pubmed-article:3405139 | pubmed:abstractText | The heat diffusion equation for a water calorimeter under isothermal and adiabatic boundary conditions has been solved analytically for a general source function. Based upon this model an interactive computer program has been developed and employed to predict the temporal variation of the temperature distribution in a water calorimeter irradiated with 250 kV, 4-, 6-, and 25-MV x rays and 7-, 13-, and 32-MeV electrons. The model requires central-axis depth dose curves as inputs and allows for any number of alternate heating and cooling periods. It is found that the shape of the cooling curve following an irradiation period depends upon the location of the point of measurement, the choice of boundary conditions, and the thermal history of the calorimeter. | lld:pubmed |