【機械類畢業(yè)論文中英文對照文獻翻譯】包絡(luò)法的資產(chǎn)負債【word英文1611字6頁word中文翻譯2512字6頁】
【機械類畢業(yè)論文中英文對照文獻翻譯】包絡(luò)法的資產(chǎn)負債【word英文1611字6頁word中文翻譯2512字6頁】,機械類畢業(yè)論文中英文對照文獻翻譯,word英文1611字6頁,word中文翻譯2512字6頁,機械類,畢業(yè)論文,中英文,對照,對比,比照,文獻,翻譯,包絡(luò),資產(chǎn)負債,word,英文,中文翻譯
中文譯文
A
包絡(luò)法的資產(chǎn)負債
螺桿壓縮機轉(zhuǎn)子Stosic 1998年之后，被視為非平行不相交的螺旋齒輪，或在圖的交叉軸。 A.1。 X01， y01和x02之前，y02是該點的坐標的坐標系統(tǒng)中的固定的主轉(zhuǎn)子和閘轉(zhuǎn)子的端部轉(zhuǎn)子段，如示于圖。 1.3。 Σ是繞X軸的旋轉(zhuǎn)角度。的轉(zhuǎn)子軸的旋轉(zhuǎn)，在其軸承是天然的轉(zhuǎn)子運動。雖然主旋翼旋轉(zhuǎn)通過角度θ ，閘轉(zhuǎn)子的旋轉(zhuǎn)通過角度τ =r1w / rw θ = z2/z1θ ，其中rw和z是分別的轉(zhuǎn)子葉片的節(jié)距圓的半徑和數(shù)量。此外，我們定義外部和內(nèi)部的轉(zhuǎn)子半徑： r1e =r1w +r1和r1i=r1W –r0。轉(zhuǎn)子軸之間的距離是C =r1W + r2W 。 p是在給定的單元轉(zhuǎn)子旋轉(zhuǎn)角的轉(zhuǎn)子引線。標1和2分別涉及的主要和閘轉(zhuǎn)子。
圖。 A.1。坐標系與非平行交錯軸斜齒輪
與一個給定的，或產(chǎn)生表面R1 （T， θ ）的嚙合，或產(chǎn)生的表面以確定，該程序開始。一個集合中仍將產(chǎn)生表面參數(shù)形式：R2 （T， θ， τ） ，其中t是一個配置參數(shù)， θ和τ是運動參數(shù)。
包絡(luò)面r1和r2之間的嚙合方程，它決定：
r1 =r1(t, θ)=[ x1,y1,z1]
=x01cosθ-y01 sinθ, x01 sinθ+ y01 cosθ,p1θ] (A,.1)
= (A.2)
(A.3)
(A.4)
(A.5)
包絡(luò)方程，它決定了嚙合表面之間的r1和r2:
(A.6)
連同這些表面方程，完成方程系統(tǒng)。如果生成的表面1被定義的參數(shù)t ，系統(tǒng)可用于計算另一個參數(shù)θ ，現(xiàn)在t的函數(shù)，作為一個嚙合條件來定義一個生成的表面2，現(xiàn)在， t和θ的函數(shù)的。在包絡(luò)方程的交叉乘積表示的表面法線和?R ?τ2是兩個表面1和2 ，它們一起構(gòu)成了這兩個表面的接觸，共同的切點上的單點的相對滑動速度。由于平等到零的一個標量三重積下施加的坐標系，并是一個不變的屬性，因為相對速度，可以同時在兩個坐標系統(tǒng)的嚙合條件被定義為，以方便的形式表示：
（A.7）
插入前面的表達式到系統(tǒng)條件給：
(A.8)
這是適用于這里的條件交叉均勻鉛與非平行交錯軸斜齒輪的嚙合動作。的方法構(gòu)成的齒輪的生成過程，這是普遍適用的。它可用于合成的目的，這是有效地與平行軸的螺旋齒輪的螺桿壓縮機轉(zhuǎn)子。非平行和非相交軸越過轉(zhuǎn)子制造的形成工具的螺旋齒輪上具有均勻的引線，在滾齒的情況下，或與如銑削和磨削形成不含鉛。轉(zhuǎn)子檢查模板平面轉(zhuǎn)子滾刀一樣。在所有這些情況下，刀具軸不相交的轉(zhuǎn)子軸。
