TWI250254B - The present invention relates to a new-designed hybrid air journal bearing with best stability - Google Patents

Abstract

The present invention relates to a new-designed hybrid air journal bearing with best stability. The rows of orifices are spaced equally on the axial sections and arrayed from the center section to both sides of bearing symmetrically, with 1, 2, 3, 4 or 5 circumferential rows. The number of orifices in each circumference has to be no less than 8. The said orifice could be stepped hole with a thin needle throttle hole, which can discharge pressurized air into bearing gaps to form a lubricating film. The 5-row orifice feeding bearing has the higher threshold load capacity of rotor mass than the porous bearing when small rotor whirl occurs for a moderate rotation speed (Lambda ≈ 0.5)and a lower feeding parameter(lambdao < 10<-4>) accordingly. The above said shows that the 5-row orifice feeding bearing is more stable than the porous bearing.

Description

1250254 IX. Description of the invention: [Technical field to which the invention pertains] ▲ The present invention relates to an optimum stability mixed gas bearing design, and more particularly to a method in which the rotor of the bearing has a more =: r-pressure air pressure when rotating A new designer. Due to the advantages of cleanliness and low friction, Xiangqi Air Slip has become a high-speed clock-synthesis accessory, but the rotor of the air-pressure air-neck bearing is easy to sway and unstable. In order to overcome this - The problem, the study explores the rigidity and damping coefficient of t-text to become the age, and the stability of the transfer material has become the research theme of the researcher; for example, the use of Galerkins and the minimum mass and speed of dynamic instability , has been to improve the rigidity and damping coefficient of the bearing: good flap tilting pad and (four) gas bearing turn

Leonard and R0We by experiment] = unstable rotation ^ Because of the damping characteristics of (4), so - the focus of the researcher is (4) the quality of the pumping is produced... and ha:er); the subsequent references are not Phenomenon =: Analysis of static air bearing with different throttling modes; near == 1250254 Research report, further discussion on liquid lubricated bearings and air lubricated bearings. However, the above discussion and analysis of the rotor instability of the mixed air pressure air neck bearing is still not enough to systematically conclude this complex mechanism, which is not aimed at the mixed air pressure neck bearing in the multi-row orifice. The design of the different rows of throttling will analyze and compare the effects of the effect of rotor turbulence instability, so it is impossible to know which troughs of the number of rows have the best stability. SUMMARY OF THE INVENTION The optimal stability mixed gas bearing design of the present invention is mainly provided with several rows of orifices respectively, symmetrically to the center of the bearing, and equidistantly disposed on the axial section, and the number of orifices per row is not small. In 8 holes, : are distributed on the circumference, the shape of the orifice can be segmented holes, the material of the porous f sleeve can be made of sintered metal, and the tube is throttled at 5 rows of holes, at medium speed (Λ% G.5), and at a low intake air amount &lt;) in the state of the rotor sway, it is stable [Embodiment] The first method is not described. Referring to: Figure, the multi-row orifice of the present invention is throttled After the number of draws (1) is not less than 8 holes ^ uniform surface, each row of orifices (11) when analyzing the simulated boundary, can be: = on _, so in the numerical accuracy, the orifice (11) ', ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, (porosity) is lower than ΗΓ" cm2, air pressure enters the film lubrication layer through the porous material, assuming the axis The inside is film lubrication, and considering the air as compressibility, and the inlet flow of the porous bearing (2) is the Darcy flow. The mathematical analysis is based on the above assumptions, and the following dimensionless Renault can be derived. Equation (A) orifice throttle bearing

d W Η3

dP d n w y (B$ porous bearing

d W H3

dP2 W +Φ Η3

dP H3 dP2 1 : 2Λ d(PH) ιΑγΚ d(PH) (1) c3 or (2) where equation (2) is one more than equation (1) and is generated by the radial Darcy flow velocity Γρ of. If the shaft is in a steady state, the bearing eccentricity ratio is at . The angle of attack is nine. When a perturbation momentum of $ and six is generated, a new state is generated: left = sarcophagus + gas, φ = φ 〇 + φ χ (3) where the perturbation momentum is 5 and 4 is a harmonic motion, which can be expressed mathematically as:

