Peterburg Rocket Stove Calculations in Excel Format

[coisinger]

I have taken the Peterburg Calculations sheet and created an excel spreadsheet that allows input values.  This will calculate all values based primarily on the Heat Riser Diameter as the input value.  There is also an input to calculate the size of a primary opening based on 20% of the area of the Heat Riser.  It will allow you to configure a Width/Height that is suitable for your application.  I also convert Primary and Secondary air (P Channel Dimension) to Radius and Diameter dimensions depending on any particular build as well.  Results have been verified with the table in both SI and Metric units.

I'd like to share it, but I don't have a way to share an excel file?  

[coisinger]

Here is an 'rough' example of the format.  All values are calculated based on the formulas provided in the Peterburg Calculations.  Again, my thoughts on this where to allow a user to input a value that fit their needs.  I am designing a batch heater that will use an octagonal riser (see my profile picture), so I can get an area for that, an use an approximate diameter that will yeild the area "A" of that build and allow the spreadsheet to calculate the other variables.

Below is an example:

In my case the configuration of the insulated fire brick yields a cross-section area of 20.75 in sq (53548.04 mm sq) for the heat riser.  I input values until the number 5.14 in (130.56 mm) resulted in an area of 20.75 in sq. This then calculates throughout the spreadsheet for the other variables and values required.


Variable                                                       in                                               mm
Given Heat Riser Diameter = D = Diameter     D = 5.14      <---insert value          130.56 
                                              Width          W = 1.85                                        47.00 
                                              Area            A = 20.75  in sq                              53548.04 mm sq
                                                                      0.14  FT2                                  0.05 M2
VARIABLES:
B Base
W Width

                                                                 in             mm
Base B:          D x 0.72                                 3.70         94.00    
Riser Height:   B x 10                                   37.01       940.00    


Batch Box Dimensions:
Width:          B x 2                                       7.40         219.5
Height:         B x 3                                       11.10       329.2
Depth:          B x 4                                       14.80       438.9


Port Dimensions (Opening to Riser):
Width:          B / 2                                       1.85         54.9
Height:         B x 2.2                                    14.80         241.4


P-Channel Dimensions (Secondary Air):
Width:          B / 2                                       1.85          54.9         0.25 <---insert value   
Height (Thkns): ((3.14(d/2)^2)x0.05/W           0.56          16.6         4.15    
Area (sq in/sq mm): (WxH)                           1.04          911.6       1.04

A=pi x r2

solve r = (A / PI )^0.5                             R = 0.57 sq in           Diam = 1.34 sq in
                                                            R = 370.66 sq mm     Diam = 740.32 sq mm

***(Note: I plan to incorporate two vertical slots to introduce primary air at the door to the firebox. I've considered introducing that air via a tube. This is why I solve for 'r' radius to get the area required.)

Primary Air (20% of the x-sectional riser area)
Areax20%:      A x 0.20                              4.15             2677.40
                                     
Width: 0.50 <---insert value
Height: 8.30  

A=pi x r2

solve r = (A / PI )^0.5                                 R = 1.15               Diam = 2.30 
                                                                R = 29.19 sq mm   Diam = 58.39 sq mm 

**(Note: I plan to introduce two vertical slots to introduce primary air in the tunnel from the firebox to the heat riser.  The plan is to warm this air prior to introducing it to the firebox.  It seems reasonable to me that introducing this volume of air via a tube vs. a rectangular port will be easier for me to fabricate. This is why I solve for 'r' radius to get the area required.)

[coisinger]

Ok, I created a dropbox account and here's the link to the excel spreadsheet. Enjoy!

www.dropbox.com/s/hoqklomz1g831yd/Batch%20Box.xlsx?dl=0

[fzurzolo]

Thanks Coisinger,

I was gonna make this for myself . . . and now I don't have to .  You da man!

[SteveStuff]

Thanks!

[satamax]

Duh, isn't it the same as this one?

donkey32.proboards.com/attachment/download/1146

That you can find here

donkey32.proboards.com/thread/734/peterberg-batch-box-dimensions?page=1

[coisinger]

Yes and no.

I needed to be able to a bit more flexibility in how some of the values where calculated (Port calculation: Allows for alternative sizing based on the calculated area, Primary Air - Again, user input for size based on area, Secondary Air - user input for size based on Area) as well as the calculation for round ports for Primary and Secondary air (Port Dimension as well in the future) based on area. I also plan on using a separate tab to calculate based on "B" that will calculate the other values. Just some flexibility and clarification for my understanding and future application that I thought might be helpful.

Maybe yes it's redundant, if so and not deemed useful, it can be removed.

For my purposes, I plan on building with firebrick.  Dimensions are standard, so you can adjust the values to get a "modular sized" outcome that still fits in the known parameters for a batch box rocket.

[satamax]

Coisinger, if you think it's useful, why would anybody remove it?

Tolerances in dimensions, for me, i shoot for 5/10%, and that's Boris!