Chinese Engine Development


KFX

New Member
Registered Member
Exactly why I was curious to know why the WS-20 is being involved here with C919 talks.

When I said CJ-1000A can be forced upon airlines if it is less than ideal in fuel efficiency and other economical metrics, I am assuming that would be the case but the engine is assumed to be entirely safe and worthy of comparison with western equivalents in this thrust range. The only disadvantages assumed to be those economic factors is still not so terrible a price to pay for giving the C919 an engine IF western engine purchases are banned which I think is unlikely.

I did actually discuss and note the economic aspects and the safety so I'm not sure what latenlazy and you are referring to. Anyway hope that clears things up.

In summary the CJ-1000A is not ready yet in the sense of passing preliminary performance and reliability/safety standards for commerical airliners and if it ever does, let's assume it doesn't match the very best in economic factors (which is fair because PW GE RR CFM IAE have much more experience in the natural competition). But even if it passes the preliminary certifications just so that it's worthy of application on airliners, the CCP can still force the engine on the C919 if there are no alternatives, before the design can match economic performance of western engines. This is a smallish price to pay because Chinese airlines servicing domestic customers (so no American FAA approval) don't absolutely must need the very best in efficiency. I'm not sure what the monetary gap would be per C919 flight but I'm more than certain we're talking very small beans until it flies enough hours. Anyway all that is sort of off-set with cheaper fuel sources although the opportunity cost is there. What sort of economic inefficiency levels are we even assuming here. It could be marginal if it exists at all.
It's not so much a question of forcing the engine on Comac, but ordering Chinese leasing companies and airlines to opt for the CJ-1000A when they make obligatory C919 orders. Still, I would expect users to divide their orders between LEAP-1C/CJ-1000A so as to ensure some redundancy if the Chinese powerplant doesn't work as planned. Also, if trade relations with the west continue to deteriorate, one advantage for a local engine is that it is relative sanction proof. Earlier this year the Trump administration was talking about blocking the transfer of LEAP engines to China, until they realised that this would be bad, bad news for American jobs.
 

by78

Brigadier


News on a successful high-altitude engine test, one of several apparently. Judging by the information provided in the article – specifically the weight of each fan blade being tens of kilograms – this engine is a high-bypass turbofan. WS-20 maybe? Link to the original Chinese article is below, with the original text and a Google translation immediately following.

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那天凌晨4时,月明星稀,航空工业试飞中心某发动机高原试飞车辆匆匆从西安阎良出发,义无反顾地奔向雪域高原。试飞人背负着行囊,带着满心期许挺进祖国之巅。

历经两天的长途跋涉,大家终于抵达了本次试验的第一站——海拔2840米的格尔木机场。刚到宾馆,放下行囊,课题人员就迅速投入工作,与飞行机组协调任务,介绍试验方法、注意事项、可能出现的问题以及处理措施。

为了确保试验万无一失,课题组人员张浩、翟亚浩早在一个多月前就开始了技术准备,深入分析以往高原起动数据及所出现的问题,与发动机研制相关单位协调处置方案,反复推演起动试验流程,分析试验风险点,制定处置方案。

高原起动,是航空发动机设计定型阶段的重要考核内容之一,其起动性能反映了发动机对高原压力环境的起动适应能力。发动机的成功起动,是进行所有试验科目的前提。很多人都是第一次上高原,在格尔木,大家陆续出现了高原反应,但是没有一个人退缩。

按照计划,大家首先要在格尔木机场进行试验前的准备工作,主要是试验机桨叶的安装以及一些检查工作,这在高原就没那么轻松了。几十千克重的桨叶显得异常沉重,需要课题人员配合地勤人员抬起桨叶,爬上2米多高的梯子,每一步都是那么的沉重。第一片桨叶的安装往往是比较关键且比较费时的,需要大家的相互配合,尤其是桨叶末端的人需要控制桨叶各个方向的移动,是最耗费体力的。不巧的是,这天正好起风了,更增加了这项工作的难度。平日里可能两三分钟就能安装好一片桨叶,这次却花费了半个多小时,进行了近百次桨叶的移动。安装完成后,大家早已是气喘吁吁。有了第一次的经验,后续的安装速度有所加快,当天完成了试验前所有的准备工作。两天后的试验中,当机组人员给出“起动成功、一切参数正常”的手势时,大家悬着的那颗心终于放了下来,试验现场响起了热烈的掌声,这几天的努力没有白费。

结束前期格尔木机场的试验任务后,大家又奔赴高原试验的终极之站——地处雪山深处的某高高原试验场。这里空气含氧量不到海平面的60%,4000多米的高海拔在无形中给所有人造成了巨大的心理压力。风云突变的气候和强烈的紫外线让许多人都望而却步,却挡不住航空试飞人的行程。

正式试验这一天,天晴得像一张蓝纸,几片薄薄的白云像被阳光晒化了似的随风缓缓浮游着,试验人员无暇欣赏这高原所独有的美景,试验流程已经填满了他们的思绪。他们深知,高原的起动试验是本次高原试验的重中之重,是对发动机起动能力的终极考验之一,极有可能出现超温、喘振甚至熄火等异常情况。

机组人员执行起动程序后,发动机开始工作,但发动机转速上升较慢,而发动机排气温度持续升高,接近限制值,大家手里都捏了一把汗,随后张浩根据起动过程中的参数,很快给出了详细原因并建议可继续进行试验。机组人员继续执行起动程序,当熟悉的发动机声音响起,课题人员凝重的表情释然了,内心抑制不住地高兴。当机组人员给出发动机起动成功的手势时,所有人都兴奋异常。
前前后后几个月的高原试飞让某发动机试飞团队每一个人都出现了高原红。攻关克垒,所向披靡,他们在极限中突破自我,在细致中创造历史。他们让航空报国精神驰骋在雪域高原。而这精神,在航空试飞人的心中,永远不会褪色……


At 4 o'clock in the morning that day, the moon was scarce, and a certain engine plateau test vehicle of the Aviation Industry Test Center hurriedly set off from Yanliang, Xi'an, and ran to the snowy plateau without hesitation. The test pilot carried his luggage and advanced to the top of the motherland with full expectations.

