关于变循环航空发动机（vce），如美国ge的f120，为什么要用到一个核心机驱动的风扇级(cdfs)？ 我只知道这样做是为了变涵道比，使得高速飞行时为小涵道比（近似涡喷），低速时为大涵道比（近似涡扇），但不明白为何要用核心机驱动第二个风扇，这样的双外涵 ...

这种构型的压缩系统由两级自适应风扇、核心机驱动风扇（cdfs）、高压压气机和有别于其他构型的叶尖风扇组成（流路如图5所示）。

为响应美国空军对发动机概念的需求及解决节流阀相关安装损失的问题，ge于1973年提出了可调涵道（moby）变循环概念。 其 实质是一种三转子分开排气具有涵道燃烧室的涡扇发动机 。

CDFS是GE公司20世纪60年代为F-22研制YF120变循环发动机提出的新型压缩部件。 不同于传统风扇，CDFS是和高压压气机一起由高压涡轮驱动，具有较宽的流量范围，可以适应整机不同涵道比的匹配需求。 随后，美国又在“自适应通用发动机技术”（ADVENT）计划中开发和验证了压比可控的自适应循环发动机，其压缩部件特点是在常规外涵道外增加了第三涵道，实现调节流量，提高发动机热管理的能力。 随着发动机更高推重比的发展需求，多级轴流压气机将向更高压比的 …

cdfs能改变发动机的风扇压比（fpr），以更好地与飞行状态相匹配；同时能够合理分配涡轮负荷，并允许在流量恒定、推力级范围内，调节发动机的推力。

2011年11月7日 · HOFFMAN ESTATES, IL -- GE Capital, Commercial Distribution Finance (CDF) today announced upgrades to the Customer Online Management System (COMS), its proprietary inventory management tool. In response to user feedback, the newest version provides manufacturers with their most-requested enhancements.

CHICAGO, Jan. 13, 2016 - Commercial Distribution Finance (CDF), a business of GE Capital announced today it has extended its inventory financing program with Branson Tractor, a tractor distribution company, through 2019.

2012年6月14日 · HOFFMAN ESTATES, IL -- GE Capital, Commercial Distribution Finance (CDF) today announced significant upgrades to its online inventory finance management tool used by dealers across a wide range of durable consumer products industries including recreational vehicles, marine, motorsports, technology, and lawn and garden.

2015年10月13日 · Wells Fargo & Company (NYSE: WFC) announced today that it has signed an agreement to purchase GE Capital’s Commercial Distribution Finance and Vendor Finance platforms as well as a portion of its Corporate Finance business. The acquisition includes total assets of approximately $32 billion as well as businesses employing approximately 3,000 ...

GE Capital's Commercial Distribution Finance (CDF) business is a provider of customized inventory financing to fund the flow of finished durable goods from manufacturers to dealers. You're one click away from the most comprehensive, unmatched analyst expertise in tech, in-depth private company data and a platform that brings it all together.