PSModel a look inside

HOME

Introduction

Quick Start

Quick Series
Facts

PSModel
Program

Data Input

Data Output

Importing a
Data file into
MS Excel

Main Menu

Main Screen

Printing
Graphs
and Data

Screen Colors
and Fonts

Screen
Graphs

Shortcuts

Working
with Data

Testing:

Test Sheet

Examples

19' Ski Boat

34' Sailboat

41' Utility Boat

Technical

Blade Area
Ratio

Calculating
the Cavitation
Number

Horsepower
Losses

Hull Speed

Kt Breakdown

Propeller
Geometry

Propeller Law

Wake Factors

Glossary

References

Quick Start:

To get started quickly follow these steps:

STEP 1: Open a Series Dialog Box by clicking Series on the Main Menu and then clicking on one of the following Propeller Series:

1) B Series (B) --  a noncavitating Series used to evaluate propeller performance on low speed vessels including yachts, recreational boats, and ships.  This Series has a unique geometry but can be used to approximate performance of many commercially available propellers including 2 and 3 blade propellers commonly used on sailboats.

2) Gawn Burrill Atmospheric Series (GBA) -- a digitized 3 blade, subcavitating Series used for higher speed boats with flat faced, commercial propellers with minimal cavitation, i.e., high speed lightly loaded propellers.  Data for this Series was digitized from Gawn Burrill diagrams.

3) Gawn Burrill Cavitating Series (GBD) -- a digitized 3 blade, cavitating Series used by many to approximate performance of flat faced, commercial propellers typically found on small high speed vessels including recreational boats.  Data for this Series was digitized from Gawn Burrill diagrams.

4) Navy 3 Bladed Series (NV3) -- Cavitating Series that consist of commercial, flat faced, 3 bladed propellers typically found on small commercial vessels, yachts, and recreational boats. Blade Area Ratio (BAR) is limited to 0.54.  This Series was tested by the Navy using 2 ft. diameter propellers on an instrumented boat under actual sea conditions. 

5) Navy 4 Bladed Series (NV4) --  Cavitating Series that consist of flat faced, 4 bladed propellers similar to those found on small commercial vessels, yachts, and recreational boats.  Blade Area Ratio (BAR) is limited to 0.70.  This Series was tested by the Navy using 2 ft. diameter propellers on an instrumented boat under actual sea conditions.

6) Newton Rader Series (NR) -- Cavitating, 3 bladed Series based on a unique propeller geometry for use on high speed craft.  Performance predictions based on this Series should be used only for propellers with the Newton Rader geometry.

7) Segmental Sections Series (GBL) -- a polynomial representation of 3 and 4 bladed, commercial, flat faced propellers typically found on slower recreational boats, yachts, and commercial vessels.

8) Gawn Burrill Atmospheric Series (GRJ) -- a polynomial representation of the subcavitating portion of the 3 bladed Gawn Burrill Series, see GBA above.  This Series can be used for higher speed boats with flat faced, commercial propellers with minimal cavitation, i.e., high speed lightly loaded propellers.  The P/D range for this Series is slightly less than that of GBA.

9) Gawn Burrill Cavitating Series (GBR) -- a polynomial representation of the cavitating portion of the 3 bladed Gawn Burrill Series.  The maximum cavitation number is 2.0.  Polynomial representation minimizes nonlinearities that can arise with linear interpolation used by GBD above.  The P/D range for this Series is slightly less than that of GBD.  This Series can be used to approximate performance of flat faced, commercial propellers typically found on small high speed vessels with heavily loaded propellers, including recreational boats.

More information on the above Propeller Series can be found under Quick Series Facts.

STEP 2: Select Tools \ Density Table from the Main Menu and select Salt Water or Fresh Water.  If known, enter the water temperature; if not, enter 59 degrees.

STEP 3:  If you are entering boat speed and engine RPM click on the MPH/RPM checkbox in the Series Dialog Box.  Otherwise, click on the Adv. Coef. J checkbox.

STEP 4:  Change any information that needs to be changed in the Series Dialog Box, and click the Calculate Button or press the Return Key.

1) The calculated J vs. Kt, Kq, and Efficiency curves are graphed in the Graph Window on the Main Screen for the propeller parameters entered in the Series Dialog Box.

2) Calculation results are shown in the Data Window on the lower half of the Main Screen.  Calculated values of Kt, Kq, and Efficiency are shown for the Advance Coefficient, J.   If boat speed and RPM were entered into the Series Dialog Box then torque and horsepower absorbed by the propeller, as well as J, will be calculated.  Calculated torque and horsepower do not included losses due to bearings or a reduction gear.

STEP 5:  After several rows of data are in the Data Window, select Tools \ Graph Cols... from the main menu.  A dialog box opens allowing data in columns to be graphed on the screen.  This is helpful, for example, if boat speed values have been entered and you would like to see propeller torque graphed against boat speed or horsepower.

STEP 6:  Click File \ Save As... on the main menu to save the data just created to a file.