Subject: Forces on the 19cm endcaps ~ as the forces on the 30 cm endcaps From: Kin Yip To: "Hock, Jonathan" CC: "Mills, James A" , "Meng, Wuzheng" References: Message-ID: <4b511fc2-325e-5d89-1640-cddbfa3a8db2@bnl.gov> Date: Wed, 11 Apr 2018 15:38:52 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 In-Reply-To: Content-Type: multipart/alternative; boundary="------------B94A8588A55979667AF309F9" Content-Language: en-US MIME-Version: 1.0 --------------B94A8588A55979667AF309F9 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: quoted-printable Hi Jon, I've just gone back to the 19cm end-cap models (that I modified from=20 Wuzheng's a year ago with Nick's demo).=C2=A0=C2=A0 The forces on these 19 = cm=20 end-caps seem to be about the same as those thicker 30 cm end-cap models. The Non-Lead end is at=C2=A0 z >0 whereas the Lead end (the side with=20 Extension/Valvebox hole) is at z<0.=C2=A0=C2=A0 The forces along z-coordina= te are=20 in general towards the center of the Magnet Coil, so the force for the end-cap at=20 z>0 is -ve and vice versa.=C2=A0=C2=A0=C2=A0 +ve y points to the sky (upwar= ds) and the=20 coordinate system is obeying right-handed rule. I've used the same "Virtual Work" method in Opera and the forces in=20 Newton are as follows : Forces in N (on the Endcap in the Lead-End): Forces in N: =C2=A0x-direction: 274.593238356028 =C2=A0y-direction: 377.585029633337 =C2=A0z-direction: 225550.657308196 Forces in N (on the Endcap in the Non-Lead-End) : =C2=A0x-direction: 3.99631782131473 =C2=A0y-direction: -254.841736182178 =C2=A0z-direction: -221729.434566932 [=C2=A0 All these are magnetic forces, not including weight :-)=C2=A0 ]=C2= =A0=C2=A0=C2=A0 If you=20 like, you can compare the nos. with the nos. below for the 30cm endcap=20 model that I gave Jim and Steve on Feb. 16, 2018.=C2=A0=C2=A0 They're about the s= ame. Also, as you've asked me and I've checked, the gap between the central=20 HCAL and the poletip is 15 cm in Wuzheng's model (from +/- 315.81 cm to +/-=C2=A0 330.81 cm).=C2=A0 When making the poletip thinner a year ago, = I've=20 been careful to keep this gap distance the same and only change the outermost/furthermost z to reduce thickness. Kin On 02/16/2018 11:38 PM, Yip, Kin wrote: > > Hi Jim, > > I used Wuzheng=E2=80=99s sPHENIX 3D model to calculate the total force on= the=20 > end caps and the following are the results : > > Forces in N (on the Endcap in the Lead-End --- the side with Valvebox=20 > which has an additional rectangular hole): > > x-direction: 252.170734026629 > > =C2=A0y-direction: 374.422526190712 > > =C2=A0z-direction: 224897.36184526 > > Forces in N (on the Endcap in the Non-Lead-End) : > > x-direction: 15.9218665419685 > > =C2=A0y-direction: -250.296836993461 > > =C2=A0z-direction: -221035.947391377 > > In Opera, =C2=A0there are two methods and the above is from one of the=20 > methods, which seems to be slightly higher than > > the other method in Fz (by 7-8%). > > Kin > --------------B94A8588A55979667AF309F9 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable Hi Jon,

I've just gone back to the 19cm end-cap models (that I modified from Wuzheng's a year ago with Nick's demo).   The forces o= n these 19 cm end-caps seem
to be about the same as those thicker 30 cm end-cap models.

The Non-Lead end is at z >0 whereas the Lead end (the side with Extension/Valvebox hole) is at z<0.   The forces al= ong z-coordinate are in general
towards the center of the Magnet Coil, so the force for the end-cap at z>0 is -ve and vice versa.    +ve y = points to the sky (upwards) and the coordinate system
is obeying right-handed rule.

I've used the same "Virtual Work" method in Opera and the f= orces in Newton are as follows :

Forces in N (on the Endcap in the Lead-End):
Forces in N:
x-direction: 274.593238356028
y-direction: 377.585029633337
z-direction: 225550.657308196

Forces in N (on the Endcap in the Non-Lead-End) :
x-direction: 3.99631782131473
y-direction: -254.841736182178
z-direction: -221729.434566932

[ All these are magnetic forces, not including weight :-) ]  &nbs= p; If you like, you can compare the nos. with the nos. below for the 30cm endcap model
that I gave Jim and Steve on Feb. 16, 2018.   They're a= bout the same.

Also, as you've asked me and I've checked, the gap between the central HCAL and the poletip is 15 cm in Wuzheng's model (from +/- 315.81 cm
to +/- 330.81 cm). When making the poletip thinne= r a year ago, I've been careful to keep this gap distance the same and only change the
outermost/furthermost z to reduce thickness.

Kin

On 02/16/2018 11:38 PM, Yip, Kin wrote:<= br>

=20

Hi Jim,

I used Wuzheng=E2=80=99s sPHENIX 3D model to calculate the total force on the end caps and the following are the results :

Forces in N (on the Endcap in the Lead-End --- the side with Valvebox which has an additional rectangular hole):

x-direction: 252.170734026629

y-direction: 374.422526190712 &nb= sp;

z-direction: 224897.36184526

Forces in N (on the Endcap in the Non-Lead-End) :

x-direction: 15.9218665419685 &nb= sp;

y-direction: -250.296836993461 &n= bsp;

z-direction: -221035.947391377

In Opera, there are two methods and th= e above is from one of the methods, which seems to be slightly higher than

the other method in Fz (by 7-8%). = ;

Kin

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