Re{ l^il erb Φγ Re{ 1^1 e^} (4) In the disturbed state, the resulting dimensionless film thickness and film pressure can be mathematically expressed as: (5) // = gas-gas cos0. + stone.戎sin% 1250254 P = P〇+ + ε〇φχΡ2 (6) where the dimensionless film thickness of the steady state can be expressed as · Κ - 1 + ^ 〇〇〇 8 ^ 〇 (?) β Equation (4-6) is substituted into Reynolds equation 2), and the governing equation (A) orifice throttle bearing d2P2 can be derived under disturbance state.

Po cover + 'mouth + 2淼§ + φ, + + 2 tied to +3 (, sm0Q+ ssin^f Mcos^) (go + Α〇〇吟碧如% ji + + Ρ〇|§) + + Ρ〇 ^) ^τήβ + + 2§f + p〇p + 2s,m^ + 2§§ + ρφ =2八+ 钵—33⁄4 决 Sin0n \3 V — V — ' (^bsin^Po + h〇^) + ^(sin^〇P0- cos6&gt;〇|| + ^sin^ + + e^(cos0oPo + sin^〇^ + ^〇sin^〇P2 + /3⁄4 stomach) 御皆-£χ^θ〇一3 °^4 -) Wide Acos(6) + catch WGsin钵)] (A1) (l-SoCOsOo) where the = piece is the square of the steady state pressure; and nine is the dimensionless bearing gap. (B) Porous bearing 1250254 ^ + 2ει(φ + 2§§ + φ) + 2sAiP^ + 2§§ + P〇^) w + 2£i^PlW + Ρ〇^ + 1ε^ρ^Β + P 〇w\ (4) Camp + 2, (all ring + mouth + W hair + 2 body + chew) = 2A (- + ^^cos^q — 3^sin^〇x

A WV — V (sosm0oPo + h^) + ^i(sin^〇P〇- cos^〇|^- + ^〇sin^ + h^) + ^〇φ[(^〇^〇Ρ〇+ sin^ 〇·^^- + sin^)/2 ^ 夂 )) 2 崎 + [muscle + 2 sentence cards, 2) - 诺+咖圳· + /4Λ^(^ + - gas S4_) [^(^-Pocos ^o) + e〇MkP2+P〇sm0Q)] (Bl) where seven=1^ is the porous bearing intake parameter. In the derivation of the (Α1) and (Β1) equations, the product of the two-order perturbation quantities 3 and ^ is negligible. In order to solve the pressure perturbation amount /^ and VIII, the other program (Α1) and (Β1) respectively differentiate the disturbance amount 6 and Μ, respectively, and get 繇 繇 + 2 § + + + (ι 4(10) Θ. temp + + P0§) + 2φ(Ρι^ + 2§§ + φ) = dream (10) postal month + /% bi;) + sin0o (h^^10 1}/&gt; 0 + general (7) city record + Z ^ '( ~乃-❽叫) (A2) 9 1250254 o/p 52P〇^ ^dP〇dP2 ^ p d2P2\ ^ /3cos^〇3sQsm20o ^dF〇+ 2 孤孤+ 尸〇厌J + --———— + P0smmin (corpse 2 words + corpse. Lin) + 2 (妾) 2 (corpse 2 loaded + 2 badge + corpse bag) =M (s0sm&amp;0P2 + h〇^) + ^ (c〇s^〇-启)P0 -|Δδίη^〇+ / ^ {h〇P2 + P〇sin0〇) (A3) + + p〇l^) + ^(1 + %^)d4 -^osin^o^^ + φ + 2(^(P^ + 2§§ + P〇P)

