Abstract:
A process for manufacturing components of gas turbine engine combustors, including the steps of performing a plurality of forming steps on a workpiece of a designated material to produce a combustor component of desired size and shape without exceeding a forming limit of the designated material, the forming steps being performed without any intermediate heat treatment on the workpiece.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates generally to a deflector plate in a gas turbine engine combustor and, in particular, to a process for manufacturing such deflector plates which does not include heat treatment of the workpiece between forming steps. 
     It is well known in the art for deflectors of gas turbine engine combustors to be manufactured by forming and trimming sheet metal material to a desired final part. During these forming processes, however, the workpiece deflector can exhibit excessive thinning or tearing. In order to avoid this defect, heat treatments or annealing steps have been performed between and after such forming steps. This is particularly applicable for parts manufactured out of Haynes® 188, a commonly used sheet metal material for gas turbine engine combustors due to its exposure to high temperatures. 
     Heat treatment of the deflector workpiece is not without its own disadvantages. Besides the time and expense of performing the heat treatment, typically by means of vacuum furnace equipment, it has been found to cause critical grain growth in the workpiece. Additionally, such heat treatment can cause the creation of a surface oxide layer which is detrimental to the subsequent brazing of such deflector to other combustor components. Thus, chemical treatment for removal of the oxide layer is oftentimes required prior to the brazing process. 
     In light of the foregoing, it would be desirable for an improved process of manufacturing combustor deflector plates to be developed which eliminates the need for heat treatment between forming steps without the workpiece incurring excessive thinning or cracking. It would also be desirable for such process to produce combustor deflector plates which have a finer grain size and more uniform structure, while still reducing the time and cost required as compared to current methods. 
     BRIEF SUMMARY OF THE INVENTION 
     In an exemplary embodiment of the invention, a process for manufacturing components of gas turbine engine combustors is disclosed as performing a plurality of forming steps on a workpiece of a designated material to produce a combustor component of desired size and shape without exceeding a forming limit of the designated material, the forming steps being performed without any intermediate heat treatment on the workpiece. 
     In a second embodiment of the present invention, a deflector plate for a gas turbine engine combustor is disclosed as including a substantially ring-shaped central portion providing an opening through the deflector plate, a flange portion encircling the central portion, and a shoulder portion serving as a junction of the central and flange portions, wherein heat treatment of the deflector plate has been eliminated during forming so as to obtain a grain size along said central portion within a range of approximately ASTM 7.5-9.5 after a braze material is sintered thereto. 
     In a third embodiment of the present invention, a method of developing a sequence of steps for a process of manufacturing a gas turbine engine combustor component is disclosed, wherein heat treatment between forming steps of a workpiece is eliminated. This method includes the following steps: developing a finite element analysis model of the manufacturing process, wherein deformation and thinning of the workpiece are represented during the forming steps; creating a user interface for entering a plurality of parameters associated with the manufacturing process; automatically creating a finite element analysis input file from the user interface parameters; determining the likelihood of a tearing defect occurring for the workpiece during the manufacturing process from each input file; and, establishing a sequence of forming steps for the manufacturing process which produce a combustor component conforming to a predetermined shape and size within a predetermined risk of tearing defects. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a deflector plate made in accordance with the process of the present invention; 
     FIG. 2 is a schematic cross-sectional view of an initial state of a workpiece subject to the process of the present invention; 
     FIG. 3 is a schematic cross-sectional view of a first forming step on the workpiece of FIG. 2 according to the process of the present invention; 
     FIG. 4 is a schematic cross-sectional view of a second forming step on the workpiece of FIG. 3 according to the process of the present invention; 
     FIG. 5 is a schematic cross-sectional view of the workpiece of FIG. 4 after a piercing step according to the process of the present invention has been performed; 
     FIG. 6 is a schematic cross-sectional view of a final forming step on the workpiece of FIG. 5 according to the process of the present invention; and, 
