羅爾斯-羅伊斯公司
“康維”（Conway）發(fā)動(dòng)機(jī)
Rolls-Royce Conway
Rolls-Royce RM60
RM60發(fā)動(dòng)機(jī)是按英國(guó)海軍部要求設(shè)計(jì)的，這是具有良好巡航經(jīng)濟(jì)性的 發(fā)動(dòng)機(jī)。雖然它是以航空發(fā)動(dòng)機(jī)為基礎(chǔ)，但從開始就是作為船用燃?xì)獍l(fā)動(dòng)機(jī)設(shè)計(jì)的。兩臺(tái)RM60發(fā)動(dòng)機(jī)于1953年在以前的蒸汽發(fā)動(dòng)機(jī)炮艇HMS Grey Goose號(hào)上下海。這是世界上第一艘以燃?xì)鉁u輪發(fā)動(dòng)機(jī)為動(dòng)力的戰(zhàn)艦。
Produced in response to an Admiralty contract for a coastal-craft engine with good cruising economy, the RM60, although based on aeroengine philosophy, was designed from the first as a marine gas turbine. Two RM60s went to sea in 1953 in the former steam gunboat HMS Grey Goose, the world's first warship to be powered solely by gas turbines.
羅爾斯-羅伊斯公司
RM60發(fā)動(dòng)機(jī)
20: Thrust distribution
第二十章 推力分布
INTRODUCTION
緒言
推力分布
計(jì)算推力的方法
發(fā)動(dòng)機(jī)推力計(jì)算
壓氣機(jī)機(jī)匣
擴(kuò)散器涵道
燃燒室
渦輪裝置
排氣袋置和噴管
推進(jìn)噴管
發(fā)動(dòng)機(jī)
傾斜燃燒室
加力燃燒
推力分布
2．圖20-1是一種典型的單轉(zhuǎn)子軸流式渦輪噴氣發(fā)動(dòng)機(jī)，表示了主要的向前的和向后的力作用于何處。用第2章表示的發(fā)動(dòng)機(jī)工作循環(huán)可解釋這些力的來源。
1. Although the principles of jet propulsion (see Part 1) will be familiar to the reader, the distribution of the thrust forces within the engine may appear somewhat obscure- These forces are in effect gas loads resulting from the pressure and momentum changes of the gas stream reacting on the engine structure and on the rotating components. They are in some locations forward propelling forces and in others opposing or rearward forces. The amount that
Contents
Introduction Distribution of the thrust forces Method of calculating the thrust forces Calculating the thrust of the engine
Compressor casing Diffuser duct Combustion chambers Turbine assembly Exhaust unit and jet pipe Propelling nozzle Engine Inclined combustion chambers
Afterburning
Page 207 207 209 209
212
緒言
1．雖然噴氣推進(jìn)原理(見第1章)對(duì)讀者來說可能是熟悉的。但是，對(duì)發(fā)動(dòng)機(jī)內(nèi)部的推力分布可能會(huì)有點(diǎn)不太清楚。這些力實(shí)際上是燃?xì)饬鞯膲毫蛣?dòng)量變化導(dǎo)致的氣體載荷對(duì)發(fā)動(dòng)機(jī)結(jié)構(gòu)件和轉(zhuǎn)動(dòng)部件產(chǎn)生的反作用力。在一些位置，它們是向前的推進(jìn)力，在另外一些地方，則是相反的即向后的力。向前的力的總和超過向后的力的總和的總額通常被稱作發(fā)動(dòng)機(jī)的額定推力。
the sum of the forward forces exceeds the sum of the rearward forces is normally known as the rated thrust of the engine.
DISTRIBUTION OF THE THRUST FORCES
2. The diagram in fig. 20-1 is of a typical single-spool axial flow turbo-jet engine and illustrates where the main forward and rearward forces act. The origin of these forces is explained by following the engine working cycle shown in Part 2.
207
3.在喜歡開始時(shí)，空氣被吸入發(fā)動(dòng)機(jī)并被壓縮。通過壓氣機(jī)各級(jí)的向后加速和總的壓力升高產(chǎn)生一個(gè)很大的向前的反作用力。在空氣流程的下一步，空氣通過擴(kuò)壓氣。它在這里產(chǎn)生一個(gè)小的反作用力，方向也向前。
5.當(dāng)膨脹的燃?xì)怆x開燃燒室和流經(jīng)導(dǎo)向器葉片時(shí)，它們被加速并偏轉(zhuǎn)到渦輪的工作葉片上（第5章）。由于燃?xì)饬鞯募铀俸推D(zhuǎn)，加上后來進(jìn)入噴管時(shí)變直，就產(chǎn)生了相當(dāng)大的“阻力”；因而靜止葉片和轉(zhuǎn)動(dòng)葉片都受到很大的向后的力，其大小可在圖中看出。當(dāng)燃?xì)饬魍ㄟ^排氣系統(tǒng)（第6章）時(shí)，較小的向前的力可作用于內(nèi)錐或尾錐上。但一般來說，只產(chǎn)生向后的力，它們是由于燃?xì)饬髟谕七M(jìn)噴管中的“阻力”所致。
6.可以看到，在空氣通過發(fā)動(dòng)機(jī)時(shí)，其速度和壓力會(huì)發(fā)生變化（第2章）。例如，在需要將速度（動(dòng)）能轉(zhuǎn)換成壓力能的地方，通道呈擴(kuò)散形，與用于壓氣機(jī)擴(kuò)壓器上的形狀類似。相反，在需要將儲(chǔ)存在燃燒后的燃?xì)庵械哪芰哭D(zhuǎn)換成速度的地方，就采用與渦輪中類似的收斂通道或噴管。在轉(zhuǎn)換成速度能的地方，就產(chǎn)生“阻力”載荷或向后的力；在轉(zhuǎn)換成壓力能的地方，就產(chǎn)生向前的力。第2章中的圖2-3表示了發(fā)動(dòng)機(jī)上這兩處的速度和壓力變化。
Thrust distribution
圖20-1 一種典型的單轉(zhuǎn)子軸流式發(fā)動(dòng)機(jī)的推力分布
Fig. 20-1 Thrust distribution of a typical single-spool axial flow engine.
排氣裝置
和噴管
燃燒室
渦輪
擴(kuò)壓器
壓氣機(jī)
推進(jìn)噴管
4.空氣從擴(kuò)壓氣進(jìn)入燃燒室（第4章），在那里受到加熱。氣體在后來的膨脹和加速中，在燃燒室壁上作用有很大的向前的力。
向后的燃?xì)廨d荷46，678磅
向前的燃?xì)廨d荷57，836磅
3.
At the start of the cycle, air is induced into the engine and is compressed. The rearward accelera-tions through the compressor stages and the resultant pressure rise produces a large reactive force in a forward direction. On the next stage of its journey the air passes through the diffuser where it exerts a small reactive force, also in a forward direction,
4.
From the diffuser the air passes into the combustion chambers (Part 4) where it is heated, and in the consequent expansion and acceleration of the gas large forward forces are exerted on the chamber walls.
5.
When the expanding gases leave the combustion chambers and flow through the nozzle guide vanes they are accelerated and deflected on to the blades of the turbine (Part 5). Due to the acceleration and deflection, together with the subsequent straighten-ing of the gas flow as it enters the jet pipe, consider-able 'drag' results; thus the vanes and blades are subjected to large rearward forces, the magnitude of
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