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The viscosity of a hydraulic fluid should be ? Journey > visibility

exemple question 143
The lowest to minimize power consumption resistance to flow. The viscosity must be as low as possible to limit power required the operation of system reducing resistance of flow.


The hydraulic systems which works correctly is shown in the figure 831 ?

exemple question 144
The hydraulic systems which works correctly shown in figure 831 The lowest to minimize power consumption resistance to flow. The non return valve (the directional arrow) after pumps are unidirectional flow devices used primarily in hydraulic systems to eliminate potential damage caused fluid back pressure diagram n°2 the only one correct.


One of the functions of an accumulator in a hydraulic system is ?

exemple question 145
One of functions of an accumulator in a hydraulic system To damp pressure surges in system. The function of accumulator in hydraulic system to receive store excess oil pumped through system which used to compensate sudden increase in loads.


exemple question 146
In a hydraulic system overheat detectors are mostly installed To damp pressure surges in system. The overheat detector fitted at pump to give indication of possible pump failure (t) the temperature probe location (q) quantity (p) pressure the electric motor driven pumps do a large part of work to produce flow the hydraulic system harder they work hotter they get the engine driven pumps are not fitted with an overheat detector since engines already have overheat fire detection systems.


exemple question 147
Which of these statements about an aeroplane's hydraulic system correct The filters pressure relief valve(s) by pass valve(s) the fire shut off valve are safety features installed in system. The overheat detector fitted at pump to give indication of possible pump failure (t) the temperature probe location (q) quantity (p) pressure the electric motor driven pumps do a large part of work to produce flow the hydraulic system harder they work hotter they get the engine driven pumps are not fitted with an overheat detector since engines already have overheat fire detection systems.


exemple question 148
The level in a hydraulic reservoir will Fluctuate with accumulator pressure. The overheat detector fitted at pump to give indication of possible pump failure (t) the temperature probe location (q) quantity (p) pressure the electric motor driven pumps do a large part of work to produce flow the hydraulic system harder they work hotter they get the engine driven pumps are not fitted with an overheat detector since engines already have overheat fire detection systems.


exemple question 149
Purposes of an accumulator in an hydraulic system are 1 to damp pressure fluctuations 2 to cool hydraulic fluid 3 to serve as a limited alternate source of pressure 4 to serve as a main pressure source normal operation the combination that regroups all of correct statements Fluctuate with accumulator pressure. The overheat detector fitted at pump to give indication of possible pump failure (t) the temperature probe location (q) quantity (p) pressure the electric motor driven pumps do a large part of work to produce flow the hydraulic system harder they work hotter they get the engine driven pumps are not fitted with an overheat detector since engines already have overheat fire detection systems.


8
The purpose of an accumulator in an hydraulic system to Fluctuate with accumulator pressure. The overheat detector fitted at pump to give indication of possible pump failure (t) the temperature probe location (q) quantity (p) pressure the electric motor driven pumps do a large part of work to produce flow the hydraulic system harder they work hotter they get the engine driven pumps are not fitted with an overheat detector since engines already have overheat fire detection systems.


9
The type of hydraulic fluid which has greatest resistance to cavitation Fluctuate with accumulator pressure. cavitation occurs when a liquid moves within tubing or pipes at very fast speeds causing absolute pressure of liquid to drop drastically this process occurs with little loss of heat if absolute pressure drops below vapour pressure of liquid cavitation will form this phenomenon more serious in viscous liquids than in thin liquids cavitation causes separation of gases that are within liquid (such as air or water vapour) from liquid itself bubbles would form then collapse in case of a liquid entering suction side of a pump pressure would be low for liquid to move from one place to another it would have to expend energy thus causing a further decrease in pressure the hydraulic fluid used will be synthetic because of high temperatures involved the lesser risk of cavitation compared other fluids (mineral oil or vegetable oil based fluids).


10
Filtration in a hydraulic system usually ensured Filters in both pressure return lines. cavitation occurs when a liquid moves within tubing or pipes at very fast speeds causing absolute pressure of liquid to drop drastically this process occurs with little loss of heat if absolute pressure drops below vapour pressure of liquid cavitation will form this phenomenon more serious in viscous liquids than in thin liquids cavitation causes separation of gases that are within liquid (such as air or water vapour) from liquid itself bubbles would form then collapse in case of a liquid entering suction side of a pump pressure would be low for liquid to move from one place to another it would have to expend energy thus causing a further decrease in pressure the hydraulic fluid used will be synthetic because of high temperatures involved the lesser risk of cavitation compared other fluids (mineral oil or vegetable oil based fluids).


11
The relationship between pressure force and area Force = pressure x area. cavitation occurs when a liquid moves within tubing or pipes at very fast speeds causing absolute pressure of liquid to drop drastically this process occurs with little loss of heat if absolute pressure drops below vapour pressure of liquid cavitation will form this phenomenon more serious in viscous liquids than in thin liquids cavitation causes separation of gases that are within liquid (such as air or water vapour) from liquid itself bubbles would form then collapse in case of a liquid entering suction side of a pump pressure would be low for liquid to move from one place to another it would have to expend energy thus causing a further decrease in pressure the hydraulic fluid used will be synthetic because of high temperatures involved the lesser risk of cavitation compared other fluids (mineral oil or vegetable oil based fluids).


12
In a commercial transport aeroplane landing gear normal operating system usually Hydraulically driven. cavitation occurs when a liquid moves within tubing or pipes at very fast speeds causing absolute pressure of liquid to drop drastically this process occurs with little loss of heat if absolute pressure drops below vapour pressure of liquid cavitation will form this phenomenon more serious in viscous liquids than in thin liquids cavitation causes separation of gases that are within liquid (such as air or water vapour) from liquid itself bubbles would form then collapse in case of a liquid entering suction side of a pump pressure would be low for liquid to move from one place to another it would have to expend energy thus causing a further decrease in pressure the hydraulic fluid used will be synthetic because of high temperatures involved the lesser risk of cavitation compared other fluids (mineral oil or vegetable oil based fluids).