     FIG. 7 is a schematic cross-sectional view of a final trimming step on the workpiece of FIG. 6 according to the process of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings in detail, wherein identical numerals indicate the same elements throughout the figures, FIG. 1 depicts a deflector plate utilized in gas turbine engine combustors as being represented generally by reference numeral  10 . It will be seen therefrom that deflector plate  10  is of substantially symmetrical design and includes a longitudinal axis  12  passing therethrough. More specifically, deflector plate  10  has a central opening  14  formed therein by a substantially ring-shaped annular wall  16 , a flange portion  18  which is angled away from and encircles annular wall  16 , and a shoulder region  20  connecting annular wall  16  and flange portion  18  having a desired radius R. Further, a plurality of cooling holes  22  are formed within shoulder region  20 . 
     It will be appreciated that the present invention involves a novel process for manufacturing deflector plate  10  which may also be applied to other gas turbine engine combustor components exposed to high temperatures and made of a sheet metal material. The various steps of the process are depicted in FIGS. 2-7 and are now described in greater detail. Initially, a workpiece  50  is shown as a flat blank of material held next to a die  60  by hydraulic pressure so as to be adjacent a punch  70  (see FIG.  2 ). Workpiece  50  is formed (preferably by hydroforming) into an axisymmetric shape (see FIG. 3) of desired size and shape, where workpiece  50  includes a substantially cylindrical central portion  52  punched therein having an initial diameter D 1 , a substantially flat flange portion  54  encircling central portion  52 , and a transition region  56  between central portion  52  and flange portion  54 . It will be noted that transition region  56  is initially formed with a radius R 1  therein. Punch  70  also has a nose radius N 1  located at each corner thereof in order to lessen the stress imposed on workpiece  50 . 
     Although not depicted in FIG. 3, it is preferred that the aforementioned hydroforming step be accomplished in multiple stages. More specifically, a first punch motion is provided by punch  70  for a first predetermined displacement while workpiece  50  is under a first predetermined pressure. Thereafter, at least a second punch motion is performed by punch  70  for a second predetermined displacement while workpiece  50  is under a second predetermined pressure. 
     Next, as depicted in FIG. 4, workpiece  50  is held against a second die  65  so that a second punch  75  (having a nose radius N 2  at each corner) is able to form modifications thereto. In this step, central portion  52  is given a larger diameter D 2  by punch  75 , flange portion  54  is bent so as to be angled further away from central portion  52  (identified by an angle θ), and transition region  56  has a smaller radius R 2  in accordance with die  65 . It will be appreciated that conventional manufacturing processes require some kind of heat treatment for workpiece  50  between the forming steps described with respect to FIGS. 3 and 4, but none is required by the process of the present invention. 
     According to FIG. 5, workpiece  50  undergoes a piercing operation where a substantially circular end  57  of central cylindrical portion  52  is removed so as to provide central opening  14  described hereinabove for deflector plate  10 . At this point, central portion  52  becomes a substantially ring-shaped annular wall  58 . Workpiece  50  is preferably then subjected to a final forming step (see FIG. 6) by a die  67  and a punch  77  to place it in accordance with the final dimensions for deflector plate  10 . It will also be seen that a blankholder  80  is utilized to hold workpiece  50  against die  67  and prevent workpiece  50  from drawing in toward punch  77 . More specifically, this forming step preferably involves increasing the diameter of annular wall  58  of central portion  52  via punch  77 , straightening annular wall  58  by means of die  67  so as to be substantially vertical, and modifying radius R 2  of transition region  56  as necessary. The final step in forming workpiece  50  involves trimming a top portion of annular wall  58  which has been thinned from the previous steps so that the dimensional requirements of deflector plate  10  are met. 
     Once the foregoing steps have been performed, it will be appreciated that workpiece  50  will typically undergo several other operations to transform it into deflector plate  10  as described above. In particular, a plurality of spaced cooling holes (identified by the numeral  22  in FIG. 1) are provided along the radiused portion of transition region  56 , the outline of flange portion  54  is trimmed, and a brazing process is performed thereon. With respect to the brazing process, this is typically accomplished by attaching a brazing material tape to workpiece  50  along an inner diameter D 2  of annular wall  58  (where as a deflector plate  10  it will be connected to the remainder of a gas turbine engine combustor structure). The brazing tape preferably consists of braze material spherical particles in an aggregate with an organic bonding material. After the brazing tape is attached, a vacuum heat treatment process follows where workpiece  50  is soaked at a temperature of 2025° F. for approximately five minutes, and thereafter vacuum and air cooled. In this way, the material of the brazing tape is sintered to workpiece  50 . Of course, it will be understood that workpiece  50  (as deflector plate  10 ) is heat treated again in order to create a brazing joint when connected to the combustor structure (preferably at 2140° F. for approximately five minutes). 