=碧(10)ίηθ〇/5 + 私爵)+ ^sm0〇(3^s0〇+!)/&gt;〇"God (岂+ 3cos0〇Po) One corpse (ugly + 3cos^〇Pq^ + Axe 1COS you recorded + ' 普r (/^ - PGCOS0.) (B2) 2^^ + 2§|1 + /,〇^) + ^-^^)§ + ^〇sin0〇(P2§ + /&gt; §) + 2(^(p^ + 2§§ + p〇^} =^ (sosm0oP2 + /%||) + M (ccs^o - )p〇+岭2卜(跫--哺- -^sin^〇 ^ + / M r (^ρ2 + P0sin^〇) (B3) The three common boundary conditions required for solving can be expressed as ^: (8) (9) (10) i^(^Z=l) = Ρ2 (θ9Ζ=ΐ) = ο /;(^Ζ) = Ρλφ+2π,Ζ\ Ρ2φ,Ζ) = Ρ2φ^1π,Ζ) ^ (θ, Ζ) = ^ + 2^, Ζ), (^5 Ζ ) = (^+2^τ? Ζ) 10 Ϊ250254 Resolve the equations (A2) and (A3), (B2) and (B3), each requires four boundary conditions. The perturbation equation for the orifice excerpt (A2) and (A3), the fourth boundary condition is a continuous equation at the orifice position. It can be expressed as: (11) where the plant is the velocity at which the air is injected into the bearing lubrication layer via the orifice. The continuous equation (11) in the state can be derived as a city sacrifice + 2 language 4^ (1 + f-θ. temperature + + Ρ0§) + 2φ{Ρ^ Η- 2§§ + Ρ0^) ^ 2Α (^sin^ + /3⁄43⁄4) + ^ίηθ0(^ψ^ + 1)Ρ〇 + 普cosA|| + ί 普...乃-P0COS you)

(most + 3 gas,.) Bu_2(吴)·Η脊叫2 r "(A4) 11 1250254 〇iD S2p〇^ 0^0 ^p2 D ^ip2\ ^ /3cos&lt;9〇_ 3^〇 Sin2^〇^dF〇+ ιτυτυ + ^qwt) + &quot; -v~~ + hsm0(P2 build + P.) + 2 (妾(10) bag + 2 sign good + PQ·)

= Deng (_ηθ. Household 2 + /%) + For (cos0. - 3s〇sj^2^〇) PQ -Msin^〇+ / M r (/3⁄4^ + P〇sin^〇) - Α^φ (ξ) (Discrimination whistle 1f "+! (¥) (clock f2 Bu (material f) (A5) where 24 / / ^ (2 ^ ^) 2 is the orifice throttle intake parameters; and

PalPaiC^ /w = is the number of differential nodes in the axial Z direction. For porous bearings, the fourth boundary condition is the symmetry at the center of the bearing. It can be expressed as follows: Build like = 〇) = sign (θ, ζ = ο) = ο (12) ❿ Second, the numerical analysis of the disturbance equation The solution is solved by the finite difference method and computer numerical analysis: orifice throttling The bearing disturbance equations (Α2) and (A3) and its four boundary condition equations (8)-(10), (Α4) and (Α5) are simultaneously solved: the perturbation equations (B2) and (B3) of the porous bearing Four boundary condition equations (8)-(10) and (12), the pressure value in steady state. It must be found under the fixed 12 1250254 conditions and parameters, and then the household. The value is substituted into the perturbation equation to find that the disturbance pressure value under the same conditions is equal to eight, and must be specially considered. In the computer program, the disturbance pressure value and the variable must be set to double precision (double precision). To improve the convergence of numerical analysis, the convergence criterion is set to be · · The sum of the error before and after each calculation is less than 1 with respect to the sum of the variable values themselves (Γ5. 3. Calculate the stiffness and damping coefficient in the disturbed state. #力 along the axis and the axis = the component of the force R and the tangential direction a can be expressed by the following formula W + Z# water ^ (13) ^ ^ ^ (14) where /L and /τ are respectively Supporting the spread of power under steady state _ Yun" 'Gan-yan+ was once referenced [21]. In the above formula, the perturbation support force coefficient / eight integral formula sub-calculation can be obtained by the following 2i: J; ^i