After two days of long journey, everyone finally arrived at the first stop of this test-Golmud Airport at an altitude of 2,840 meters. As soon as they arrived at the hotel and put down their bags, the subject personnel quickly went into work, coordinated tasks with the flight crew, and introduced test methods, precautions, possible problems and treatment measures.

In order to ensure that the test is foolproof, the research team members Zhang Hao and Zhai Yahao began technical preparations more than a month ago, in-depth analysis of past plateau starting data and problems that occurred, coordinated treatment plans with relevant engine development units, and repeatedly deduced the starting test process. , Analyze the test risk points and formulate a disposal plan.
Plateau starting is one of the important assessments in the design and finalization phase of an aero engine. Its starting performance reflects the engine’s starting adaptability to the plateau pressure environment. The successful start of the engine is a prerequisite for all test subjects. Many people have gone to the plateau for the first time. In Golmud, everyone has experienced altitude sickness, but none of them flinched.

According to the plan, everyone will first prepare for the test at Golmud Airport, mainly the installation of the test machine's blades and some inspections, which is not so easy on the plateau. The blades weighing tens of kilograms are extremely heavy, and the subject personnel need to cooperate with the ground crew to lift the blades and climb the ladder more than 2 meters high. Each step is so heavy. The installation of the first blade is often critical and time-consuming, and requires everyone’s cooperation, especially the person at the end of the blade needs to control the movement of the blade in all directions, which is the most physically demanding. Unfortunately, it happened to be windy this day, which made the task more difficult. A blade can be installed in two or three minutes on weekdays, but this time it took more than half an hour to move the blade nearly a hundred times. After the installation is complete, everyone is already out of breath. With the first experience, the subsequent installation speed has been accelerated, and all the preparatory work before the test was completed that day. In the test two days later, when the crew gave a gesture of "start successfully, all parameters are normal", the hanging heart of everyone finally let go, and there was warm applause at the test site. The efforts of the past few days were not in vain.

After the end of the previous test mission at Golmud Airport, everyone went to the ultimate station of the plateau test-a high plateau test site in the depths of the snow-capped mountains. The oxygen content of the air here is less than 60% of sea level, and the high altitude of more than 4,000 meters has caused tremendous psychological pressure on everyone invisibly. The abrupt climate and strong ultraviolet rays discouraged many people, but they could not stop the flight test pilots.
On the day of the formal experiment, the sky was as sunny as a piece of blue paper, and a few thin white clouds floated slowly with the wind as if it had been burned by the sun. The experimenters had no time to appreciate the unique beauty of this plateau. Filled their thoughts. They are well aware that the high-altitude starting test is the top priority of this high-altitude test, and it is one of the ultimate tests of the engine's starting ability. It is extremely likely that abnormal conditions such as over-temperature, surging or even flameout will occur.

After the crew performed the starting procedure, the engine started to work, but the engine speed rose slowly, and the engine exhaust temperature continued to rise, approaching the limit value. Everyone squeezed a sweat in their hands. Then Zhang Hao followed the parameters during the starting process. , Gave a detailed reason and suggested that the experiment can be continued. The crew continued to perform the starting procedure. When the familiar engine sound rang, the subject personnel's solemn expression was relieved, and they couldn't help but feel happy. When the crew gave a gesture of successful engine start, everyone was extremely excited.

The plateau test flight for a few months before and after made everyone in a certain engine flight test team appear plateau red. Overcoming obstacles, invincible, they break through their limits and create history in detail. They let the spirit of aviation serve the country gallop on the snow-covered plateau. And this spirit will never fade in the hearts of aviation test pilots...
 
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Deino

Lieutenant General
Staff member
Super Moderator
Registered Member
I stumbled across the no. 15 in the title, which is always most interesting, but it seems more likely related to the number of engine stages than the WS-15?!

一种推比15级航空发动机设想,采用新原理涡轮盘极大提高单级增压比
= A design of a 15-stage aero engine with a thrust ratio, which uses a new principle turbine disc to greatly improve the single-stage boost ratio

Anyone with an idea what kind of engine this is?

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1602938237432.png
 

latenlazy

Colonel
I stumbled across the no. 15 in the title, which is always most interesting, but it seems more likely related to the number of engine stages than the WS-15?!



= A design of a 15-stage aero engine with a thrust ratio, which uses a new principle turbine disc to greatly improve the single-stage boost ratio

Anyone with an idea what kind of engine this is?

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View attachment 64623
T:W ratio of 15. So basically the next generation engine after the WS-15.
 

siegecrossbow

Brigadier
Staff member
Super Moderator
I stumbled across the no. 15 in the title, which is always most interesting, but it seems more likely related to the number of engine stages than the WS-15?!



= A design of a 15-stage aero engine with a thrust ratio, which uses a new principle turbine disc to greatly improve the single-stage boost ratio

Anyone with an idea what kind of engine this is?

Please, Log in or Register to view URLs content!

View attachment 64623
Might be the variable cycle engine you guys were speculating about.
 

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