Experimental Mechanics

, Volume 16, Issue 9, pp 349–355 | Cite as

Shock-front loading method for studies in dynamic photoelasticity

Paper outlines a versatile method of applying a well-defined dynamic load to models for photoelastic stress studies
  • A. W. Miles


A versatile technique for applying a well-defined dynamic load to models for studies in dynamic photoelasticity is described. The method utilizes the shock front produced in a gas-dynamic shock tube to apply a load to models by direct normal impact. The principles and scope of the method are described and some examples of the dynamic stresses arising from shock-front impact on a low-modulus photoelastic model are presented and discussed. The method is suited to studies where simple variation and accurate determination of the load-cycle parameters, as well as precise reproducibility, are necessary. The method, in addition, permits close-field study of the initial response of materials to dynamic loading to be undertaken.


Mechanical Engineer Fluid Dynamics Dynamic Load Shock Front Accurate Determination 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



shock-wave speed (m/s)


absolute pressure (kPa)


P i /P j where subscriptsi orj aren


1—refers to undisturbed region ahead of shock front


2—refers to region behind incident-shock front


5—refers to region behind reflected-shock front


(P 5 −P 1 )—reflected-shock pressure sensed by model (kPa)


velocity of incident-shock front (m/s)

γ=α+1/α−1 where α

ratio of specific heats (Cp/Cv) 1, 4 for air


density (kg/m3)


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Copyright information

© Society for Experimental Mechanics, Inc. 1976

Authors and Affiliations

  • A. W. Miles
    • 1
  1. 1.Department of Mechanical EngineeringUniversity of Cape TownRondebosch, Cape ProvinceSouth Africa

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