^RR ^TR

^TT cosO sinO cos called sin^

dOdZ 2Π, 1 «Ιο Jo 2 ; Disturbing support force coefficient in the direction of the X and γ axes

dOdZ (15)(16) can be obtained by the following matrix transformation: 2jcr ^χγ ^JRR ^TR sin 么-cos戎sin厶-cos type Zyx Ζγγ Zpj, Ζ,γρ cos sin also 匕« cos also sin what is here The perturbation support force coefficient is a complex number, which can be divided into 13 (17) 1250254 points as follows: ^χγ S\\ Su + 7· Ζγχ Ζγγ Six S22 丁ί βΐΐ Bi2 (18) In the above formula, meaning 2, 尻And no 2 is the bearing stiffness coefficient; and 2, also and 2 is the bearing damping coefficient. 1 V. Instability instability analysis of the rotor quality of the rotating shaft. In the case of turbulence, the displacement equation can be expressed by the following linear differential equation: square M〇' ^ q ► + Al Βχΐ LI , 丄susu r 1 0 0 Af B2\ B22 Π ^21 ^22 q 0 (19) The displacement g疋 one-dimensional vector in the above equation·· contains the X component ^ and γ components in determining the minimum rotor mass that causes turbulence instability (threshold rotor mass The Ross criterion can be adopted (this uth's criterion), the rotor weight can be regarded as the total load of the bearing (F = ife ·), and the bearing support force Λ. Balance with everything. By Ross's criterion, the minimum rotor mass that causes turbulence instability can be derived from the equation of motion (19): M+^+Sn Bn+Su qx fo] M+B22m^S22 k] ί〇ί (20) Neutral The standard of neutral stability is: (2〇) has a non-zero solution, so the determinant of the coefficient matrix must be equal to zero, as follows: 14 (21) =0 1250254 to find the largest rotor that satisfies the formula (21) The mass fraction requires the use of repeated calculations of the iteration procedure and the Newton-Raphson correction method, by modifying the ratio of the shaft yaw frequency to the rotation frequency parameter 7, while other operating parameters The fixed computer program is calculated until the value of the determinant (21) is less than 1 (the convergence criterion of Γ5. VI. Symbol description a throttle radius radius of orifice dimensionless damping coefficient = ^ 4 damping coefficient damping coefficient C Concentric bearing clearance for ε= 0

Cd jet orifice coefficient

Specific heat of constant pressure of air

Cv isometric heat of the diameter of the air diameter of the diameter of the diameter of the eccentricity F pressure variable variable of pressure / = household 2 g gravity acceleration specific gravity h bearing clearance bearing clearance = (1- ε cos0 ) H〇 dimensionless bearing clearance dimensionless equilibrium bearing clearance = (1- ε〇cos^〇) 15 1250254 Η dimensionless bearing clearance dimensionless bearing clearance =Λ/61 = (1- ε cos0 )

Hw Porous bearing radial thickness thickness imaginary number = k specific heat ratio specif ic heat ratio of air = (G / G ) K porous bearing permeability probability of porous bearing L bearing length bearing length M single bearing no Dimensionless threshold rotor mass supported per bearing = = M dimensionless rotor mass of a single bearing threshold rotor mass supported per bearing

m Z direction difference node number mesh number in z direction L &quot;ISz N number of orifices per row number of orifices in a peripheral row n number of orifices per unit circumferential number of orifices per unit circumferential length =N/{2nR) p Bearing pressure pressure P dimensionless bearing pressure dimensionless pressure = / /3⁄4

Pa atmospheric pressure ambient pressure p〇 steady-state bearing pressure equilibrium pressure P〇 dimensionless steady bearing pressure dimensionless equilibrium 16 1250254 pressure - p〇/ pa

Pi dimensionless perturbation bearing pressure dimensionless perturbed disturbance pressure - pi/ pa P2 dimensionless perturbation bearing pressure dimensionless perturbed disturbance pressure = a A supply pressure supply pressure