     By eliminating the heat treatment operations on workpiece  50  during the forming steps, it has been found that besides reducing the time and expense of the manufacturing process, the deflector plates manufactured therefrom are of a higher quality when compared to those produced by conventional methods. In this regard, the microstructure of deflector plates made according to the inventive process described herein exhibits a fine grain size (ASTM 7.5-9.5) and is relatively uniform after the sintering process. This stems from workpiece  50  being subjected to temperatures during the forming steps which are less than those during the sintering step. Even after the final heat treatment cycle when workpiece  50  is brazed to a combustor, the microstructure thereof was found to be in the range of ASTM 6.5-8.5 for the present process as opposed to ASTM 1-8 for conventional methods. It will be appreciated that the finer grain size of the deflector plates produced by the present process is desirable due to its inherent characteristics of increased strength and intergranular crack growth resistance. 
     It will be appreciated that various processes exist for designing a manufacturing process, including that disclosed in a patent application entitled “Method And Apparatus For Designing A Manufacturing Process For Sheet Metal Parts,” having Ser. No. 09/017,343, filed Feb. 2, 1998, which is owned by the assignee of the present invention and hereby incorporated by reference. In order to design the steps of the present process of manufacturing a deflector plate without intermediate heat treatment steps, a simplified axisymmetric finite element analysis model of the process was developed. While a three-dimensional method could be utilized for the finite element analysis, it was found to be time consuming. Accordingly, the simplified model uses an 8-node reduced integration continuum element which was capable of representing deformation and thinning of workpiece  50  during successive forming steps. 
     A spreadsheet (based on the Excel® software program from Microsoft) was also created for the generation of input files to be used in the finite element analysis. This spreadsheet contains a user interface where all the geometry parameters of the forming tools (i.e., dies  60 ,  65  and  67  and punches  70 ,  75  and  77 ), as well as other process parameters, are entered so as to automatically create a finite element analysis input file. More specifically, the parameters entered into the spreadsheet include: stock thickness (inches) of the initial blank of material; blank diameter (inches) of workpiece  50 ; diameter (inches) of hydroform punch  70 ; nose radius N 1  (inches) of hydroform punch  70 ; first pressure (psi) of hydroform during a first punch motion; displacement (inches) of hydroform punch  70  during the first punch motion; second pressure (psi) of hydroform punch  70  during a second punch; displacement (inches) of hydroform punch  70  during the second punch; height of punch  75  (inches); nose radius N 2  (inches) of punch  75 ; radius R 1  of transition region  56  (inches), otherwise known as the draw radius for die  65 ; diameter D 2  (inches) of die  65 ; angle θ (degrees) of die  65 ; gap (inches) between punch  75  and die  65  (approximately the thickness of workpiece  50 ); number of elements to trim from center portion  52 ; height (inches) of punch  75 ; nose radius N (inches) of punch  77 ; radius R 2  of transition region  56  (inches), otherwise known as the draw radius of die  67 ; diameter (inches) of die  67 ; angle (degrees) of die  67 ; gap (inches) between punch  77  and die  67 ; pressure (psi) of blankholder  80 ; and, number of elements to trim from flange portion  54 . 
     It will be appreciated that a program utilizing the Visual Basic programming language was used to create the finite element analysis input deck (an exemplary listing for such program is appended hereto). This program is used in conjunction with the spreadsheet user interface for the generation of an ABAQUS input file used in the simulations by the finite element analysis program. 
     The combination of the simplified finite element analysis model and the spreadsheet can be used on a trial and error basis or as part of a Design Of Experiments (DOE) process to develop the forming process sequence that produces a deflector plate (or other sheet metal part) free of tearing defects. The likelihood of a tearing defect occurrence can then be obtained by comparing the membrane strains of workpiece  50  (i.e., strains at the middle of the blank thickness) with a Forming Limit Diagram of the material. Thus, it will be appreciated that while this combination was used to design the manufacturing process of deflector plate  10  discussed herein, it may be applied to other sheet metal parts of gas turbine engine combustors in a similar manner. 
     Having shown and described the preferred embodiment of the present invention, further adaptations of the combustor deflector plate and the process for manufacturing it can be accomplished by appropriate modifications by one of ordinary skill in the art without departing from the scope of the invention. 
     
