Citat:
Nu var det ju motorn som hittades på Murray Street inne på Manhattan som jag talade om och länkade till... 
Dessutom ger en sökning i tråden på "Murray street" endast ett inlägg nr. 22221 som tar upp det ämnet...
Dessutom ger en sökning i tråden på "Murray street" endast ett inlägg nr. 22221 som tar upp det ämnet...
Dock är det ungefär samma problem - det man gnällt på angående motorn på Murray street är ju att en "cooling duct" skulle vara felaktig. Det stämmer dock inte eftersom motorerna har konstruerats med båda varianterna av cooling duct. Jag får leta upp källor senare om du önskar men nu hinner jag inte.
Hittade detta så längea angående varför man bytte från en cooling duct med många komponenter till den enklare "ringen" som visas i filmerna:
Citat:
The tobi-tube duct created turbulence and thus caused a reduction in thrust (some 40,000 lbs give or take), which his insufficient to power a larger aircraft. After the P&W engineer, having teamed up with NASA engineers, the break through came with the introduction of the 7R4D engine, which was installed on 767's around 1982. This break through technology utilizes a slightly larger core (thus accounting for the additional holes), and a tubeless induction design. Instead of using a tubular design, the core uses a Radial disk with blades on its outer rings. This enhances airflow to the turbine blades and increases cooling by 2% without causing turbelance. Notice from the above THE PROBLEM, "in which tubes with nozzles (tobi-tubes) thereon are supported in the wall of the cooling air chamber (core) and are positioned to blow air tangentially against the turbine disk........Further the discharge of air from each nozzle (tobi-tube) necessarily impinges upon the adjacent tubes, and THE RESULT IS TURBULENCE THAT DETRIMENTALLY AFFECTS THE COOLING FUNCTION..."
Hence, the "tobi-tube" duct (the one you refer to as "The Assembly") was insufficient, and thus needed to be revised as it was doing harm as well as good. The break through came with the new design using a NON-ASSEMBLY cooling duct referred to as the "Radial" induction system, WHICH DID NOT RELY ON A LARGER "ASSEMBLY" (TOBI-TUBE DUCT); The development of the non-assembly cooling duct satisfied two "desired" outcomes:
1. No more turbulence robbing power
2. Less components (non-assembly)
The answer was the newly designed non-assembly, non-tubular HPT Cooling Duct TOBI system. This increased cooling by 2% percent, contributed to increased thrust, and increased fuel efficiency. Even so, towards the late 80's, the 7R4D engine would be replaced with the P4000 series engines; much larger although similar in design, and a heck of a lot more powerful (about 50,000 lbs of thrust).
Hence, the "tobi-tube" duct (the one you refer to as "The Assembly") was insufficient, and thus needed to be revised as it was doing harm as well as good. The break through came with the new design using a NON-ASSEMBLY cooling duct referred to as the "Radial" induction system, WHICH DID NOT RELY ON A LARGER "ASSEMBLY" (TOBI-TUBE DUCT); The development of the non-assembly cooling duct satisfied two "desired" outcomes:
1. No more turbulence robbing power
2. Less components (non-assembly)
The answer was the newly designed non-assembly, non-tubular HPT Cooling Duct TOBI system. This increased cooling by 2% percent, contributed to increased thrust, and increased fuel efficiency. Even so, towards the late 80's, the 7R4D engine would be replaced with the P4000 series engines; much larger although similar in design, and a heck of a lot more powerful (about 50,000 lbs of thrust).
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Senast redigerad av SnakePlisssken 2017-01-02 kl. 14:37.
Senast redigerad av SnakePlisssken 2017-01-02 kl. 14:37.