因此，注意到提出的包絡(luò)的方法的應用程序，以產(chǎn)生交叉的螺旋齒輪的嚙合條件。螺桿轉(zhuǎn)子齒輪，然后給出作為其使用一個基本例子的，而形成滾齒機工具的過程作為一個復雜的情況下給出。
軸角Σ ，中心距C ，和單元信息的兩個交叉的螺旋齒輪， p1和p2是相互依賴的。交錯軸斜齒輪嚙合仍保存著兩個齒條正截面具有相同的配置文件，并在機架上的螺旋角與軸角Σ= ψr1 + ψr2 。這是通過在x方向上的齒條迫使他們相應地調(diào)整到適當?shù)臋C架螺旋角的隱式移位。這當然也包括特殊情況下，這樣的齒輪可以是定向的，使得在軸角的齒輪的螺旋角的總和是等于： Σ = ψ1+ ψ2 。此外，中心距離可以等于齒輪節(jié)距半徑的總和：
成對的交叉斜齒輪可以與兩個螺旋角相同的符號或每個符號相反，左或右旋的，取決于其鉛和軸角Σ上的組合。
嚙合條件，可以解決只能通過數(shù)值方法。對于給定的參數(shù)t ，坐標X01 ， Y01和它們的衍生物?所述?X01和?Y01是已知的。甲猜到參數(shù)θ的值，然后用于計算X1，Y1 ，?T?所述?t1和? ? ?T1。經(jīng)修訂的θ值，然后推導和過程反復進行，直到連續(xù)兩個值之間的差異變得足夠小。
對于給定的橫向坐標和齒輪1的檔案中的衍生物，θ可以用來計算X1，Y1，和z1坐標其螺旋表面。齒輪2的螺旋面的表面，然后可以被計算出來。坐標z2的然后，可以使用計算τ和最后，其橫向的更新點坐標X2,Y2,可以得到的。
從這樣的分析，可以發(fā)現(xiàn)多宗個案。
(i) 當Σ = 0 ，方程滿足螺桿機轉(zhuǎn)子和也具有平行軸的螺旋齒輪的嚙合狀態(tài)。對于這樣的情況下，齒輪的螺旋角的有相同的值，但符號相反的齒比i = P2/P1為負。也可以應用相同的方程的根憂思從齒輪形成的齒條。此外，它描述所形成的平面爐灶，前銑削刀具和模板控制儀器。
(ii) 如果光盤銑削或研磨工具被認為形成的，它是足夠放置p2的= 0 。這是一個單一的情況下，工具自由轉(zhuǎn)動時，不影響嚙合過程。因此，反向變換不能直接獲得。
(iii) 全部范圍的嚙合條件是必需生成形成滾齒機工具的檔案。因此，這是最復雜的性態(tài)類型的齒輪，它可以從它產(chǎn)生。
B
雷諾運輸定理
繼Hanjalic ，1983年，雷諾運輸定理定義變量φ在有限的面積A的哪個矢量本地法線是dA和行進速度v在當?shù)卦摽刂屏靠赡艿目刂企w積V的變化，但不一定需要配合工程或材料物理系統(tǒng)。卷內(nèi)的時間的變量φ的變化率是：
(B.1)
因此，可以得出結(jié)論，變量φ的變化所造成的在體積V ：
- 變化的特定的變量φ = Φ / m的時間內(nèi)的體積，因為卷中的源（和匯）dV這是所謂的局部變化.
- 一種空間在它的變量φ和離開它的舊的空間，引起的變化在時間上的φρφv.dA稱為對流變化。
可表示的第一個貢獻可以所表示的體積積分：
(B.2)
而第二個貢獻可以表示由一個曲面積分：
(B.3)
因此：
( B.4)
這是雷諾運輸定理的數(shù)學表示。應用的材料系統(tǒng)內(nèi)控制音量Vm具有表面Am和速度v ，這是相同的流體速度w ，雷諾運輸定理讀?。?