       
         
               
             
               
             
               
               
             
               
             
           
               
                 APPENDIX A 
               
               
                   
               
               
                 Visual Basic program used in conjunction with the Excel front end 
               
               
                 spreadsheet for the generation of an ABAQUS input file 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Option Explicit 
               
               
                 Public Sub check( ) 
               
               
                 Dim Ws_in, Ws_calc, Ws_out As Worksheet 
               
               
                 Dim i, marker As integer 
               
               
                 Dim fileSaveName As Variant 
               
               
                 Dim fileOrigName As Variant 
               
               
                 Dim save_it As Variant 
               
               
                 Dim outSheetNew As Variant 
               
               
                 Set Ws_in = Worksheets(“input”) 
               
               
                 Set Ws_calc = Worksheets(“input”) 
               
               
                 Set Ws_out = Worksheets(“deflector”) 
               
               
                 fileOrigName = ActiveWorkbook.FullName 
               
               
                 marker = 0 
               
               
                 ′get geometry for first form 
               
               
                 Sheets(“input”).Select 
               
               
                 Ws_calc.Cells(2, “Q”).Value = “First Form” 
               
               
                 Ws_calc.Cells(3, “T”).Value = “variables” 
               
               
                 Ws_calc.Cells(4, “T”).Value = “H1” 
               
               
                 Ws_calc.Cells(5, “T”).Value = “L1” 
               
               
                 Ws_calc.Cells(6, “T”).Value = “H3” 
               
               
                 Ws_calc.Cells(7, “T”).Value = “L3” 
               
               
                 Ws_calc.Cells(8, “T”).Value = “Theta3” 
               
               
                 Ws_calc.Cells(9. “T”).Value = “H” 
               
               
                 Ws_calc.Cells(11, “T”).Value = “constants” 
               
               
                 Ws_calc.Cells(12, “T”).Value = “L” 
               
               
                 Ws_calc.Cells(13, “T”).Value = “R” 
               
               
                 Ws_calc.Cells(14, “T”).Value = “Theta1” 
               
               
                 Ws_calc.Cells(15, “T”).Value = “H2” 
               
               
                 Ws_calc.Cells(4, “U”).Value = 1 
               
               
                 Ws_calc.Cells(5, “U”).Value = 1 
               
               
                 Ws_calc.Cells(6, “U”).Value = 1 
               
               
                 Ws_calc.Cells(7, “U”).Value = 1 
               
               
                 Ws_calc.Cells(8, “U”).Value = 1 
               
               
                 Ws_calc.Cells(9, “U”).Value = 1 
               
               
                 Ws_calc.Cells(12, “U”).Value = “= J5/2 − T33” 
               
               
                 Ws_calc.Cells(13, “U”).Value = “= J16” 
               
               
                 Ws_calc.Cells(14, “U”).Value = “= J18” 
               
