Flow path resistor and heat exchanger

A flow path resistor comprising:

• an outer frame member configured to partition
• a fluid introduction port formed at one end of the outer frame member, the fluid introduction port being configured to introduce fluid,
• a fluid lead-out port formed at another end of the outer frame member, the fluid lead-out port being configured to draw out the fluid, and
• a hollow portion configured to communicate the fluid introduction port and the lead-out port,
• the outer frame member extending in one direction;
• and
• a plurality of resistance-imparting portions disposed inward of an outer surface of the outer frame member, the plurality of resistance-imparting portions including a first contraction flow portion configured to contract flow of the fluid, and an enlarged diameter portion disposed in the hollow portion and being configured to communicate with the first contraction flow portion,
• wherein the plurality of resistance-imparting portions are disposed adjacent to each other,
• of the plurality of resistance-imparting portions adjacent to each other, the first contraction flow portion forming one of the plurality of resistance-imparting portions is in communication with the enlarged diameter portion forming another one of the plurality of resistance-imparting portions, and
• a plurality the first contraction flow portions forming the plurality of resistance-imparting portions adjacent to each other are disposed at different positions in a direction in which the outer frame member extends.