Ps dimensionless supply pressure dimensionless supply pressure = ps / Pa, less dimensionless bearing swaying X, Y displacement dimensionless φ displacements of journal center of X and Y coordinates = my home, t bearing turbulent X, Y displacement Displacement of journal center of X and Y coordinates {q} bearing yaw X, Y displacement vector vector of displacements of

Journal center of X and Y coordinates = dq di d2q dr1 radius of journal radius of journal Su dimensionless sleeves rigid dimensionless stiffness ΊπΕΠζ bearing gang! I-stiffness coefficient coefficient = t time variable time 17 1250254 U-axis rotational speed journaling velocity V〇 orifice throttle speed orifice inlet velocity VP radial Darcy velocity field radial wave in radial κ direction w bearing rotor load capacity threshold load capacity of rotor mass =Mg W dimensionless bearing rotor load capacity dimensionless threshold load capacity of Rotor mass = iv / {2π RLpa)

x XY z Z circumferential coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate coordinate P β ε θ Φ Λ 流体 fluid density fluid density eccentricity ratio = e / C angle coordinate angular coordinate = z / and inclination angle attitude angle bearing parameter bearing number Λ = in. Throttle intake parameter

k } FT

24 purchase Q [2g. pJpaiC 18 1250254 λρ porous intake parameter porous feeding parameter ._ 12K ΤΉΖ ω axis rotation frequency rotation frequency of journal = fresh υ axis 榥 frequency whirl frequency of journal 7 axis 对 对 vs. rotation frequency ratio whirl To rotation frequency ratio - υ /ω τ virtual time variable imaginary time = /y ί same factory small W Variety. The intake parameters are respectively; = 1 (Γ4 and 2xl (T4. It can be seen that there are minimum and maximum values of rotor weight F under Λ=〇·j and 八=〇·5. It can be seen that the air bearing is at low speed (eight &lt;01) Or medium speed (Λ^ 〇5 = ' can withstand heavier rotor weights to bear the heavier rotor = 罝 also means to allow larger _ money rc hole bearings in the smaller intake gin == 10), can withstand The heavier rotor weighs under the larger intake parameter α.= 2 2 4 4: visible, ^ f\ ), the part can only bear lighter than the air intake parameter n-7 ίο By the = under the larger intake parameters (Λ:; two figures can be seen in the porous pumping 0.1) can withstand heavier turn; b) at / (four) speed (Λ &lt; two S.) 'at higher Rotating speed (the heart can bear the heavier 19 1250254 number Λ ΤΛ ! ! 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五 五Porous bearing money parameters / mesh ^ Figure = the fifth figure can be seen, the 5 rows of orifice bearings at a small speed = see, .Hr bears a heavier rotor weight. (5) in the sixth picture can be heavier bearing At a speed of * (λ = g · 5) ' The rotor weight ρ of the bearing = can be Wei at the same time, for each axis j' of different shape j exists - the optimal intake parameter value λ. Or; U, appears here: the maximum value of the bearing rotor I f. It is possible to tolerate a large, bearing eccentricity e without causing turbulence instability. As shown in the seventh to fourteenth drawings, it is shown that under the majority of bearings Λ = 〇 · 5, the rigidity of the bearing & (stiffness) and resistance, coefficient square (damping coefficient) relative to the orifice throttle = parameter λ. and porous bearing intake parameters; U changes. Generally 5, a larger stiffness &amp; value can be generated Larger load capacity; a larger damping coefficient can be seen to produce a more stable situation. From the seventh and tenth figures, it can be seen that the '5-row orifice bearing and the porous surface bearing produce a large negative diagonal stiffness coefficient. And diagonal stiffness, so as to produce a large load capacity. However, it can be seen from the eleventh figure that the diagonal damping coefficient 11 (diagonal damping e〇efficient) with the intake parameters λ and λρ Increase and change from negative to positive. Damping coefficient