(B.5)
如果該控制量選擇在一個瞬間，以配合控制體積V的體積積分是相同的為V和Vm和曲面積分是相同的，對于A和Am ，然而，這些積分的時間導數(shù)是不同的，因為在接下來的時間間隔，控制體積不相符。但是，是一個術(shù)語，它的兩個時間間隔是相同的：
(B.6)
如果被固定的坐標系中的控制量，即，如果它不移動時，v = 0 ，因此：
(B.7)
或:
(B.8)
如果被固定的坐標系中的控制量，即，如果它不移動，v = 0和結(jié)果：
(B.9)
因此：
(B.10)
最后，高斯定理的應用導致的常見形式：
(B.11)
如前所述，變量φ的變化所造成的來源q內(nèi)的體積V和以外的體積的影響。這些效應可能是正比于系統(tǒng)的質(zhì)量或體積的，或者它們可以在系統(tǒng)表面行事。
由下式給出的體積積分的第一個效果，和由下式給出的表面積分的第二個效果。
(B.12)
q可以是標量，矢量或張量。
組合的最后兩個方程給出：
或
(B.13)
省略不可分割的跡象給出：
(B.14)
這是眾所周知的守恒定律形式的變量。由于φ= 1 ，這將成為連續(xù)性方程：，最后卻是：
或
(B.15)
是變量φ的重大或衍生工具。這個等式特別守恒定律的推導是非常方便的。如前面提到的φ= 1導致的連續(xù)性方程，φ = u到動量方程， φ= e，其中e是比內(nèi)能，導致了能量方程， φ = s時，熵方程等。
如果的表面，其中的流體承載可變Φ進入或離開控制量，可以被識別，對流的變化可方便采寫：
(B.16)
其中over scores表示變量的平均入口/出口表面秒。這導致的守恒定律的宏觀形式：
(B.17)
其中規(guī)定詞： （ Φ ）= （流入Φ ） - （流出Φ ）+ （源的Φ的變化率）
英文原文
A
Envelope Method of Gearing
Following Stosic 1998, screw compressor rotors are treated here as helical gears with nonparallel and nonintersecting, or crossed axes as presented at Fig. A.1. x01, y01 and x02, y02are the point coordinates at the end rotor section in the coordinate systems fixed to the main and gate rotors, as is presented in Fig. 1.3. Σ is the rotation angle around the X axes. Rotation of the rotor shaft is the natural rotor movement in its bearings. While the main rotor rotates through angle θ, the gate rotor rotates through angle τ = r1w/r2wθ = z2/z1θ, where r w and z are the pitch circle radii and number of rotor lobes respectively. In addition we define external and internal rotor radii: r1e= r1w+ r1 and r1i= r1w? r0. The distance between the rotor axes is C = r1w+ r2w. p is the rotor lead given for unit rotor rotation angle. Indices 1 and 2 relate to the main and gate rotor respectively.
Fig. A.1. Coordinate system of helical gears with nonparallel and nonintersecting
Axes
The procedure starts with a given, or generating surface r1(t, θ) for which a meshing, or generated surface is to be determined. A family of such gener-ated surfaces is given in parametric form by: r2(t, θ, τ ), where t is a pro?le parameter while θ and τ are motion parameters.
r1 =r1(t, θ)=[ x1,y1,z1]
=x01cosθ-y01 sinθ, x01 sinθ+ y01 cosθ,p1θ] (A,.1)
= (A.2)
(A.3)
(A.4)
(A.5)
The envelope equation, which determines meshing between the surfaces r1 and r2:
(A.6)
together with equations for these surfaces, completes a system of equations. If a generating surface 1 is de?ned by the parameter t, the envelope may be used to calculate another parameter θ, now a function of t, as a meshing condition to define a generated surface 2, now the function of both t and θ. The cross product in the envelope equation represents a surface normal and ?r2 ?τ is the relative, sliding velocity of two single points on the surfaces 1 and 2 which together form the common tangential point of contact of these two surfaces. Since the equality to zero of a scalar triple product is an invariant property under the applied coordinate system and since the relative velocity may be concurrently represented in both coordinate systems, a convenient form of the meshing condition is de?ned as:
（A.7）
Insertion of previous expressions into the envelope condition gives:
(A.8)
This is applied here to derive the condition of meshing action for crossed helical gears of uniform lead with nonparallel and nonintersecting axes. The method constitutes a gear generation procedure which is generally applicable. It can be used for synthesis purposes of screw compressor rotors, which are electively helical gears with parallel axes. Formed tools for rotor manufacturing are crossed helical gears on non parallel and non intersecting axes with a uniform lead, as in the case of hobbing, or with no lead as in formed milling and grinding. Templates for rotor inspection are the same as planar rotor hobs. In all these cases the tool axes do not intersect the rotor axes.
Accordingly the notes present the application of the envelope method to produce a meshing condition for crossed helical gears. The screw rotor gearing is then given as an elementary example of its use while a procedure for forming a hobbing tool is given as a complex case.
The shaft angle Σ, centre distance C, and unit leads of two crossed helical gears, p1 and p2 are not interdependent. The meshing of crossed helical gears is still preserved: both gear racks have the same normal cross section pro?le, and the rack helix angles are related to the shaft angle as Σ = ψr1+ ψr2. This is achieved by the implicit shift of the gear racks in the x direction forcing them to adjust accordingly to the appropriate rack helix angles. This certainly includes special cases, like that of gears which may be orientated so that the shaft angle is equal to the sum of the gear helix angles: Σ = ψ1+ ψ2. Furthermore a centre distance may be equal to the sum of the gear pitch radii :C = r1+ r2.
