velocity of flow, test import ' s and export ' s temperature, wall temperature, fluid flux and the drop of pressure, and the other parameter. adopting nu and nu0 to analyze the baffle ' s situation of heat transfer and fluid flow, which baffle was holed various diameters
實驗時，通過矩形通道上下壁面敷設的電加熱膜加熱通道空氣，改變空氣流速，測試不同工況時的進出口溫度、壁面溫度、流體流量和壓力損失等參數，並採用無量綱努謝爾特準則數nu 、 nu _ 0等分析了設置不同開孔折流板的換熱與流動情況。Abstract : the in servie tubular heaters built early in refineries and chemical plans have low thermal load and low heat efficiency, therefore measures for technical reform are offered, including ( 1 ) enlarging the surface area of convection tubes to increase the thermal load of rhe convection section ; ( 2 ) increasign the heat interchanging area of radiant tubes ; ( 3 ) changing the height of the chimney ; ( 4 ) using new burner with forced air supply to increase calorific capacityu ; ( 5 ) adding air preheater between the convection section and chimney to enhence the temperature of the air entering the furnace ; ( 6 ) adopting high temperature radiant coating to improve the effect of radiant heat interchanging
文摘:針對早期建造的煉油廠和化工廠在役管式加熱爐熱負荷和熱效率低的狀況，提出了若干技術改造措施包括，增大對流管表面積以增大對流段的熱負荷；增加輻射管的換熱面積；修正煙囪高度；換用新型燃燒器，變自然通風為強制供風，以增大燃燒器的發熱量，減小過剩空氣系數，節省燃料2 % 3 % ；在對流段和煙囪之間增設空氣預熱器以提高空氣入爐溫度；採用高溫輻射塗料增強輻射換熱效果，從而增加熱源對爐壁的輻射傳熱量和爐管的傳熱量等。The in servie tubular heaters built early in refineries and chemical plans have low thermal load and low heat efficiency, therefore measures for technical reform are offered, including ( 1 ) enlarging the surface area of convection tubes to increase the thermal load of rhe convection section ; ( 2 ) increasign the heat interchanging area of radiant tubes ; ( 3 ) changing the height of the chimney ; ( 4 ) using new burner with forced air supply to increase calorific capacityu ; ( 5 ) adding air preheater between the convection section and chimney to enhence the temperature of the air entering the furnace ; ( 6 ) adopting high temperature radiant coating to improve the effect of radiant heat interchanging
針對早期建造的煉油廠和化工廠在役管式加熱爐熱負荷和熱效率低的狀況，提出了若干技術改造措施包括，增大對流管表面積以增大對流段的熱負荷；增加輻射管的換熱面積；修正煙囪高度；換用新型燃燒器，變自然通風為強制供風，以增大燃燒器的發熱量，減小過剩空氣系數，節省燃料2 % 3 % ；在對流段和煙囪之間增設空氣預熱器以提高空氣入爐溫度；採用高溫輻射塗料增強輻射換熱效果，從而增加熱源對爐壁的輻射傳熱量和爐管的傳熱量等。In fluent, the flow field of the tube wall, center, top, middle and bottom of the evacuated solar collector tube can be observed, the temperature - time curve and radial temperature gradient can be obtained, the heat loss of different part can be directly captured. 3. all kinds of effect factors of the flow field and temperature field have been analyzed
通過fluent計算，清楚地觀察到太陽能真空集熱管壁面和中心部分，頂部、中部和底部在各種工況下的流場分佈均不相同；得出了各種工況下的溫度-時間變化曲線，沿軸線方向的溫度梯度；同時還計算了各部分熱損的傳熱流量； 3The channel scale on transpiration cooling for the platelet thrust chamber of liquid propellant rocket engine is approaching micron dimension. it is very possible that micro - scale effects will occur in the flow and heat transfer of the channel. in the past, researchs on flow and heat transfer in the platelet micro - channel are mostly based on macro - scale theory
液體火箭發動機推力室壁面發汗冷卻通道的尺度已達微米量級，通道內的流動與換熱很可能存在微尺度效應，以前的相關研究都以宏觀尺度的理論為依據，其研究結果的合理性需要進行微尺度效應的分析。In order to study the regeneration mechanism of dpf in detail, we still need a mathematical model of the channel unit, which present temperature field and the soot reaction rate of the channel. finally, it points out the influences of various factors to the regeneration process by computing the numerical solution of model under different boundary conditions and geometry parameters, such as the initial temperature, the gas flow rate, the oxygen concentration, the sediment quantity and the wall thickness of the filters, and so on. in this way, the paper provides theoretical guidance for optimization design of the dpf
首先研究了干凈壁流式過濾體的加熱特性，然後在加熱和燃燒理論的基礎上建立了微粒捕集器再生過程的數學模型，並對模型進行了數值計算，得到了捕集器內部的三維溫度場分佈以及溫度梯度分佈，結果與實驗值吻合較好，驗證了模型的正確性;為了詳細的研究微粒捕集器的再生機理，建立了孔道單元數學模型，得到了孔道內的溫度場分佈和微粒反應速率分佈;最後，通過求解模型在不同邊界條件和不同幾何參數下的數值解，分析了各種因素對再生過程的影響，如過濾體初始溫度、過濾體內氣流的流動速率、氧濃度、微粒沉積量以及過濾體壁面厚度，為微粒捕集器的優化設計提供理論指導。分享友人