               
                 Ws_calc.Cells(15, “U”).Value = 2.5 
               
               
                 Ws_calc.Cells(4, “Q”).Value = “tan(Theta1) = H1/L1” 
               
               
                 Ws_calc.Cells(5, “Q”).Value = “= TAN(U14*PI( )/180)” 
               
               
                 Ws_calc.Cells(5, “R”).Value = “= U4/U5” 
               
               
                 Ws_calc.Cells(6, “Q”).Value = “Theta1 + Theta3 = 90” 
               
               
                 Ws_calc.Cells(7, “Q”).Value = “= U14 + U8” 
               
               
                 Ws_calc.Cells(7, “R”).Value = “= 90” 
               
               
                 Ws_calc.Cells(8, “Q”).Value = “H3 = R*Sin(Theta3)” 
               
               
                 Ws_calc.Cells(9, “Q”).Value = “= U6” 
               
               
                 Ws_calc.Cells(9, “R”).Value = “= U13*SIN(U8*PI( )/180)” 
               
               
                 Ws_calc.Cells(10, “Q”).Value = “L3 = R*Cos(Theta3)” 
               
               
                 Ws_calc.Cells(11, “Q”).Value = “= U7” 
               
               
                 Ws_calc.Cells(11, “R”).Value = “= U13*COS(U8*PI( )/180)” 
               
               
                 Ws_calc.Cells(12, “Q”).Value = “L = R − L3 + L1” 
               
               
                 Ws_calc.Cells(13, “Q”).Value = “= U12” 
               
               
                 Ws_calc.Cells(13, “R”).Value = “= U13 − U7 + U5” 
               
               
                 Ws_calc.Cells(14, “Q”).Value = “H = H1 + H3” 
               
               
                 Ws_calc.Cells(15, “Q”).Value = “= U9” 
               
               
                 Ws_calc.Cells(14, “R”).Value = “= U4 + U6” 
               
               
                 ′punch movement 
               
               
                 Ws_calc.Cells(3, “X”).Value = “Punch movement stuff” 
               
               
                 Ws_calc.Cells(4, “X”).Value = “gap{circumflex over ( )}2+d{circumflex over ( )}2=f{circumflex over ( )}2” 
               
               
                 Ws_calc.Cells(5, “X”).Value = “=AB12{circumflex over ( )}2+AB4{circumflex over ( )}2” 
               
               
                 Ws_calc.Cells(5, “Y”).Value = “= AB5{circumflex over ( )}2” 
               
               
                 Ws_calc.Cells(6, “X“).Value = “f=t/cos(phi1)” 
               
               
                 Ws_calc.Cells(7, “X”).Value = “=AB5” 
               
               
                 Ws_calc.Cells(7, “Y”).Value = “=AB13/COS(AB6*PI( )/180)” 
               
               
                 Ws_calc.Cells(8, “X”).Value = “tan(phi2)=d/gap” 
               
               
                 Ws_calc.Cells(9, “X”).Value = “=TAN(AB7*PI( )/180)” 
               
               
                 Ws_calc.Cells(9, “Y”).Value = “=AB4/AB12” 
               
               
                 Ws_calc.Cells(10, “X”).Value = “90=theta+phi1+phi2” 
               
               
                 Ws_calc.Cells(11, “X”).Value = “90” 
               
               
                 Ws_calc.Cells(11, “Y”).Value = “=AB14+AB6+AB7” 
               
               
                 Ws_calc.Cells(4, “AB”).Value = “1” 
               
               
                 Ws_calc.Cells(5, “AB”).Value = “1” 
               
               
                 Ws_calc.Cells(6, “AB”).Value = “1” 
               
               
                 Ws_calc.Cells(7, “AB”).Value = “1” 
               
               
                 Ws_calc.Cells(12, “AB”).Value = “=J19” 
               
               
                 Ws_calc.Cells(13, “AB”).Value = “=J4” 
               
               
                 Ws_calc.Cells(14, “AB”).Value = “=J18” 
               
