機(jī)械外文翻譯--被困-容積泵的設(shè)計(jì)-其他專業(yè)-資料下載頁
2025-01-19 06:13本頁面
【導(dǎo)讀】兩份重要文獻(xiàn)中的一份是的成果。在這項(xiàng)成果中，因?yàn)樯婕暗阶饔迷谛?。轉(zhuǎn)斜盤上的控制扭矩，作者考慮了柱塞泵油液密封的影響。這項(xiàng)工作只是在數(shù)值上。指出其中的優(yōu)勢(shì)。他在分析后得到這樣的結(jié)論，被困容積設(shè)計(jì)比標(biāo)準(zhǔn)設(shè)計(jì)更有效。此外，為了證實(shí)本文一般性的結(jié)論，這里對(duì)標(biāo)準(zhǔn)泵設(shè)計(jì)和被困泵設(shè)計(jì)的相對(duì)應(yīng)。在被困體積的情況下，在最底線部位能量由于柱塞腔體積自身的機(jī)械。容積體積的改變而被自動(dòng)的吸收。在這個(gè)位置，壓力的轉(zhuǎn)變由柱塞腔內(nèi)受控體積的壓。在這項(xiàng)研究中，因涉及到流體壓縮損失而檢驗(yàn)軸向柱塞泵的容積效率。這項(xiàng)報(bào)告把帶有插槽的標(biāo)準(zhǔn)配流盤形式和同時(shí)去除兩個(gè)插槽的被困容積。槽進(jìn)入柱塞腔內(nèi)直到柱塞腔內(nèi)的壓力等于柱塞泵排油區(qū)的壓力。事實(shí)上考慮了柱塞泵中單一個(gè)柱塞腔的四個(gè)不同的區(qū)域的壓力和流動(dòng)分析。圖1是修飾后的配流盤的圖解，它省去了最頂點(diǎn)和最底點(diǎn)的卸荷槽。
【正文】 tween intake pressure and discharge pressure. The intake flow results from the uncontrolled pression of the fluid through the slot. Within Regions 1 and 3, the pressure is approximated as a constant, either Pd or Pi , and the volumetric flow rate is given by the negative of the volumetric time rateofchange of the piston chamber itself, 2V˙ n5Apr tan(a)v cos(un). In Regions 2 and 4, the pressure and flow are changing as a function of u n and therefore a certain amount of analysis is required to approximate the pressure and flow characteristics within these regions. When the piston is located near u n5p/2, it can be shown for the standard pump design that the volumetric time rateofchange for the piston chamber is near zero. This means that the governing pressureriserate equation in this region can be approximated by （ 6） where Vt is the fluid volume in the piston chamber when u n 5p/2. Using the general form of Eq. ~3!, the flow out of the piston chamber may be modeled as （ 7） where . Recall that the discharge area, At , is a constant for this valveplate design. Substituting Eq. ~7! into Eq. ~6!, and recognizing that dt5(1/v)du n , the following separable differentialequation with the appropriate bounds of integration may be written: （ 8） where . Solving Eq. ~8! yields the following result for the pressure within the nth piston chamber as it moves across the valveplate slot near topdeadcenter within Region 2: （ 9） Substituting this result back into Eq. ~7! yields the following result for the discharge flow out of the piston chamber: （ 10） Note: these results are only valid near topdeadcenter when the piston chamber is connected to the valveplate slot. To insure that the valveplate slot is designed sufficiently, it is important to note that when u n5p/21j t , the pressure within the piston chamber should equal the intake pressure, Pi . This means that the valveplate slot has effectively facilitated a full pressure transition from the discharge pressure, Pd , to the intake pressure Pi . By setting Pn equal to Pi and u n equal to p/21j t , Eq. ~9! may be solved to determine the proper length of the valveplate slot for creating the full pressure transition. This result is given by （ 11） The reader should note that this valve plate is optimized for only one operating condition of the pump. Similar analysis can be done for Region 4 where the pressure transition being achieved is between the intake pressure, Pi , and the discharge pressure, Pd . In this region, the pressure within the nth piston chamber is given by （ 12） where K1b 5AbCdA2/r and K2b 5b/Vbv. Note: in these expressions, the bottomdeadcenter slot area, Ab , is a constant and Vb is the fluid volume in the piston chamber when u n53p/2. As a part of this analysis, it can be shown that the flow out of the piston chamber may be written as （ 13） and that the appropriate slot length at bottomdeadcenter is given by （ 14） To summarize the approximate pressure results of this section, the following piecewise equation is presented for the instantaneous pressure within the nth piston chamber: （ 15） The approximate volumetric flow results of this section may be summarized using the following piecewise equation for the instantaneous dischargeflow from the nth piston chamber: （ 16）
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