How to set up a network connection between Android phone and Windows PC without Internet
If you are using Windows 7 try this,


Create an ad-hoc network in your PC (This would help you Create WiFi Network)
Connect your Android device to the WiFi network you created in past step
Open the browser in your phone and type PCs IP address/your web app name (I hope you run your web app on some servers like Apache Tomcat/WAMP ..)