               
                 ′under tools —&gt; references, make sure solver.xla is checked 
               
               
                 Solverreset 
               
               
                 SolverOptions precision:=0.001 
               
               
                 SolverOK setcell:=Range(“Q7”),  —   
               
               
                  maxminval:=3,  —   
               
               
                  valueof:=90,  —   
               
               
                  bychange:=Range(“U4:U9”) 
               
               
                 Solveradd cellref:=Range(“R5”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Q5”) 
               
               
                 Solveradd cellref:=Range(“R9”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Q9”) 
               
               
                 Solveradd cellref:=Range(“R11”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Q11”) 
               
               
                 Solveradd cellref:=Range(“R13”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Q13”) 
               
               
                 Solveradd cellref:=Range(“R15”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Q15”) 
               
               
                 Solveradd cellref:=Range(“U4:U9”),  —   
               
               
                  relation:=3,  —   
               
               
                  formulatext:=0 
               
               
                 Solversolve ′userFinish:=True 
               
               
                 Solverreset 
               
               
                 SolverOptions precison:=0.001 
               
               
                 SolverOK setcell:=Range(“Y11”),  —   
               
               
                  maxminval:=3,  —   
               
               
                  valueof:=90,  —   
               
               
                  bychange:=Range(“AB4:AB7”) 
               
               
                 Solveradd cellref:=Range(“X5”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Y5”) 
               
               
                 Solveradd cellref:=Range(“X7”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Y7”),  —   
               
               
                 Solveradd cellref:=Range(“X9”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Y9”) 
               
               
                 Sovlersolve ′userFinish:=True 
               
               
                 Ws_calc.Cells(18, “Q”).Value = “Final Form” 
               
               
                 Ws_calc.Cells(19, “T”).Value = “variables” 
               
               
                 Ws_calc.Cells(20, “T”).Value = “H1” 
               
               
                 Ws_calc.Cells(21, “T”).Value = “L1” 
               
               
                 Ws_calc.Cells(22, “T”).Value = “H3” 
               
               
                 Ws_calc.Cells(23, “T”).Value = “L3” 
               
               
                 Ws_calc.Cells(24, “T”).Value = “Theta3” 
               
               
                 Ws_calc.Cells(25, “T”).Value = “H” 
               
               
                 Ws_calc.Cells(27, “T”).Value = “constants” 
               
               
                 Ws_calc.Cells(28, “T”).Value = “L” 
               
               
                 Ws_calc.Cells(29, “T”).Value = “R” 
               
               
                 Ws_calc.Cells(30, “T”).Value = “Theta1” 
               
               
                 Ws_calc.Cells(31, “T”).Value = “H2” 
               
               
                 Ws_calc.Cells(20, “U”).Value = 1 
               
               
                 Ws_calc.Cells(21, “U”).Value = 1 
               
               
                 Ws_calc.Cells(22, “U”).Value = 1 
               
               
                 Ws_calc.Cells(23, “U”).Value = 1 
               
               
                 Ws_calc.Cells(24, “U”).Value = 1 
               
               
                 Ws_calc.Cells(25, “U”).Value = 1 
               
               
                 Ws_calc.Cells(28, “U”).Value = “= J5/2 − T35” 
               
               
                 Ws_calc.Cells(29, “U”).Value = “= J23” 
               
               
                 Ws_calc.Cells(30, “U”).Value = “= J25” 
               
               
                 Ws_calc.Cells(31, “U”).Value = 2.5 
               
               
                 Ws_calc.Cells(20, “Q”).Value = “tan(Theta1) = H1/L1” 
               
               
                 Ws_calc.Cells(21, “Q”).Value = “= TAN(U30*PI( )/180)” 
               
               
                 Ws_calc.Cells(21, “R”).Value = “= U20/U21” 
               
               
                 Ws_calc.Cells(22, “Q”).Value = “Theta1 + Theta3 = 90” 
               
               
                 Ws_calc.Cells(23, “Q”).Value = “= U30 + U24” 
               