and ! In the sixth figure, the bearing can withstand the maximum rotor weight F with the increase of the intake parameter λ. and λρ by the maximum value, and it can be found that the 5 rows of orifice bearings can produce the maximum positive damping coefficient. This makes the 20 1250254 bearing can withstand the maximum rotor weight F sharply decreasing, β qualitatively deteriorates. It can also be found that the small and positive value of the tiger, as well as the negative and the 2 value, can produce a better bearing in the first sleeve. The large rotor is visible in the turret, and the fifteenth figure shows the maximum turbulent frequency versus the rotational frequency of the bearing parameter Λ = 〇 · 5 τ. The bearing J Cheng II T = Vhirl frequency rati °) relative to the orifice section k intake parameter; I. And the change in the intake parameters of the porous bearing eight. The maximum frequency ratio γ of the 5 rows of orifice bearings and the porous bearing can be seen along with the intake parameter λ. And λρ^ increases and increases; but the maximum freshness of the orifice orifice is better than the intake parameter λ. It becomes smaller and smaller. At the same time, it can be found in the sixth figure that the higher maximum frequency h is relatively less than the maximum acceptable rotor weight. It can be found in the seventh and tenth figures that the higher maximum frequency ratio r produces a larger negative and exempt value; and in the tenth-graph, it can be found that the higher maximum frequency ratio makes the damping coefficient and the value 1 Change from negative to rapid. The above stiffness coefficient and the change of the damping coefficient argon are not conducive to the stability of the bearing, so that the bearing can withstand the maximum rotor weight 1 sharp drop, as shown in the sixth figure. Figure 16 shows the intake air parameter λ at the orifice U. = 1〇-4 and multi-porous bearing intake parameters λρ = 1〇-7 and 1〇-8, the maximum frequency ratio 7 is relative to the bearing parameter Λ. When Λ = 〇1, a maximum value of the maximum frequency ratio r occurs. As can be seen from the third figure, this maximum value corresponds exactly to the minimum value of the maximum rotor weight of the party. At the same time, it can be found that the maximum frequency ratio r of the porous bearing decreases as the bearing parameter Λ increases. At the same time, it can be seen from the third figure that in the area of Λ&lt;〇.丨, 1250254 c: in the higher maximum frequency ratio. From this result, it is known that many of them have a good turn and a good stability. At the same time, by the first! ^ at low speed, there are more than the flow hole bearing at the middle speed (Λ% to find that 5 rows of sections have been stabilized by more rows of orifices. The following points are about the mixed popularity: Two bearings and porous bearings, Conclusion: The air is difficult to design. The porous bearing is under low rotation (the movement has a high stability. Therefore, it can withstand the maximum frequency ratio of :::: Three =; 2.5 in =^: °, 5) and low intake parameters ". = about, higher stability. The bearing can be known for the 3D full-pressure air air intake for the rotor of the rotating shaft. The weight of the rotor F is extremely high, and the bearing can withstand up to 0.5). Is the value of its characteristics (Λ = (3) and the maximum value (the heart is known. This can be the largest rotor weight in the third and fourth figures, just beginning to increase with the hole, and reach the hl mass bearing intake parameters again The increase continues to increase and can withstand == value. Then the change with the intake parameter is due to the rapid decrease of the weight of the greater trochanter. It increases as the enthalpy increases; And λ. And; U increase = bearing damping coefficient with the intake parameter is small. Therefore, the rigidity and damping of the bearing 22 1250254