13
Generally on modern jet transport aircraft how can landing gear be extended if there a complete hydraulic system failure Hydraulically driven. cavitation occurs when a liquid moves within tubing or pipes at very fast speeds causing absolute pressure of liquid to drop drastically this process occurs with little loss of heat if absolute pressure drops below vapour pressure of liquid cavitation will form this phenomenon more serious in viscous liquids than in thin liquids cavitation causes separation of gases that are within liquid (such as air or water vapour) from liquid itself bubbles would form then collapse in case of a liquid entering suction side of a pump pressure would be low for liquid to move from one place to another it would have to expend energy thus causing a further decrease in pressure the hydraulic fluid used will be synthetic because of high temperatures involved the lesser risk of cavitation compared other fluids (mineral oil or vegetable oil based fluids).


14
The type of brake unit found on most transport aeroplanes a Hydraulically driven. cavitation occurs when a liquid moves within tubing or pipes at very fast speeds causing absolute pressure of liquid to drop drastically this process occurs with little loss of heat if absolute pressure drops below vapour pressure of liquid cavitation will form this phenomenon more serious in viscous liquids than in thin liquids cavitation causes separation of gases that are within liquid (such as air or water vapour) from liquid itself bubbles would form then collapse in case of a liquid entering suction side of a pump pressure would be low for liquid to move from one place to another it would have to expend energy thus causing a further decrease in pressure the hydraulic fluid used will be synthetic because of high temperatures involved the lesser risk of cavitation compared other fluids (mineral oil or vegetable oil based fluids).


15
The reason fitting thermal plugs to aeroplane wheels that they Release air from tyre in event of overheating. Tyres are fitted with thermal plug to release air from tyre in event of overheating after a landing (or a rejected take off) with overweight overspeed conditions tyres brakes are extremely hot thermal plug can malfunction on video you can see a tyre explosion .


16
Thermal plugs are installed in Release air from tyre in event of overheating. Tyres are fitted with thermal plug to release air from tyre in event of overheating after a landing (or a rejected take off) with overweight overspeed conditions tyres brakes are extremely hot thermal plug can malfunction on video you can see a tyre explosion .


17
In a hydraulic braking system an accumulator pre charged to 1200 psi if an electrically driven hydraulic pump started and provides a system pressure of 3000 psi pressure gauge which connected to gas section of accumulator will read Release air from tyre in event of overheating. The question states the pressure gauge connected to gas section of accumulator thus if electrically driven hydraulic pump started provides a system pressure of 3000 psi you will read a pressure of 3000 psi.


18
The modern anti skid processes are based on use of a computer whose input data 1 idle wheel speed measured 2 braked wheel speed measured 3 brake temperature measured 4 desired idle wheel train slipping rate5 tire pressurethe combination regrouping all correct statements Release air from tyre in event of overheating. 3 steps during landing roll 1) if wheels are not braked at all they all follow kinematics that is speed of airplane (and wheel radius of course) directly determine their angular speed deceleration if we would use only spoilers thrust reversers we would have pure kinematic deceleration of wheels hence no slipping (of course we presume that runway surface conditions are ideal) in this case all wheels are on their 'idle' speed all time in sense that they are not being braked externally the brakes they just 'naturally' decelerate together with airplane idling all time 2) but if brakes are applied during landing roll that means that at first moment none of wheels idle any more! now they are not just decelerating with airplane they are having an additional deceleration from brakes being applied on them that means that there some small physical slipping at contact area of tire the runway surface 3) now computer monitors situation has those braked wheels speed input now let's say simplicity that one of wheel some reason gains such a high angular deceleration which would soon lead to blockage (zero angular speed) of that wheel computer prevents that commanding servo on that wheel to reduce brakes on that particular wheel from that moment on that particular wheel idling at desired wheel train slipping rate.


19
When a landing gear wheel hydroplaning its friction factor around Release air from tyre in event of overheating. 3 steps during landing roll 1) if wheels are not braked at all they all follow kinematics that is speed of airplane (and wheel radius of course) directly determine their angular speed deceleration if we would use only spoilers thrust reversers we would have pure kinematic deceleration of wheels hence no slipping (of course we presume that runway surface conditions are ideal) in this case all wheels are on their 'idle' speed all time in sense that they are not being braked externally the brakes they just 'naturally' decelerate together with airplane idling all time 2) but if brakes are applied during landing roll that means that at first moment none of wheels idle any more! now they are not just decelerating with airplane they are having an additional deceleration from brakes being applied on them that means that there some small physical slipping at contact area of tire the runway surface 3) now computer monitors situation has those braked wheels speed input now let's say simplicity that one of wheel some reason gains such a high angular deceleration which would soon lead to blockage (zero angular speed) of that wheel computer prevents that commanding servo on that wheel to reduce brakes on that particular wheel from that moment on that particular wheel idling at desired wheel train slipping rate.


20
From following fuselage profile sort them from worst to best one concerning pressurization 818 Release air from tyre in event of overheating. N°1 clearly weakest would only be used on an unpressurised aircraft (twin otter example) n°2 geometrically strongest from a pressurisation point of view as hoop stresses can be uniform on whole cross section n°3 'double bubble' type where two circles intersect connected via a floor not best choice but clearly better than n°4 n°4 pressurization constraints will not be optimal on an oval format this question also exists with statement 'from following fuselage profile sort them from worst to best one concerning pressurization ' answer 1 4 3 2.



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