5.3.3.3. Tables

• The Mode Summary table is shown for every OM2p and OM3p simulation. It provides calculations of the mode characteristics for each mode in the simulation.

Mode Summary Parameters

Quantity

Expression

Units reported

Output By

Notes

Frequency

f

GHz

OM2p and OM3p

The resonant frequency of the extracted mode.

Voltage where ω = 2πf is the resonant radial frequency, β is the particle velocity (as a fraction of c) as predefined in the simulation properties dialog box (default value is 1), and c is the speed of light in vacuum.

Volts

(None)

Not output. The voltage is used to compute other quantities in the Mode Summary table. The integration path you defined in the simulation properties dialog box determines the axial direction z as well as the position of the integration in the transverse plane, indicated by (r, θ).

Energy where E is the electric field, is the relative permittivity tensor, and the integral is taken over the cavity volume.

Joules

OM2p and OM3p

Mode energy, or stored energy. The mode fields are always normalized so that this quantity is numerically equal to the free-space permittivity ε0.

Shunt impedance where Pl is the wall power loss, described as follows.

ohms

OM2p in RZ coordinates, and OM3p.

The shunt impedance is calculated over the shunt impedance integration path you predefined in the simulation properties dialog box.

Q total unitless

OM2p and OM3p

Total quality factor of the cavity.

Q wall loss where W is the mode energy, defined above, and Pl is the wall power loss defined as follows.

unitless

OM2p and OM3p

Q material where tan(δ) is the electric loss tangent.

unitless

OM2p and OM3p

Wall power loss where H is the magnetic field, and the integral is over all conducting surfaces.

Watts

OM2p and OM3p

Wall power loss is calculated over the surface of all electrical conductors in the geometry, where Rs is the conductor sheet resistance. For PEC, Rs is calculated based on the settings in the simulation setup dialog, in the Solver tab, under Power Loss Calculations.

R/Q ohms

OM2p in RZ coordinates, and OM3p.

Ratio of shunt impedance to quality factor.

Kick factor where W is the mode energy and L is the integration path length.

V/(C*m2)

OM2p in RZ coordinates, and OM3p.

The kick factor is calculated over the kick factor integration path you predefined in the simulation properties dialog box. Unlike the shunt impedance integration path, the kick factor integration path is typically defined slightly off-axis. In OM2p, the kick factor is only computed for RZ coordinate geometries where the azimuthal mode number is set to 1.

Peak E-field magnitude

E p

V/m

OM2p and OM3p

Peak electric field magnitude in the cavity. The location is also output.

Peak H-field magnitude

H p

A/m

OM2p and OM3p

Peak magnetic field magnitude in the cavity. The location is also output.

Peak surface E-field magnitude

E s

V/m

OM2p and OM3p

Peak electric field magnitude on a conducting surface. The location is also output.

Peak surface H-field magnitude

H s

A/m

OM2p and OM3p

Peak magnetic field magnitude on a conducting surface. The location is also output.

Peak axial electric field magnitude, on axis

E a

V/m

OM2p and OM3p

Peak axial electric field magnitude, on axis. The location is also output.

Peak axial magnetic field magnitude, on axis

H a

A/m

OM2p and OM3p

Peak axial magnetic field magnitude, on axis. The location is also output. V/m

OM2p in RZ coordinates, and OM3p.

The average acceleration gradient is found by calculating the voltage along the shunt impedance integration path, and dividing by the length of the path.

Ep/Eacc

unitless

OM2p in RZ coordinates, and OM3p.

Es/Eacc

unitless

OM2p in RZ coordinates, and OM3p.

Hs/Eacc

Siemens

OM2p in RZ coordinates, and OM3p.

Transit time factor unitless

OM2p in RZ coordinates, and OM3p.

The transit time factor is calculated over the shunt impedance integration path you predefined in the simulation properties dialog box.

Geometric factor where μ0 is the free space permeability, and σ is the bulk conductivity of the metal walls.

ohms

OM2p in RZ coordinates, and OM3p.

The geometric factor is independent of any material losses within the cavity. It depends only on the shape of the cavity and the losses in the metal walls of the cavity.

degrees

All problems with periodic boundaries.

In periodic problems, this shows the phase advance preset by the user in the simulation properties dialog box.

Power flow where Sm is the periodic master surface, and Ss is the periodic slave surface.

Watts

All problems with periodic boundaries.

In periodic problems, the power flow is the power that passes through the structure. It is calculated as the average of the power into the master surface and the power out of the slave surface.

Integration path length

L

centimeters

OM2p and OM3p

Effective length of the shunt impedance integration path, accounting for any clipping and symmetry in the geometry.

Symmetry volume fraction

unitless

OM2p and OM3p

In geometries with symmetry planes, this gives the fraction of the total structure that is included in the simulation.

• The Stored Energy By Material table displays stored electric and magnetic energy, by material.

• The Dispersion Curve table is only shown in simulations with periodicity, where a Periodic Master/ Periodic Slave pair of boundary conditions has been used. In such problems, the Dispersion Curve table shows the mode frequency as a function of phase advance.

All of the above results can be viewed by changing the Primary > Qualifier 3 parameter.

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