[coconut17]

السلام عليكم ورحمه الله وبركاته
سؤال الى اهل الخبره ما هو معنى compressor stall ومعنى wet start بالشرح لو امكن؟؟؟

[FaHaD_7arB]

Engine wet start

This happened when the the fuel start to inject into the combustion chamber and ignition system
has an abnormal delay(ignition did not start to work at the right time),this can be noticed
by a fire coming out the tail-pipe by ground crew and by the high EGT indication in the cockpit.

In P&W4000, during engine shut down two fuel nozzels will keep injecting fuel and stop after that for the the next engine run, in the next engine run you will notice
smoke coming out the tail-pipe, but as per thire standards this is not considered as wet start

Compressor stall

When the air flow going through the compressor is not
enough or inadequate
air flow passing through it,in this case stall will start to happen and it will lead to somthing called (surge). when the surge exists
, a bang sound coming from the engine can be heard plus back fire

see this vedio for more info about surge

[youtube]https://www.youtube.com/watch?v=pE2LeVQ2DtM[/youtube]

[coconut17]

الف شكر على الشرح الوافى

[الردهان]

يعطيك العافية

[fly-iy]

A compressor stall is a situation of abnormal airflow resulting from a stall of the aerofoils within the compressor. Stall is found in dynamic

[طق طق]

شكرا جزيلا على المعلومات المفيده وكل عام وانت بخير بمناسبه الشهر الفضيل.
تقبل تحياتي.

[mechanic]

يسلموو كابتن فهد على الشرح والمقطع

بارك الله فيك

[eng.salah aliraqe]

السلام عليكم جميعا......حبت ارد على اخويا على السؤال..اول مره اني اشارك وياكم فسمحولي ارد...........

COMPRESSOR STALL:.its is imbalance between inlet velocity and comp. rotational speed.
or
its is an excessive angle of attack

تحياتي الك اتمنى ان اكون كفيت وفيت ...رمضان كريم ......

[Tarig Elsheikh]

This characteristic has been called both " Surge " and " Stall " in the past , but is more properly called SURGE when it is response of the entire engine. The word stall applies to the action occuring at each individual compressor blade. Compressor surge , also called Compressor stall , is a phenomenon which is difficult to understand because it is usually caused by complex combination of factors . The basic cause of compressor surge is fairly simple , each blade in an axial flow compressor is a miniature airplane wing which , when subjected to a higher angle of attack , will stall just as an airplane stalls. Surge may define as results from an unstable air condition within the compressor. Pilot or engine operator has no instrument to tell him that one or more blades are stalling. He must wait until the engine surges to know that. The unstable condition of air is often caused from air piling up in the rear stages of the compressor. Surge may become sufficiently pronounce to cause lound bangs and engine vibration. In most case , this condition is of short duration , and will either correct itself or can be corrected by retarding the throttle or power lever to Idle and advanncing it again , slowly. Among other things , to minimize the tendency of a compressor to surge , the compressor can be "unload" during certain operating conditions by reducing the pressure ratio across the compressor for any giving airflow. One method of doing this is by bleeding air from the middle or toward the rear of the compressor. In dual axial compressor engines , air is often bled from between the low and the high pressure compressor. Air bleed ports are located in the compressor section. These ports are fitted with automatic , overboard bleed valves which usually operate in a specified range of engine RPM. Some large engine have been provided with variable-angle stators ( variable stators) in a few of the forward compressor stages. The angle of these vanes change automatically to prevent the choking of the downstream compressor stages as engine operating conditions vary.

[elwadi]

Engine wet start

This happened when the the fuel start to inject into the combustion chamber and ignition system


has an abnormal delay(ignition did not start to work at the right time),this can be noticed


by a fire coming out the tail-pipe by ground crew and by the high EGT indication in the cockpit.

In P&W4000, during engine shut down two fuel nozzels will keep injecting fuel and stop after that for the the next engine run, in the next engine run you will notice


smoke coming out the tail-pipe, but as per thire standards this is not considered as wet start

Compressor stall

When the air flow going through the compressor is not


enough or inadequate


air flow passing through it,in this case stall will start to happen and it will lead to somthing called (surge). when the surge exists


, a bang sound coming from the engine can be heard plus back fire

thank you

[libyan-ame]

شكراً للجميع

[FaHaD_7arB]

اقتباس:     المشاركة الأصلية كتبت بواسطة elwadi  

Engine wet start

This happened when the the fuel start to inject into the combustion chamber and ignition system

has an abnormal delay(ignition did not start to work at the right time),this can be noticed

by a fire coming out the tail-pipe by ground crew and by the high EGT indication in the cockpit.

In P&W4000, during engine shut down two fuel nozzels will keep injecting fuel and stop after that for the the next engine run, in the next engine run you will notice

smoke coming out the tail-pipe, but as per thire standards this is not considered as wet start

Compressor stall

When the air flow going through the compressor is not

enough or inadequate

air flow passing through it,in this case stall will start to happen and it will lead to somthing called (surge). when the surge exists

, a bang sound coming from the engine can be heard plus back fire

thank you

يعني لو نسخت اجابتي و حطيتها بموضوع ثاني ممكن
لكن
تنسخها وتنزلها بنفس الموضوع..هذا اغرب تصرف مر علي بحياتي بصراحه..

[zahoo27]

شكر على الشرح الوافى