Why did americans accept the constitution, with its strong national government and powerful executive, after, only a decade earlier, violently revolting against similar british institutions?

"revolting against similar British Institutions" - actually no. British institutions were the state (colonial) legislatures and governors: there was no national government of America before Independence. Each colony was independent, except for very weak oversight from London - oversight so weak that the UK govt couldn't even enforce the very low taxes it tried to impose.

Also, the US had tried weak central govt in between 1776 and 1789, and it was a hopeless failure. Furthermore, US constitution doesn't impose a strong national government - it's a rather weak national government compared, for example, to the govts of the UK and France at the time (and even now). Over time, however, the power of the central govt has grown in response to the needs of the nation.