You can follow the ASTM C186 guidelines for determination of heat of hydration of hydraulic cement using Calorimeter.

the best method is by using

1- ASTM C1702 - 17

Standard Test Method for Measurement of Heat of Hydration of Hydraulic Cementitious Materials Using Isothermal Conduction Calorimetry.

2-you can used thermo couple and its reader which expensive.

3-or the simplest and the fastest way is by using thermometers

Many thanks Surender Singh , and Dr.Ola for your comments.

Regards

Dear Doha M Al Saffar, kindly see the article " Measurement of the heat of hydration of cement " by P.Livesey, A.Donnelly and C.Tomlinson

Many thanks dear Dr. Mohannad,

I've looked at your suggestion article before a few days.

Regards