Fluid Dynamics

Introduction

This memorandum reports on the results of the comparison of the Williams and an industry leading golf driver. It also contains flow visualizations comparing the performance of the clubs. The simulations were conducted in freestream at a speed of 118mph.

Drag Results

graph

The Williams driver produces 19% less drag force than the industry leading golf driver which results in a 11.5% decrease in drag coefficient.

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oil

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comparison

The Williams driver shows a much smaller wake (size of the blue shaded area off the top of the club head), this can be attributed to the trip on the top of the club as well as the diffuser underneath the club.

The Williams driver shows better pressure recovery behind the club, evident by the lighter shade of blue.

The circled area on the Williams shows the flow through the diffuser helping in this pressure recovery (Circled Area).

 

comparison

 

The Williams wake is narrower than industry leading driver's wake, this can be attributed to the wings along the side of the club helping keep the flow attached.

The white area in the center of the wake supports what was seen in the previous slide, flow through the diffuser is aiding in the pressure recovery resulting in lower drag.

The small area of white on the sides of the wake which indicate the wings help to keep the air attached.

comparison

These images show where drag is being produced on the top of the club. The darker areas of blue indicate higher levels of drag production.

Industry leading driver has a larger area of drag production on the top of the club.

The area on other industry leading driver is darker blue, i.e. more intense drag production.

The lower drag on the Williams can be attributed to the trip helping to stabilize the flow.

 

comparison

 

The flow moving around the side and over the top of the Williams club is more stable and better managed than that of other industry leading driver.

This is accomplished by the inclusion of the wings and the trip on the Williams.

 

drag accumulation

 

The face design of the Williams shows a .1 lb. decrease over the industry leading driver.

The slope of the drag accumulation is less on the Williams. This could be attributed to the stabilization of the flow due to the trip.

 

Summary:

 

The Williams driver showed less drag in both force and coefficient than the industry leading driver.

The trip on the top of the Williams driver helped to stabilize the flow over the top of the club, resulting in a smaller wake.

The diffuser helped in the pressure recovery of the flow, contributing to the lower drag.

The wings helped to keep flow attached around the sides of the driver.

 


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