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英文原文 1 =( is of of h = h( ) is m = m ( ) is p = p( ), in Q = Q( ), V = V ( ) of In in of o i lo i u cs u ,.+= (l, g ,. += (l, l m of or of of he to to in of is by u = in of be in .2 as as it of as of as as it e is is as as on of to is by of As 52 3 in is a of of as as on of is to in is is no or it is in is by of by to is by of is in of to is at a If in is in if is be in of a is to in to is by . is is In dV/d be If or is of be in In of in is is is of is by a .( oi ,. ( 53 .,.(of m . (wm/s = ( ) is m in of , = m/V . he is it be as a of of . is su s in,su c( at of 0 of of is at so = 0, if is se s in,di s(e of c of 0 of (2 12 ( is of in a if 54 3 in a to a of an by or of of of it is to of to to a to a of of is In to is is to be at at a if is in of as in No is to of a of be by an of An is to a of is by m . (r w of g lg g or = (in a by to of be “ in it it is 55 02211 l(f(is is on Dg is of 2 g dx is to in of be in of at to at of to ( = g + g in f be as a of a is of to in of be in of to At in of a It is as an of to at . il of or or in a a of be to of as or in or be if to A be A to is is to be be 21. (is in as an 6 3 n to a is to To is a of by of is is by or by of be in of a of of be it or by in a of in of In a is in is an a a be in of a o = o is , dS is of ho is on an of of or by is o of of be o 00 (ho is N (of in at 1 ,(o,p is at k is of k = / t = / , = of o o o is to of is to of 57 is on is it or or is is by of to a by an to on of of in of 0 0m/s, is 0 m. et 1992. of a of be on of to be a of is of dS n an of is o i lo i i m 11 ( is is or of in be by of o m c 111(If k , or In of a is be be as a of be by as a of as is of p = ,V ) u = ,V ) be of 中文译文 维数学模型 51 内部能量守恒 =(其中 是角度的旋转的主旋翼 h =h( )的比焓, m =m ( )是质量流率 p = ( ) ,工作腔的控制体积中的流体压力, Q = Q( )的流体之间的热传递和压缩机周围, V = V ( ) ,压缩机工作腔中的本地卷。 在上述方程中,输入和输出的下标表示的流体流入及流出。 流体的总焓流入由以下组件: o i lo i u cs u ,. (其中,下标 L, G 表示泄漏增益 抽吸条件,和油为石油。 流体总流出焓包括: t ,. (指数升, l 表示泄漏损耗和 示放电条件与 m显示表示放电注入的油或其它液体污染的气体的质量流率 右手 法 侧的能量方程由模型的下列术语 流体和压缩机的螺杆转子和壳体,并通过它们的周边,由于气体的温度 的 差异, 上 述壳体和转子的表面之间的热交换的传热系数求值表达式 = 通过主转子的外径和内径之间的差异为特征长度的雷诺数和努塞尔数 。这可能不是用于此目的的最合适的尺寸,但出现的特征长度在 指数部分的传热系数的表达式,因此,只要它表征压缩机的体积 , 它仍然在同一个数量级,作为其他特征尺寸的影响不大的机器。特征速度为 的计算从本机的质量流量和横截面面积。这里的表面,在其上进行热交换,以及壁温,依靠的主旋翼的旋转角度 。 上述 所表示的商品的大量摄入量和其平均焓由于工作体积的气体流入的能量增益 决定 。因此,能量的流入的旋转角变化。在吸入期间, 等于 气体进入工作容积带来的平均气体焓 。 52 3 螺杆压缩机性能的计算吸入室中占主导地位。 然而 ,在吸入口关闭时,一定量的压缩气体通过间隙泄漏到压缩机工作腔 。该气体的质量,以及其焓 在 气体泄漏方程的基础上确定。工作体积充满了气体,由于泄漏,只有当工作体积周围的空间中的气体压力较高,否则无泄漏,或它是在相反的方向,即从对其他压力通风系统的工作腔。 总流入焓进一步校正的焓的量带入工作腔注入的油。 由于从工作体积的气体流出的能量损失是指由商品质量的流出和平均气体焓。在 工作过程中,这是进入排放气室,被压缩的气体的同时,在扩展的情况下,由于不适当的排出压力,这是通过在较低压力下工作体积到邻近的空间的间隙泄漏的气 体。如果工作腔中的压力低于在排出室,排放口是打开的,该流程将在相反的方向,即从排出气室进入工作腔。质量的变化,有一个负号 其假定的焓等于压力腔中的平均气体焓。 供给的工作气体在压缩过程中的热力学表示由术语 这个术语是从本地的压力和体积变化率进行评估。后者被定义产生瞬时工作体积和其旋转角度的变化的螺杆运动学的关系得到的。事实上,术语的 差 ,捕获和重叠区域校正。 如果油或其它流体注入 上 述压缩机的工作腔,油质量的流入和其焓应包括在流入条款 而 事实,尽管 在混合物中的油的质量分数显着的体积流率时,其效果是 不明显的 ,因为油的体积分数通常是非常小的。总流出的流体的质量,还包括注入的油,其中的较大部分仍然与工作流体混合。气体之间的热传递和油滴描述由一个一阶微分方程 确定 。 质量连续性方程 o u to u (质量连续性方程 o u ,(维数学模型 53 质量的流出率包括: (质量流率的每一个 方程 满足连续性方程 . (其中 W m/s表示流体速度, - 流体
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