System, which = interaction τ, produces - the optimal intake parameter value again. Or A P appears - can withstand the maximum value of the rotor weight F. Beyond this, the optimal intake parameter value is succumbing to the maximum rotor weight F. &gt; confusing &gt; 1 air neck bearing has the advantage that there are better bearing miscellaneous at low speed. This article explores the age of the rotor, which helps the designer to understand its characteristics, and the needle_承之(4) is the best design. In summary, the embodiments of the present invention can achieve the expected use efficiency 'and the specific structure disclosed therein' has not been seen in similar products, nor has it been disclosed before the application, and has fully complied with the provisions of the Patent Law. And the request, the application for the invention of a patent in accordance with the law, please forgive the review, and grant the patent, it is really sensible.月^ 23 1250254 [Simple description of the drawing] First figure · Schematic diagram of the radial bearing of the multi-row orifice bearing of the present invention, FIG. 2: Schematic diagram of the radial bearing of the porous bearing. Second figure: The maximum rotor weight f of the present invention ( Threshold load capacity of rotor mass) relative to the bearing parameter Λ (bearing number) (orifice throttle intake parameter λ 〇 = 1〇·4) Fourth: the maximum rotor weight F of the invention (threshold load capacity of rotor Mass) relative to the bearing parameter Λ φ (bearing number) change (orifice throttle intake parameter λ 〇 = 2 &gt; 1 (Γ 4) fifth figure: the greater rotor weight y of the present invention relative to the orifice throttle Gas parameter and the change pattern of the porous bearing intake parameter λ ρ (bearing parameter Λ = 0·1). Fig. 6: The maximum rotor weight F of the present invention is relative to the orifice throttled intake parameter λ. and the porous bearing The change pattern of the intake parameter λ ρ (bearing parameter Λ = 0.5) _ The seventh figure · The rigidity of the bearing of the invention 5\i (stiffness) relative to the orifice throttle intake parameter λ. And the porous bearing intake parameters ρ change (sucking parameter Λ = 0· 5 ) : The stiffness A of the bearing of the present invention is relative to the orifice throttle intake parameter; I. and the change of the porous bearing intake parameter λ ( (bearing parameter Λ = 0·5) ninth: the rigidity of the bearing of the present invention Stiffness relative to the orifice throttle intake parameter λ. and porous bearing intake parameter 24 1250254 into p change (bearing parameter Λ = 0·5) Tenth: the rigidity of the bearing of the invention is not 2 (stiffness The throttle parameter is compared with the orifice; I. and the porous bearing intake parameter; the change of U (bearing parameter Λ = 0/5) Η--Figure: Damping coefficient of the bearing of the present invention The change in the intake air parameter λ relative to the orifice and the change in the intake parameter λ ρ of the porous bearing (bearing parameter Λ = 0 · 5) Fig. 12: The damping coefficient of the invention and the damping coefficient of 2 (damping φ coefficient) The inlet throttle parameter λ and the change of the porous Hancheng intake parameter λΡ (Baicheng parameter Λ = 0·5) The thirteenth figure · The damping coefficient of the bearing of the invention and the damping coefficient of the bearing relative to the hole The mouth throttle intake parameter λ. and the porous bearing intake parameter λ Ρ change (Bearing parameters Λ = 0 · 5) FIG XIV: Wan damping bearing of the present invention 22 (damping φ coefficient) with respect to the intake orifice restrictor parameter λ. And the change of the intake parameter λ ρ of the porous bearing (bearing parameter Λ = 0· 5). Figure 15: The ratio of the maximum turbulent frequency to the rotational frequency of the bearing of the present invention (threshold whirl frequency ratio) is relative to The orifice throttles the intake parameter λ. And porous bearing intake parameters; U changes (bearing parameters Λ = 0 · ) 5 25 1250254 Figure 16: The maximum frequency ratio r of the invention is relative to the bearing parameter Λ (orificate throttle intake parameters; I = 1 (Γ4 and porous bearing intake parameters; U = 1〇-7 and 1〇_8) [Main component symbol description] (1) Bearing (11) Throttle (2) Porous bearing

26

Claims (1)

1250254 X. Patent application scope: An optimal stability mixed gas bearing design, mainly in the center of the bearing, equidistant from the axial section, symmetrically arranged with five rows of orifices, the number of orifices per row shall not be Less than 8 holes, evenly distributed on the circumference, the shape of the orifice can be a segmented hole, at medium speed (0.4 &lt; eight &lt; 0.8), and at low intake air (1. = 1 〇-4), the highest stability, in order to get the best stability. 27