CRJ200 Captain experienced a flaps fail caution message during approach in icing conditions with the flaps zero. The crew diverted to a longer runway where the Captain executes a no flap approach in icing conditions; with spoilers fully extended to accommodate the high thrust required for successful wing anti-ice operation.

Narrative

On arrival descent; upon selecting flaps from 0 to 8 [we] received 'FLAPS FAIL' caution message. Flaps indicted 0 degrees. [We] entered holding to run [through the] QRH. While conferring with [the] Dispatcher we decided to divert for a longer runway. Arrived without incident; declared emergency; and executed a flap zero approach and landing successfully. The icing conditions required the use of flight spoilers fully deployed during the ILS approach in order to maintain approach speed and provide adequate bleed air for the wing anti-icing equipment. Result was an unusually nose high attitude. This was the second 'flaps fail at zero' event for this aircraft in two days. After arrival; Dispatch inquired as to whether I was comfortable going ahead and flying this aircraft to the original destination with passengers following our circuit breaker reset procedure. I responded that since the exact same icing conditions which probably contributed to/caused the flap issue continued to exist there; as well as most points in the vicinity; and that this was the second time in two days that this had happened with this aircraft; that I would respectfully decline their invitation. This was affirmed by [the] Chief Pilot. We later repositioned the aircraft in VMC conditions where a crew was waiting to take it on a revenue flight.The [cause is] inadequate design of the flap system on the CRJ200. This system is very susceptible to frozen precipitation. In my humble opinion; it appears that an engineering solution is required for this issue versus the continued band aid modification of procedures for the operation of the aircraft.