How to pass multiple input parameters to Process Model exposed as webservice in

Are you asking about passing multiple values or a value of type multiple?
Former should be straight-forward - as the WSDL would provide you with the info. Latter, if you are using API based invocation, then any list will be translated into multiple value. If you're using XML (like SOAPUI), then you need to pass multiple values
e.g.
<myParameter>
<value>A</value>
<value>B</value>
</myParameter>

Are you asking about passing multiple values or a value of type multiple?
Former should be straight-forward - as the WSDL would provide you with the info. Latter, if you are using API based invocation, then any list will be translated into multiple value. If you're using XML (like SOAPUI), then you need to pass multiple values
e.g.
<myParameter>
<value>A</value>
<value>B</value>
</myParameter>