Database

db={"coll":[{"_id":ObjectId("5524d12d2702a21830bdb8e5"),"code":"Apple","name":"iPhone","parameters":[{"code":"xxx","name":"Andrew","value":"9"},{"code":"yyy","name":"Joy","value":"7"}]}]}

Query

db.coll.update({"parameters.name":"Andrew"},[{"$set":{"parameters":{"$concatArrays":["$parameters",[{"code":{"$arrayElemAt":["$parameters.code",{"$indexOfArray":["$parameters.name","Andrew"]}]},"name":"bar","value":"10"}]]}}}],{multi:true})

Result