Pairs of crossed helical gears may be with either both helix angles of the same sign or each of opposite sign, left or right handed, depending on the combination of their lead and shaft angle Σ.
The meshing condition can be solved only by numerical methods. For the given parameter t, the coordinates x01 and y01 and their derivatives ?x01?t and ?y01?t are known. A guessed value of parameter θ is then used to calculate x1, y1, ?x1 ?t and ?y1?t. A revised value of θ is then derived and the procedure repeated until the difference between two consecutive values becomes sufficiently small.
For given transverse coordinates and derivatives of gear 1 pro?le, θ can be used to calculate the x1, y1, and z1 coordinates of its helicoid surfaces. The gear 2 helicoid surfaces may then be calculated. Coordinate z2 can then be used to calculate τ and ?nally, its transverse pro?le point coordinates x2, y2 can be obtained.
A number of cases can be identi?ed from this analysis.
(i) When Σ = 0, the equation meets the meshing condition of screw machine rotors and also helical gears with parallel axes. For such a case, the gear helix angles have the same value, but opposite sign and the gear ratio i = p2/p1 is negative. The same equation may also be applied for the gen-eration of a rack formed from gears. Additionally it describes the formed planar hob, front milling tool and the template control instrument.122 A Envelope Method of Gearing
(ii) If a disc formed milling or grinding tool is considered, it is suffcient to place p2= 0. This is a singular case when tool free rotation does not affect the meshing process. Therefore, a reverse transformation cannot be obtained directly.
(iii) The full scope of the meshing condition is required for the generation of the pro?le of a formed hobbing tool. This is therefore the most compli-cated type of gear which can be generated from it.
B
Reynolds Transport Theorem
Following Hanjalic, 1983, Reynolds Transport Theorem de?nes a change of variable φ in a control volume V limited by area A of which vector the local normal is dA and which travels at local speed v. This control volume may, but need not necessarily coincide with an engineering or physical material system. The rate of change of variable φ in time within the volume is:
(B.1)
Therefore, it may be concluded that the change of variable φ in the volume V is caused by:
– change of the speci?c variable in time within the volume because of sources (and sinks) in the volume, dV which is called a local change and
– movement of the control volume which takes a new space with variable in it and leaves its old space, causing a change in time of for ρv.dA and which is called convective change
The ?rst contribution may be represented by a volume integral:.
(B.2)
while the second contribution may be represented by a surface integral:
(B.3)
Therefore:
( B.4)
which is a mathematical representation of Reynolds Transport Theorem.
Applied to a material system contained within the control volume V m which has surface A m and velocity v which is identical to the fluid velocity w, Reynolds Transport Theorem reads:
(B.5)
If that control volume is chosen at one instant to coincide with the control volume V , the volume integrals are identical for V and Vm and the surface integrals are identical for A and Am , however, the time derivatives of these integrals are different, because the control volumes will not coincide in the next time interval. However, there is a term which is identical for the both times intervals:
(B.6)
therefore,
(B.7)
or:
(B.8)
If the control volume is ?xed in the coordinate system, i.e. if it does not move, v = 0 and consequently:
(B.9)
therefore:
(B.10)
Finally application of Gauss theorem leads to the common form:
(B.11)
As stated before, a change of variable φ is caused by the sources q within the volume V and influences outside the volume. These effects may be proportional to the system mass or volume or they may act at the system surface.
The ?rst effect is given by a volume integral and the second effect is given by a surface integral.
(B.12)
q can be scalar, vector or tensor.
The combination of the two last equations gives:
Or:
(B.13)
Omitting integral signs gives:
(B.14)
This is the well known conservation law form of variable . Since for = 1, this becomes the continuity equation: ?nally it is:
Or:
(B.15)
is the material or substantial derivative of variable . This equation is very convenient for the derivation of particular conservation laws. As previously mentioned = 1 leads to the continuity equation, = u to the momentum equation, = e, where e is speci?c internal energy, leads to the energy equation, = s, to the entropy equation and so on.
If the surfaces, where the fluid carrying variable Φ enters or leaves the control volume, can be identi?ed, a convective change may conveniently be written:
(B.16)
where the over scores indicate the variable average at entry/exit surface sections. This leads to the macroscopic form of the conservation law:
(B.17)
which states in words: (rate of change of Φ) = (inflow Φ) ? (outflow Φ) +(source of Φ)
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