               
                 Ws_calc.Cells(23, “R”).Value = “= 90” 
               
               
                 Ws_calc.Cells(24, “Q”).Value = “H3 = R*Sin(Theta3)” 
               
               
                 Ws_calc.Cells(25, “Q”).Value = “= U22” 
               
               
                 Ws_calc.Cells(25, “R”).Value = “= U29*SIN(U24*PI( )/180)* 
               
               
                 Ws_calc.Cells(26, “Q”).Value = “L3 = R*Cos(Theta3)” 
               
               
                 Ws_calc.Cells(27, “Q”).Value = “= U23” 
               
               
                 Ws_calc.Cells(27, “R”).Value = “= U29*COS(U24*PI( )/180)” 
               
               
                 Ws_calc.Cells(28, “Q”).Value = “L = R − L3 + L1” 
               
               
                 Ws_calc.Cells(29, “Q”).Value = “= U28” 
               
               
                 Ws_calc.Cells(29, “R”).Value = “= U29 − U23 + U21” 
               
               
                 Ws_calc.Cells(30, “Q”).Value = “H = H1 + H3” 
               
               
                 Ws_calc.Cells(31, “Q”).Value = “= U25” 
               
               
                 Ws_calc.Cells(31, “R”).Value = “= U20 + U22” 
               
               
                 ′under tools —&gt; references, make sure solver.xla is checked 
               
               
                 Solverreset 
               
               
                 SolverOptions precison:=0.001 
               
               
                 SolverOK setcell:=Range(“Q23”),  —   
               
               
                  maxminval:=3,  —   
               
               
                  valueof:=90,  —   
               
               
                  bychange:=Range(“U20:U25”) 
               
               
                 Solveradd cellref:=Range(“R21”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Q21”) 
               
               
                 Solveradd cellref:=Range(“R25”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Q25”) 
               
               
                 Solveradd cellref:=Range(“R27”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Q27”) 
               
               
                 Solveradd cellref:=Range(“R29”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Q29”) 
               
               
                 Solveradd cellref:=Range(“R31”),  —   
               
               
                  relation:=2,  —   
               
               
                  formulatext:=Range(“Q31”) 
               
               
                 Solveradd cellref:=Range(“U20:U25”),  —   
               
               
                  relation:=3,  —   
               
               
                  formulatext:=0 
               
               
                 Solversolve ′userFinish:=True 
               
               
                 Worksheets(“input”).Activate 
               
               
                 ′If marker = 1 Then 
               
               
                 ′ MsgBox “Please check your inputs. Incompatibilities highlighted in red or error 
               
               
                 number given.” 
               
               
                 ′Else 
               
               
                  ′Display message, title, and default value. 
               
               
                  fileSaveName = Application.GetSaveAsFilename(  —   
               
               
                   fileFilter:=“Text Files(*.inp), *.inp”) 
               
               
                  If fileSaveName &lt;&gt; False Then 
               
               
                   save_it = MsgBox(“Save as ” &amp; fileSaveName, vbOKCancel, “save”) 
               
               
                   If save_it = vbOK Then 
               
             
          
           
               
                   
                 Worksheets(“deflector”).Activate 
               
               
                   
                 ActivateSheet.SaveAs filename:=fileSaveName, FileFormat:=xlTextPrinter 
               
               
                   
                 outSheetNew = ActiveSheet.Name 
               
               
                   
                 Sheets(outSheetNew).Select 
               
               
                   
                 Sheets(outSheetNew).Name = “deflector” 
               
               
                   
                 Application.DisplayAlerts = False 
               
               
                   
                 ActiveWorkbook.SaveAs filename:=fileOrigName, FileFormat:=xlNormal 
               
               
                   
                 Application.DisplayAlerts = True 
               
             
          
           
               
                   End If 
               
               
                  End If 
               
               
                 ′End If 
               
               
                  Worksheets(“input”).Activate 
               
               
                 End Sub