The phrase "almost equal size" is correct and usable in written English.
It can be used when describing two or more objects that are similar in dimensions but not exactly the same.
Example: "The two boxes were of almost equal size, making them easy to stack on top of each other."
Alternatives: "nearly the same size" or "approximately equal in size."
Transient and steady fluidization experiments of binary mixtures with almost equal size but different densities were conducted.
A 575-square-foot master bedroom has a bathroom of almost equal size, and ceilings in the guest bathrooms are painted the same color as their respective bedrooms.
But up to the age of about 50, the generations are of almost equal size and the shape has near-vertical sides.
Depending on the PMMA fraction, wCCMs with a mixed corona, spherical PMMA patches embedded in a continuous PS corona, as well as alternating PS and PMMA patches of almost equal size can be realized.
Some rode bikes, typical of the 1880's and 1890's, with one very large wheel and one small wheel, while others rode bikes of Lallement's original design, with two wheels of almost equal size but with the pedals attached directly to the front wheel.
The households were divided into six control groups of almost equal size.
It also comprises large, almost equal sized Muslim and Christian communities.
At the same time, the PS substrates resulted in the almost equal sizes and densities of Cu NPs.
ADMSC effectively partitions PPI networks into biologically significant clusters with almost equal sizes, while being very fast, robust and appealing simple.
For each species, three boundaries were chosen to divide the entire set of linked duplog pairs from each species into four subsets of almost equal sizes.
Note that, in the event-based analyses, the three boundaries for the physical distance were chosen to divide the entire set of linked duplication events into four subsets of almost equal sizes.
